Deinonychosauria

@techreport{ostrom1969osteology2,
    author = "Ostrom, J. H",
    title = "Osteology of Deinonychus antirrhopus, an unusual theropod dinosaur from the Lower Cretaceous of Montana",
    year = "1969",
    howpublished = "Bulletin of the Peabody Museum of Natural History, v. 30, p. 1-165",
    note = "talkorigins\_source = {true}; raw\_reference = {Ostrom, J. H., 1969, Osteology of Deinonychus antirrhopus, an unusual theropod dinosaur from the Lower Cretaceous of Montana: Bulletin of the Peabody Museum of Natural History, v. 30, p. 1-165.}"
}

@article{russell1969a4,
    author = "Russell, D. A",
    title = "A new specimen of Stenonychosaurus from the Oldman Formation (Cretaceous) of Alberta",
    year = "1969",
    journal = "Canadian Journal of Earth Sciences, v. 6, p. 595-612",
    note = "talkorigins\_source = {true}; raw\_reference = {Russell, D. A., 1969, A new specimen of Stenonychosaurus from the Oldman Formation (Cretaceous) of Alberta: Canadian Journal of Earth Sciences, v. 6, p. 595-612.}"
}

@misc{ostrom1976on3,
    author = "Ostrom, J. H",
    title = "On a new specimen of the Lower Cretaceous theropod dinosaur Deinonychus antirrhopus",
    year = "1976",
    howpublished = "Breviora, v. 439, p. 1-21",
    note = "talkorigins\_source = {true}; raw\_reference = {Ostrom, J. H., 1976, On a new specimen of the Lower Cretaceous theropod dinosaur Deinonychus antirrhopus: Breviora, v. 439, p. 1-21.}"
}

@misc{sues1977the6,
    author = "Sues, H.-D",
    title = "The skull of Velociraptor mongoliensis, a small theropod from Mongolia",
    year = "1977",
    howpublished = "Palontologische Zeitschrift, v. 51, p. 173-184",
    note = "talkorigins\_source = {true}; raw\_reference = {Sues, H.-D., 1977, The skull of Velociraptor mongoliensis, a small theropod from Mongolia: Palontologische Zeitschrift, v. 51, p. 173-184.}"
}

@misc{osmolska1982hulsanpes1,
    author = "Osmolska, H",
    title = "Hulsanpes perlei n.g. n.sp. (Deinonychosauria, Saurischia, Dinosauria) from the Upper Cretaceous Barun Goyot Formation of Mongolia",
    year = "1982",
    howpublished = "Neues Jb. Geol. Palaeont. Mh., p. 440-448",
    note = "talkorigins\_source = {true}; raw\_reference = {Osmolska, H., 1982, Hulsanpes perlei n.g. n.sp. (Deinonychosauria, Saurischia, Dinosauria) from the Upper Cretaceous Barun Goyot Formation of Mongolia: Neues Jb. Geol. Palaeont. Mh., p. 440-448.}"
}

@misc{russell1982reconstruction5,
    author = "Russell, D. A. and Sequin, R",
    title = "Reconstruction of the small Cretaceous theropod Stenonychosaurus inequalis and a hypothetical dinosauroid",
    year = "1982",
    howpublished = "Syllogeous, v. 37, p. 1-43",
    note = "talkorigins\_source = {true}; raw\_reference = {Russell, D. A., and Sequin, R., 1982, Reconstruction of the small Cretaceous theropod Stenonychosaurus inequalis and a hypothetical dinosauroid: Syllogeous, v. 37, p. 1-43.}"
}

ABSTRACT The Berriasian Rupelo Formation of the W Cameros Basin consists of a 2–200 m thickness of marginal and open lacustrine carbonate and associated deposits. Open lacustrine facies contain a non‐marine biota with abundant charophytes (both stems and gyrogonites), ostracods, gastropods and rare vertebrates. Carbonate production was mainly biogenic. The associated marginal lacustrine (‘palustrine’) facies show strong indications of subaerial exposure and exhibit a wide variety of pedogenic fabrics. Silicified evaporites found near to the top of the sequence reflect a short hypersaline phase in the lake history. The succession was laid down in a low gradient, shallow lake complex characterized by wide fluctuations of the shoreline. Carbon and oxygen stable isotope analyses from the carbonates show non‐marine values with ranges of δ 13 from − 7 to − 11‰and δ 18 from − 3 to − 7.5‰. Differences in the isotopic composition of open lacustrine carbonates are consistent with sedimentary evidence of variation in organic productivity within the lake. Analyses from the entire sample suite plot on a linear trend; isotopic compositions become lighter with increasing evidence of pedogenic modification. This suggests progressive vadose zone diagenesis and influence of meteoric waters rich in soil‐derived CO 2. The stable isotope data thus support evidence from petrography and facies relations that ‘palustrine’limestones form through pedogenic modification of lake carbonates.

@article{doi101111j136530911989tb02092x,
    author = "Platt, Nigel H.",
    title = "Lacustrine carbonates and pedogenesis: sedimentology and origin of palustrine deposits from the Early Cretaceous Rupelo Formation, W Cameros Basin, N Spain",
    year = "1989",
    journal = "Sedimentology",
    abstract = "ABSTRACT The Berriasian Rupelo Formation of the W Cameros Basin consists of a 2–200 m thickness of marginal and open lacustrine carbonate and associated deposits. Open lacustrine facies contain a non‐marine biota with abundant charophytes (both stems and gyrogonites), ostracods, gastropods and rare vertebrates. Carbonate production was mainly biogenic. The associated marginal lacustrine (‘palustrine’) facies show strong indications of subaerial exposure and exhibit a wide variety of pedogenic fabrics. Silicified evaporites found near to the top of the sequence reflect a short hypersaline phase in the lake history. The succession was laid down in a low gradient, shallow lake complex characterized by wide fluctuations of the shoreline. Carbon and oxygen stable isotope analyses from the carbonates show non‐marine values with ranges of δ 13 from − 7 to − 11‰and δ 18 from − 3 to − 7.5‰. Differences in the isotopic composition of open lacustrine carbonates are consistent with sedimentary evidence of variation in organic productivity within the lake. Analyses from the entire sample suite plot on a linear trend; isotopic compositions become lighter with increasing evidence of pedogenic modification. This suggests progressive vadose zone diagenesis and influence of meteoric waters rich in soil‐derived CO 2. The stable isotope data thus support evidence from petrography and facies relations that ‘palustrine’limestones form through pedogenic modification of lake carbonates.",
    url = "https://doi.org/10.1111/j.1365-3091.1989.tb02092.x",
    doi = "10.1111/j.1365-3091.1989.tb02092.x",
    openalex = "W2010268246",
    references = "doi1010160037073873900092, doi101111j136530911988tb00992x"
}

@article{doi101017cbo9780511608377011,
    author = "Currie, P. and Rigby, J. and Sloan, R. E.",
    title = "Dinosaur Systematics: Theropod teeth from the Judith River Formation of southern Alberta, Canada",
    year = "1990",
    booktitle = "Dinosaur Systematics",
    url = "https://www.semanticscholar.org/paper/fedead3cc1ae0ec35f3954946391d9906ed25ae7",
    doi = "10.1017/CBO9780511608377.011",
    is_oa = "true",
    pages = "107-126",
    semanticscholar_citation_count = "246",
    semanticscholar_id = "fedead3cc1ae0ec35f3954946391d9906ed25ae7"
}

An articulated skeleton of a 1 m long theropod from Early Cretaceous strata in Inner Mongolia is clearly referrable to the Troodontidae, representing the most complete specimen known of this group of small carnivorous dinosaurs. The tail and neck of the animal were curled next to its body upon burial; the upper surface of the skeleton was badly damaged by erosion. Previously unknown details of troodont morphology include a quadratic contact with the braincase wall (forming part of a channel leading to the lateral depression), a presacral vertebral count possibly similar to that of most theropods, absence of ossified caudal tendons, presence of a rod-like clavicle, and absence of sternal ossifications. A new genus and species (Sinornithoides youngi n.gen., n.sp.) is established for the specimen on the basis of its short skull, laterally directed orbital rim of the frontal, and elongated hind limb. A reassessment of character distributions in other small theropods and primitive birds must be completed before troodontid affinities can be established with greater precision.

@article{doi101139e93187,
    author = "Russell, Dale A. and Dong, Zhi-Ming",
    title = "A nearly complete skeleton of a new troodontid dinosaur from the Early Cretaceous of the Ordos Basin, Inner Mongolia, People's Republic of China",
    year = "1993",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "An articulated skeleton of a 1 m long theropod from Early Cretaceous strata in Inner Mongolia is clearly referrable to the Troodontidae, representing the most complete specimen known of this group of small carnivorous dinosaurs. The tail and neck of the animal were curled next to its body upon burial; the upper surface of the skeleton was badly damaged by erosion. Previously unknown details of troodont morphology include a quadratic contact with the braincase wall (forming part of a channel leading to the lateral depression), a presacral vertebral count possibly similar to that of most theropods, absence of ossified caudal tendons, presence of a rod-like clavicle, and absence of sternal ossifications. A new genus and species (Sinornithoides youngi n.gen., n.sp.) is established for the specimen on the basis of its short skull, laterally directed orbital rim of the frontal, and elongated hind limb. A reassessment of character distributions in other small theropods and primitive birds must be completed before troodontid affinities can be established with greater precision.",
    url = "https://doi.org/10.1139/e93-187",
    doi = "10.1139/e93-187",
    openalex = "W2005056616"
}

A new, well-preserved specimen of Troodon formosus is the first to reveal the internal anatomy of the lower part of the braincase. In addition to providing new information on the brain of this highly encephalized dinosaur, the uncrushed bones clear up anatomical details left obscure by earlier studies. Computerized tomography (CT) scans reveal the nature of the inner ear and the course of the pneumatic ducts diverging from the middle ear. Evidence is presented to show that four of the five periotic pneumatic systems found in bird skulls are present in Troodon. The anterior tympanic recess is the most elaborate system, and diverticula from each side extend anteriorly, dorsally and, posteriorly from the middle ear. The posterior tympanic recess is located within the paroccipital process and the basioccipital, but the pneumatopore posterolateral to the stapedial recess is secondarily closed. The dorsal periotic sinus is represented by a smooth-surfaced concavity on the lateral surface of the prootic. The position of a pneumatic recess in this region is demonstrated by the presence of a pneumatopore in the quadrate. Diverticula from the anterior and posterior tympanic recesses are connected within braincase bones, and a possible pneumatopore in the prootic may connect these to the dorsal tympanic recess. The pneumatic condition of the troodontid articular is unknown. Contralateral connections of the sinus systems have been used to argue for a close relationship between birds and crocodiles, but their presence in this specimen suggests that they appeared more than once in archosaurs or that they are plesiomorphic for crocodiles, dinosaurs, and birds. Cranial pneumaticity cannot be used by itself to resolve the interrelationships of crocodiles, theropods, and birds, but other characters suggest derivation of birds from theropods.

@article{doi101139e93194,
    author = "Currie, Philip J. and Zhao, Xi-Jin",
    title = "A new troodontid (Dinosauria, Theropoda) braincase from the Dinosaur Park Formation (Campanian) of Alberta",
    year = "1993",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "A new, well-preserved specimen of Troodon formosus is the first to reveal the internal anatomy of the lower part of the braincase. In addition to providing new information on the brain of this highly encephalized dinosaur, the uncrushed bones clear up anatomical details left obscure by earlier studies. Computerized tomography (CT) scans reveal the nature of the inner ear and the course of the pneumatic ducts diverging from the middle ear. Evidence is presented to show that four of the five periotic pneumatic systems found in bird skulls are present in Troodon. The anterior tympanic recess is the most elaborate system, and diverticula from each side extend anteriorly, dorsally and, posteriorly from the middle ear. The posterior tympanic recess is located within the paroccipital process and the basioccipital, but the pneumatopore posterolateral to the stapedial recess is secondarily closed. The dorsal periotic sinus is represented by a smooth-surfaced concavity on the lateral surface of the prootic. The position of a pneumatic recess in this region is demonstrated by the presence of a pneumatopore in the quadrate. Diverticula from the anterior and posterior tympanic recesses are connected within braincase bones, and a possible pneumatopore in the prootic may connect these to the dorsal tympanic recess. The pneumatic condition of the troodontid articular is unknown. Contralateral connections of the sinus systems have been used to argue for a close relationship between birds and crocodiles, but their presence in this specimen suggests that they appeared more than once in archosaurs or that they are plesiomorphic for crocodiles, dinosaurs, and birds. Cranial pneumaticity cannot be used by itself to resolve the interrelationships of crocodiles, theropods, and birds, but other characters suggest derivation of birds from theropods.",
    url = "https://doi.org/10.1139/e93-194",
    doi = "10.1139/e93-194",
    openalex = "W2022558394"
}

Tyrannosaurids are a well-supported clade of very large predatory dinosaurs of Late Cretaceous Asiamerica. Traditional dinosaurian systematics place these animals within the infraorder Carnosauria with the other large theropods (allosaurids, megalosaurids). A new cladistic analysis indicates that the tyrannosaurs were in fact derived members of the Coelurosauria, a group of otherwise small theropods. Despite certain gross cranial similarities with the large predators of the Jurassic and Early Cretaceous, the Late Cretaceous tyrannosaurids are shown to be the sister group to ornithomimids and troodontids, which share a derived condition of the metatarsus. This clade is found to be nested within Maniraptora, which is a more inclusive taxon than previously recognized. The atrophied carpal structure found in tyrannosaurids and ornithomimids is derived from a maniraptoran condition with a large semilunate carpal, rather than from the plesiomorphic theropod morphology. The taxa “Carnosauria” and “Deinonychosauria” (Dromaeosauridae plus Troodontidae) are shown to be polyphyletic, and the Late Jurassic African form Elaphrosaurus is found to be the sister taxon to Abelisauridae rather than a primitive ornithomimosaur. Purported allosaurid-tyrannosaurid synapomorphies are seen to be largely size-related, present in the larger members of both clades, but absent in smaller members of the Tyrannosauridae. The remaining giant tetanurine theropods (Megalosaurus and Torvosaurus) were found to be progressively distant outgroups to an allosaurid-coelurosaur clade. The inclusion of the Tyrannosauridae within Maniraptora suggests a major adaptive radiation of coelurosaurs within Cretaceous Asiamerica comparable to contemporaneous radiations in various herbivorous dinosaurian clades.

@article{doi101017s0022336000026706,
    author = "Holtz, Thomas R.",
    title = "The phylogenetic position of the Tyrannosauridae: implications for theropod systematics",
    year = "1994",
    journal = "Journal of Paleontology",
    abstract = "Tyrannosaurids are a well-supported clade of very large predatory dinosaurs of Late Cretaceous Asiamerica. Traditional dinosaurian systematics place these animals within the infraorder Carnosauria with the other large theropods (allosaurids, megalosaurids). A new cladistic analysis indicates that the tyrannosaurs were in fact derived members of the Coelurosauria, a group of otherwise small theropods. Despite certain gross cranial similarities with the large predators of the Jurassic and Early Cretaceous, the Late Cretaceous tyrannosaurids are shown to be the sister group to ornithomimids and troodontids, which share a derived condition of the metatarsus. This clade is found to be nested within Maniraptora, which is a more inclusive taxon than previously recognized. The atrophied carpal structure found in tyrannosaurids and ornithomimids is derived from a maniraptoran condition with a large semilunate carpal, rather than from the plesiomorphic theropod morphology. The taxa “Carnosauria” and “Deinonychosauria” (Dromaeosauridae plus Troodontidae) are shown to be polyphyletic, and the Late Jurassic African form Elaphrosaurus is found to be the sister taxon to Abelisauridae rather than a primitive ornithomimosaur. Purported allosaurid-tyrannosaurid synapomorphies are seen to be largely size-related, present in the larger members of both clades, but absent in smaller members of the Tyrannosauridae. The remaining giant tetanurine theropods (Megalosaurus and Torvosaurus) were found to be progressively distant outgroups to an allosaurid-coelurosaur clade. The inclusion of the Tyrannosauridae within Maniraptora suggests a major adaptive radiation of coelurosaurs within Cretaceous Asiamerica comparable to contemporaneous radiations in various herbivorous dinosaurian clades.",
    url = "https://doi.org/10.1017/s0022336000026706",
    doi = "10.1017/s0022336000026706",
    openalex = "W1852998243",
    references = "crossref1976allosaurus, doi101016s0016699588800664, doi101017s247526300000091x, doi10108002724634199110011426, doi101111j109583121976tb00244x, doi1015468yhxmzl, doi1023072992353, doi1023073514548, doi102475ajss3179786, doi102475ajss319111253, doi1034191b109, doi105281zenodo16171435, openalexw3215057009, openalexw607142922, smith1990osteology, talbot1911podokesaurus, welles1954new, wilson1985stenonychosaurus"
}

Jurassic fossil vertebrates collected from the Falla Formation in the Central Transantarctic Mountains included a partial skull and postcranial elements of a crested theropod, Cryolophosaurus ellioti gen. nov. sp. nov. The theropod bears some resemblance to the large tetanurans of the Middle to Late Jurassic but also has primitive ceratosaurian features. Elements from a prosauropod, teeth from scavenging theropods, a pterosaur humerus, and a tritylodont molar were also recovered. The presence of this fauna suggests that a mild climate existed at high paleolatitude in this area of Gondwana during the Early Jurassic.

@article{doi101126science2645160828,
    author = "Hammer, William R. and Hickerson, William J.",
    title = "A Crested Theropod Dinosaur from Antarctica",
    year = "1994",
    journal = "Science",
    abstract = "Jurassic fossil vertebrates collected from the Falla Formation in the Central Transantarctic Mountains included a partial skull and postcranial elements of a crested theropod, Cryolophosaurus ellioti gen. nov. sp. nov. The theropod bears some resemblance to the large tetanurans of the Middle to Late Jurassic but also has primitive ceratosaurian features. Elements from a prosauropod, teeth from scavenging theropods, a pterosaur humerus, and a tritylodont molar were also recovered. The presence of this fauna suggests that a mild climate existed at high paleolatitude in this area of Gondwana during the Early Jurassic.",
    url = "https://doi.org/10.1126/science.264.5160.828",
    doi = "10.1126/science.264.5160.828",
    openalex = "W1978523294",
    references = "brouwers1987dinosaurs, doi1010160012821x94900299, doi1010160166516289900682, doi101017s0954102091000391, doi101029ar036, doi101126science20544131377, doi1011300016760619921040543pcdtej23co2, doi101360yb1984279970"
}

A major question in Mesozoic biogeography is how the land-based dinosaurian radiation responded to fragmentation of Pangaea. A rich fossil record has been uncovered on northern continents that spans the Cretaceous, when continental isolation reached its peak. In contrast, dinosaur remains on southern continents are scarce. The discovery of dinosaurian skeletons from Lower Cretaceous beds in the southern Sahara shows that several lineages of tetanuran theropods and broad-toothed sauropods had a cosmopolitan distribution across Pangaea before the onset of continental fragmentation. The distinct dinosaurian faunas of Africa, South America, and Asiamerica arose during the Cretaceous by differential survival of once widespread lineages on land masses that were becoming increasingly isolated from one another.

@article{doi101126science2665183267,
    author = "Sereno, Paul C. and Wilson, Jeffrey A. and Larsson, Hans C. E. and Dutheil, Didier B. and Sues, Hans‐Dieter",
    title = "Early Cretaceous Dinosaurs from the Sahara",
    year = "1994",
    journal = "Science",
    abstract = "A major question in Mesozoic biogeography is how the land-based dinosaurian radiation responded to fragmentation of Pangaea. A rich fossil record has been uncovered on northern continents that spans the Cretaceous, when continental isolation reached its peak. In contrast, dinosaur remains on southern continents are scarce. The discovery of dinosaurian skeletons from Lower Cretaceous beds in the southern Sahara shows that several lineages of tetanuran theropods and broad-toothed sauropods had a cosmopolitan distribution across Pangaea before the onset of continental fragmentation. The distinct dinosaurian faunas of Africa, South America, and Asiamerica arose during the Cretaceous by differential survival of once widespread lineages on land masses that were becoming increasingly isolated from one another.",
    url = "https://doi.org/10.1126/science.266.5183.267",
    doi = "10.1126/science.266.5183.267",
    openalex = "W2034114512",
    references = "doi101017s0022336000026706, doi101038361064a0, doi101086627723, doi101126science13334591105, doi101139e72031, doi101139e93179, doi1023071796560, doi105281zenodo1040385, doi105860choice331556, openalexw2603028126, openalexw2989049194"
}

Abstract Most recent studies of dinosaur phylogeny have concentrated on theropods and ornithischians. As a result, the evolutionary relationships of sauropod dinosaurs are poorly understood. In this paper previous studies of sauropod phylogeny are reviewed and contrasted with the results of a recent cladistic analysis. This analysis forms the basis for a reconstruction of sauropod phylogeny. Sauropods diverged from other dinosaurs at some time in the Upper Triassic, but a large part of their early history is totally unknown. Vulcanodonis currently the most primitive sauropod. Many, but perhaps not all, of the Jurassic Chinese sauropods form a monophyletic radiation (the Euhelopodidae) which may reflect the geographic isolation of China during the Lower Jurassic. Members of the Euhelopodidae, such as Mamenchisaurus, are not considered to be closely related to the Diplodocidae. ‘Forked’ chevrons, which have played such an important role in previous studies of sauropod phylogeny, are here considered to have evolved twice within the Sauropoda. This convergence may reflect a correlation between chevron shape and the use of the tail as a weapon within these two sauropod families. The ‘Neosauropoda’ (sister group to the Euhelopodidae) contains the Brachiosauridae, Camarasauridae and the new superfamilies Titanosauroidea and Diplodocoidea. The Cetiosauridae (here defined in a rather restricted sense) is also provisionally included within the Neosauropoda, but may be removed in future studies. The enigmatic Upper Cretaceous sauropod, Opisthocoelicaudia, is thought to be the sister taxon to the Titanosauridae and not a camarasaurid as previously suggested. The Diplodocoidea contains two well established families, the Dicraeosauridae and Diplodocidae, and the new family Nemegtosauridae. Finally, an overview of sauropod phylogeny is compared with recently published palaeogeographic reconstructions. There are many difficulties associated with the analysis of sauropod biogeographic distribution. Nevertheless, some aspects of sauropod phylogeny may be linked to the break-up of Laurasia and Gondwanaland during the Jurassic and Cretaceous.

@article{doi101098rstb19950125,
    author = "Upchurch, Paul",
    title = "The evolutionary history of sauropod dinosaurs",
    year = "1995",
    journal = "Philosophical Transactions of the Royal Society B Biological Sciences",
    abstract = "Abstract Most recent studies of dinosaur phylogeny have concentrated on theropods and ornithischians. As a result, the evolutionary relationships of sauropod dinosaurs are poorly understood. In this paper previous studies of sauropod phylogeny are reviewed and contrasted with the results of a recent cladistic analysis. This analysis forms the basis for a reconstruction of sauropod phylogeny. Sauropods diverged from other dinosaurs at some time in the Upper Triassic, but a large part of their early history is totally unknown. Vulcanodonis currently the most primitive sauropod. Many, but perhaps not all, of the Jurassic Chinese sauropods form a monophyletic radiation (the Euhelopodidae) which may reflect the geographic isolation of China during the Lower Jurassic. Members of the Euhelopodidae, such as Mamenchisaurus, are not considered to be closely related to the Diplodocidae. ‘Forked’ chevrons, which have played such an important role in previous studies of sauropod phylogeny, are here considered to have evolved twice within the Sauropoda. This convergence may reflect a correlation between chevron shape and the use of the tail as a weapon within these two sauropod families. The ‘Neosauropoda’ (sister group to the Euhelopodidae) contains the Brachiosauridae, Camarasauridae and the new superfamilies Titanosauroidea and Diplodocoidea. The Cetiosauridae (here defined in a rather restricted sense) is also provisionally included within the Neosauropoda, but may be removed in future studies. The enigmatic Upper Cretaceous sauropod, Opisthocoelicaudia, is thought to be the sister taxon to the Titanosauridae and not a camarasaurid as previously suggested. The Diplodocoidea contains two well established families, the Dicraeosauridae and Diplodocidae, and the new family Nemegtosauridae. Finally, an overview of sauropod phylogeny is compared with recently published palaeogeographic reconstructions. There are many difficulties associated with the analysis of sauropod biogeographic distribution. Nevertheless, some aspects of sauropod phylogeny may be linked to the break-up of Laurasia and Gondwanaland during the Jurassic and Cretaceous.",
    url = "https://doi.org/10.1098/rstb.1995.0125",
    doi = "10.1098/rstb.1995.0125",
    openalex = "W2026763967",
    references = "doi10102992jb00648, doi10108002724634199410011538, doi101126science2665183267, doi101139e93176, doi1023071292217, doi103989egeol8743extra625, doi105281zenodo16171435, doi105962bhlpart4439, doi105962bhltitle60562, doi105962p234849, openalexw3114518543"
}

@article{doi101127njgpm19951995397,
    author = "Frey, Eberhard and Martill, David M.",
    title = "A possible oviraptorosaurid theropod from the Santana Formation (Lower Cretaceous,?Albian) of Brazil",
    year = "1995",
    journal = "Neues Jahrbuch für Geologie und Paläontologie - Monatshefte",
    url = "https://doi.org/10.1127/njgpm/1995/1995/397",
    doi = "10.1127/njgpm/1995/1995/397",
    openalex = "W2996651501"
}

Late Cretaceous (Cenomanian) fossils discovered in the Kem Kem region of Morocco include large predatory dinosaurs that inhabited Africa as it drifted into geographic isolation. One, represented by a skull approximately 1.6 meters in length, is an advanced allosauroid referable to the African genus Carcharodontosaurus. Another, represented by a partial skeleton with slender proportions, is a new basal coelurosaur closely resembling the Egyptian genus Bahariasaurus. Comparisons with Cretaceous theropods from other continents reveal a previously unrecognized global radiation of carcharodontosaurid predators. Substantial geographic differentiation of dinosaurian faunas in response to continental drift appears to have arisen abruptly at the beginning of the Late Cretaceous.

@article{doi101126science2725264986,
    author = "Sereno, Paul C. and Dutheil, Didier B. and Iarochène, Mohamed and Larsson, Hans C. E. and Lyon, Gabrielle H. and Magwene, Paul M. and Sidor, Christian A. and Varricchio, David J. and Wilson, Jeffrey A.",
    title = "Predatory Dinosaurs from the Sahara and Late Cretaceous Faunal Differentiation",
    year = "1996",
    journal = "Science",
    abstract = "Late Cretaceous (Cenomanian) fossils discovered in the Kem Kem region of Morocco include large predatory dinosaurs that inhabited Africa as it drifted into geographic isolation. One, represented by a skull approximately 1.6 meters in length, is an advanced allosauroid referable to the African genus Carcharodontosaurus. Another, represented by a partial skeleton with slender proportions, is a new basal coelurosaur closely resembling the Egyptian genus Bahariasaurus. Comparisons with Cretaceous theropods from other continents reveal a previously unrecognized global radiation of carcharodontosaurid predators. Substantial geographic differentiation of dinosaurian faunas in response to continental drift appears to have arisen abruptly at the beginning of the Late Cretaceous.",
    url = "https://doi.org/10.1126/science.272.5264.986",
    doi = "10.1126/science.272.5264.986",
    openalex = "W2013182835",
    references = "coria1995a, doi101007bf02987808, doi101016s0016699509900389, doi101038377224a0, doi101126science2665183267, doi102113gssgfbulliv2335, doi1023072421859, doi105281zenodo1040385, doi105962p226819, openalexw1426920053, openalexw2603028126"
}

The skull of a new, and highly unusual crested dinosaur with an elongate rostrum is the first dinosaur to be named from the Santana Formation of NE Brazil. Irritator challengeri gen. et sp. nov was most likely a maniraptoran dinosaur, but its affinities to other maniraptorans remain to be established. Unique features for Irritator include the pattern of tooth replacement, a highly reduced supratemporal fenestra, extreme lateral compression of the rostrum and a saggital crest comprised of the frontal and parietal bones. Irritator was most probably a piscivore. A land link between South America and the dinosaurian faunal province of North America and Asia is indicated, probably via Africa.

@article{doi101144gsjgs15310005,
    author = "Martill, David M. and Cruickshank, A. R. I. and Frey, Eberhard and Small, Philip G. and Clarke, M.",
    title = "A new crested maniraptoran dinosaur from the Santana Formation (Lower Cretaceous) of Brazil",
    year = "1996",
    journal = "Journal of the Geological Society",
    abstract = "The skull of a new, and highly unusual crested dinosaur with an elongate rostrum is the first dinosaur to be named from the Santana Formation of NE Brazil. Irritator challengeri gen. et sp. nov was most likely a maniraptoran dinosaur, but its affinities to other maniraptorans remain to be established. Unique features for Irritator include the pattern of tooth replacement, a highly reduced supratemporal fenestra, extreme lateral compression of the rostrum and a saggital crest comprised of the frontal and parietal bones. Irritator was most probably a piscivore. A land link between South America and the dinosaurian faunal province of North America and Asia is indicated, probably via Africa.",
    url = "https://doi.org/10.1144/gsjgs.153.1.0005",
    doi = "10.1144/gsjgs.153.1.0005",
    openalex = "W2157947584",
    references = "doi101017s0022336000026706, doi10108010292389109380385, doi101126science2645160828, doi101126science2665183267, doi101127njgpm1989198979, doi101127njgpm19951995397, doi105281zenodo16171435, doi105281zenodo16246150, openalexw2788234611, openalexw3114518543"
}

@article{doi10103834356,
    author = "Chen, Peiji and Dong, Zhi-Ming and Zhen, Shuonan",
    title = "An exceptionally well-preserved theropod dinosaur from the Yixian Formation of China",
    year = "1998",
    journal = "Nature",
    url = "https://doi.org/10.1038/34356",
    doi = "10.1038/34356",
    openalex = "W1667761058",
    references = "doi101017s247526300000091x, doi101038368196a0, doi101038378349a0, doi101038385247a0, doi101139e93179, doi101139e96046, doi1015468p4gnhz, doi105281zenodo1038218, doi105281zenodo16246150, doi105860choice343307, doi105962bhltitle6856, openalexw1671792548"
}

A partial skeleton of a primitive bird, Rahona ostromi, gen. et sp. nov., has been discovered from the Late Cretaceous of Madagascar. This specimen, although exhibiting avian features such as a reversed hallux and ulnar papillae, retains characteristics that indicate a theropod ancestry, including a pubic foot and hyposphene-hypantra vertebral articulations. Rahona has a robust, hyperextendible second digit on the hind foot that terminates in a sicklelike claw, a unique characteristic of the theropod groups Troodontidae and Dromaeosauridae. A phylogenetic analysis places Rahona with Archaeopteryx, making Rahona one of the most primitive birds yet discovered.

@article{doi101126science27953581915,
    author = "Forster, Catherine A. and Sampson, Scott D. and Chiappe, Luis M. and Krause, David W.",
    title = "The Theropod Ancestry of Birds: New Evidence from the Late Cretaceous of Madagascar",
    year = "1998",
    journal = "Science",
    abstract = "A partial skeleton of a primitive bird, Rahona ostromi, gen. et sp. nov., has been discovered from the Late Cretaceous of Madagascar. This specimen, although exhibiting avian features such as a reversed hallux and ulnar papillae, retains characteristics that indicate a theropod ancestry, including a pubic foot and hyposphene-hypantra vertebral articulations. Rahona has a robust, hyperextendible second digit on the hind foot that terminates in a sicklelike claw, a unique characteristic of the theropod groups Troodontidae and Dromaeosauridae. A phylogenetic analysis places Rahona with Archaeopteryx, making Rahona one of the most primitive birds yet discovered.",
    url = "https://doi.org/10.1126/science.279.5358.1915",
    doi = "10.1126/science.279.5358.1915",
    openalex = "W2038517485",
    references = "doi101017s0022336000026706, doi101038378349a0, doi101038387390a0, doi10108002724634198710011638, doi101111j109583121976tb00244x, doi101126science2555046845, doi101126science27452901164, doi101126science2785338666, doi101126science27853411267, doi101139e93194, gregor1988the"
}

Recent discoveries of fossil vertebrates from the Late Cretaceous of Madagascar include several specimens of a large theropod dinosaur. One specimen includes a nearly complete and exquisitely preserved skull with thickened pneumatic nasals, a median frontal horn, and a dorsal projection on the parietals. The new materials are assigned to the enigmatic theropod group Abelisauridae on the basis of a number of unique features. Fossil remains attributable to abelisaurids are restricted to three Gondwanan landmasses: South America, Madagascar, and the Indian subcontinent. This distribution is consistent with a revised paleogeographic reconstruction that posits prolonged links between these landmasses (via Antarctica), perhaps until late in the Late Cretaceous.

@article{doi101126science28053661048,
    author = "Sampson, Scott D. and Witmer, Lawrence M. and Forster, Catherine A. and Krause, David W. and O’Connor, Patrick M. and Dodson, Peter and Ravoavy, Florent",
    title = "Predatory Dinosaur Remains from Madagascar: Implications for the Cretaceous Biogeography of Gondwana",
    year = "1998",
    journal = "Science",
    abstract = "Recent discoveries of fossil vertebrates from the Late Cretaceous of Madagascar include several specimens of a large theropod dinosaur. One specimen includes a nearly complete and exquisitely preserved skull with thickened pneumatic nasals, a median frontal horn, and a dorsal projection on the parietals. The new materials are assigned to the enigmatic theropod group Abelisauridae on the basis of a number of unique features. Fossil remains attributable to abelisaurids are restricted to three Gondwanan landmasses: South America, Madagascar, and the Indian subcontinent. This distribution is consistent with a revised paleogeographic reconstruction that posits prolonged links between these landmasses (via Antarctica), perhaps until late in the Late Cretaceous.",
    url = "https://doi.org/10.1126/science.280.5366.1048",
    doi = "10.1126/science.280.5366.1048",
    openalex = "W2026696841",
    references = "doi101016003101829190145h, doi101017s0022336000026706, doi10103837343, doi101038377301a0, doi101126science2665183267, doi101126science2725264986, doi101126science27953581915, doi101139e93176, doi101146annurevearth251435, doi105962p226819, openalexw648313615, sereno1997the"
}

Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous.

@article{doi101126science28253921298,
    author = "Sereno, Paul C. and Beck, Allison L. and Dutheil, Didier B. and Gado, Boubacar and Larsson, Hans C. E. and Lyon, Gabrielle H. and Marcot, Jonathan D. and Rauhut, Oliver W. M. and Sadleir, Rudyard W. and Sidor, Christian A. and Varricchio, David D. and Wilson, Gregory P. and Wilson, Jeffrey A.",
    title = "A Long-Snouted Predatory Dinosaur from Africa and the Evolution of Spinosaurids",
    year = "1998",
    journal = "Science",
    abstract = "Fossils discovered in Lower Cretaceous (Aptian) rocks in the Tenere Desert of central Niger provide new information about spinosaurids, a peculiar group of piscivorous theropod dinosaurs. The remains, which represent a new genus and species, reveal the extreme elongation and transverse compression of the spinosaurid snout. The postcranial bones include blade-shaped vertebral spines that form a low sail over the hips. Phylogenetic analysis suggests that the enlarged thumb claw and robust forelimb evolved during the Jurassic, before the elongated snout and other fish-eating adaptations in the skull. The close phylogenetic relationship between the new African spinosaurid and Baryonyx from Europe provides evidence of dispersal across the Tethys seaway during the Early Cretaceous.",
    url = "https://doi.org/10.1126/science.282.5392.1298",
    doi = "10.1126/science.282.5392.1298",
    openalex = "W2161814413",
    references = "doi101016s0195667105800199, doi101038324359a0, doi101093sysbio461195, doi101111j136531211989tb00328x, doi101126science2725264986, doi101127njgpa1991996151, doi101144gsjgs15310005, doi102113gssgfbulliv2335, doi105860choice331556, openalexw2989049194"
}

Thematic Table of Contents. Contributors. A Guide to Using the Encyclopedia. Michael Crichton, Foreword. Preface. Dedication. F.E. Novas, Abelisauridae. L.L. Jacobs, African Dinosaurs. G. Erickson, Age Determination. A. Chinsamy, Albany K. Padian and J.R. Hutchinson, Allosauroidea. P. Dodson, American Dinosaurs. L. Dingus, American Museum of Natural History. K. Carpenter, Ankylosauria. J.M. Parrish, Archosauria. J.R. Hutchinson and K. Padain, Arctometatarsalia. R.E. Molnar, Australasian Dinosaurs. L.M. Chiappe, Aves. The Editors, Avetheropoda. K. Padian, Avialae. H. Osmolska, Barun Goyot Formation. J.L. Sanz, Bastus Nesting Site. The Editors, Bavarian State Collection for Paleontology and Historical Geology. P. Currie, Bayan Mandahu. H. Osmolska, Bayn Dzak. J.R. Horner, Behavior. A. Chinsamy, Bernard Price Institute for Paleontological Research. J. Le Loeuff, Biogeography. R.M. Alexander, Biomechanics. R. Chapman, Biometrics. C. Trueman, Biomineralization. S.G. Lucas, Biostratigraphy. K. Padian, Bipedality. K. Padian, Bird Origins. B. Breithaupt, Bone Cabin Quarry. P. Currie, Braincase Anatomy. K. Padain and J.R. Hutchinson, Bullatosauria. M. Lockley, Cabo Espichel. J.S. Moratalla and J.L. Sanz, Cameros Basin Megatracksite. C. Coy, Canadian Dinosaurs. K. Carpenter, Canon City. M. Lockley, Carenque. J.S. McIntosh, Carnegie Museum of Natural History. J.R. Hutchinson and K. Padian, Carnosauria. J. Kirkland, Cedar Mountain Formation. M. Norell, Central Asiatic Expeditions. The Editors, Cerapoda. P. Dodson, Ceratopsia. T. Rowe, R. Tykoski, and J.R. Hutchinson, Ceratosauria. H. Bocherens, Chemical Composition of Dinosaur Fossils. D. Zhiming, Chinese Dinosaurs. J.M. Parrish, Chinle Formation. J.B. Smith, Cleveland-Lloyd Dinosaur Quarry. D. Maxwell, Cloverly Formation. J.R. Hutchinson and K. Padian, Coelurosauria. M.J. Ryan and A.P. Russell, Color. B. Breithaupt, Como Bluff. R.E. Chapman and D.B. Weishampel, Computers and Related Technology. J. Wright, Connecticut River Valley. D.B. Weishampel, Constructional Morphology. K. Chin, Coprolites. L.M. Witmer, Craniofacial Air Sinus Systems. E-B. Koppelhus, Cretaceous Period. J.M. Clark, Crocodylia. W.A.S. Sarjeant, Crystal Palace Dinosaurs. B. Britt and K.L. Stadtman, Dalton Wells Quarry. A. Sahni, Deccan Basalt. The Editors, Deinonychosauria. K. Carpenter, Denver Museum of Natural History. C. Coy, Devil's Coulee Dinosaur Egg Historic Site. M.J. Ryan and M.K. Vickaryous, Diet. K. Padian, Dinosauria: Definition. D. Chure, Dinosaur National Monument. A.B. Arcucci, Dinosauromorpha. C. Coy, Dinosaur Provincial Park. M. Lockley, Dinosaur Ridge. Don Lesson, Dinosaur Society. M. Lockley, Dinosaur Valley. M. Lockley, Dinoturbation. P. Dodson, Distribution and Diversity. T. Jerzykiewicz, Djadokhta Formation. P.A. Murry and R.A. Long, Dockum Group. P. Currie, Dromaeosaridae. B. Britt and B.I. Curtice, Dry Mesa Quarry. M.J. Ryan, Dryosauridae. D.A. Eberth, Edmonton Group. J.R. Horner, Egg Mountain. K.E. Mikhailov, Eggs, Eggshells, and Nests. P. Currie, Elmisauridae. The Editors, Enantiornithes. P. Currie, Erenhot Dinosaur The Editors, Euornithopoda. E. Buffetaut, European Dinosaurs. J.D. Archibald, Evolution. J.D. Archibald, Extinction, Cretaceous. M.J. Benton, Extinction, Triassic. P. Guangzhao, Fabrosauridae. M. Lockley, Fatima. P. Currie, Feathered Dinosaurs. M. Lockley, Footprints and Trackways. Per Christiansen, Forelimbs and Hands. J.I. Kirkland, Fruita Paleontological Area. M.J. Ryan, Fruitland Formation. X-C. Wu, Functional Morphology. L. Claessens, Gastralia. D.D. Gillette, Gastroliths. The Editors, Genasauria. J.M. Parrish, Genetics. C.C. Swisher, Geologic Time. C. Coy, Ghost Ranch. K. Padian, Glen Canyon Group. D.A. Winkler, Glen Rose, Texas. P. Currie, Graduate Studies. D.J. Varricchio, Growth and Embryology. K. Padian, Growth Lines. C.A. Forster, Hadrosauridae. K.R. Johnson, Hell Creek Flora. D.F. Lofgren, Hell Creek Formation. F.E. Novas, Herrerasauridae. J.A. Long and K.J. McNamara, Heterochrony. J.B. Smith, Heterodontosauridae. Per Christiansen, Hind Limbs and Feet. R.E.H. Reid, Histology of Bones and Teeth. W.A.S. Sarjeant, History of Dinosaur Discoveries: Early Discoveries. B. Breithaupt, History of Dinosaur Discoveries: First Golden Period. E. Buffetaut, History of Dinosaur Discoveries: Quiet Times. L. Psihoyos, History of Dinosaur Discoveries: Research Today. B. Breithaupt, Howe Quarry. H-D. Sues, Hypsilophodontidae. C.A. Forster, Iguanodontidae. A. Sahni, Indian Dinosaurs. The Editors, Institute de Paleontologie, Museum National d'Histoire Naturelle, Paris, France. D. Zhiming, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China. D.A. Russell, Intelligence. R.R. Rogers, Ischigualasto Formation. Y. Azuma and Y. Tamida, Japanese Dinosaurs. D.A. Eberth, Judith River Wedge. D. Lessem and M. Schweitzer, Jurassic Park. P. Dodson, Jurassic Period. H. Haubold, Keuper Formation. M. Lockley, Khodja-Pil-Ata. M.J. Ryan, Kirtland Formation. A. Sahni, Lameta Formation. B. Breithaupt, Lance Formation. S.G. Lucas, Land-Mammal Ages. B.P. Perez-Moreno and J.L. Sanz, Las Hoyas. V.L. Santucci, Legislation Protecting Dinosaur Fossils. D.B. Weishampel, Life History. M. Lockley, Lommiswil. E. Frey and J. Martin, Long Necks of Sauropods. D. Zhiming, Lufeng. K. Padian, Maniraptora. K. Padian, Maniraptoriformes. The Editors, Marginocephalia. K. Padian, Megalosaurus. M. Lockley, Megatracksites. K. Padian, Mesozoic Era. H-D. Sues, Mesozoic Faunas. J. Basinger, Mesozoic Floras. R. Hernandez-Rivera, Mexican Dinosaurs. J.A. Schiebout, Microvertebrate Sites. M.J. Ryan, Middle Asian Dinosaurs. G.S. Paul, Migration. R. Barsbold, Mongolian Dinosaurs. K. Carpenter, Morrison Formation. J.M. Parrish, Musculature. J. Le Loeuff, Musee des Dinosaures, Esperaza, Aude, France. The Editors, Museum of Comparative Zoology, Harvard University. D.K. Smith, Museum of Earth Science, Brigham Young University. M. Schweitzer, Museum of the Rockies. D. Chure, Museums and Displays. A. Chinsamy, National Museum, Bloemfontein, South Africa. P. Davis, Natual History Museum, London. H. Osmolska, Nemegt Formation. P. Dodson, Neoceratopsia. The Editors, Neotetanurae. H-D. Sues, Newark Supergroup. K. Padian, Origin of Dinosaurs. L.B. Tatarinov, Orlov Museum of Paleontology. M.K. Vickaryous and M.J. Ryan, Ornamentation. K. Padian, Ornithischia. K. Padian, Ornithodira. H. Osmolska, Ornithomimosauria. The Editors, Ornithopoda. K. Padian, Ornithosuchia. R. Barsbold, Oviraptorosauria. J.B. Smith, Oxford Clay. H-D. Sues, Pachycephalosauria. H. Haubold, Paleoclimatology. P. Dodson, Paleoecology. J.F. Lerbekmo, Paleomagnetic Correlation. E.A. Buchholtz, Paleoneurology. P.J. Currie, Paleontogical Museum, Ulaan Baatar. P. Davis, Paleontology. D.H. Tanke and B.M. Rothschild, Paleopathology. K. Padian, Pectoral Girdle. D. Rasskin-Gutman, Pelvis, Comparative Anatomy. C. Trueman, Permineralization. J.M. Parrish, Petrified Forest. K. Padian, Phylogenetic System. K. Padian, Phylogeny of Dinosaurs. K. Padian, Physiology. B. Tiffney, Plants and Dinosaurs. E. Hoch, Plate Tectonics. T.H. Rich, R.A. Gangloff, and W.R. Hammer, Polar Dinosaurs. H. Osmolska, Polish-Mongolian Paleontological Expeditions. D.F. Glut, Popular Culture, Literature. P. Makovicky, Postcranial Axial Skeleton. B. Britt, Postcranial Pneumaticity. R.E. Molnar, Problems with the Fossil Record. P. Upchurch, Prosauropoda. P. Davis, Pseudofossils. K. Padian, Pseudosuchia. P. Sereno, Psittacosauridae. K. Padian, Pterosauria. K. Padian, Pterosauromopha. M. Lockney, Purgatoire. K. Padian, Quadrupedality. D.A. Eberth, Radiometric Dating. P. Currie, Raptors. S.J. Czerkas, Reconstruction and Restoration. G.S. Paul, Reproductive Behavior and Rates. M.J. Benton, Reptiles. J. Wright, Rocky Hill Dinosaur Park. H-D. Sues, Royal Ontario B.G. Naylor, Royal Tyrrell Museum of Palaeontology. M. Lockley, Samcheonpo. K. Padian, Saurischia. J.S. McIntosh, Sauropoda. P. Upchurch, Sauropodomorpha. P. Currie, Sino-Canadian Dinosaur Project. P. Currie, Sino-Soviet Expeditions. N.J. Mateer, Sino-Swedish Expeditions. E.H. Colbert, Size. R.M. Alexander, Size and Scaling. K. Padian, Skeletal Structures. S.A. Czerkas, Skin. The Editors, Skull, Comparative Anatomy. M.K. Brett-Surman, Smithsonian Institution. H. Haubold, Solnhofen Formation. A. Chinsamy, South African F.E. Novas, South American Dinosaurs. E. Buffetaut, Southeast Asian Dinosaurs. C. Coy, Soviet-Mongolian Paleontological Expeditions. J.D. Archibald, Speciation. J.D. Archibald, Species. A. Milner, Spinosauridae and Baryonychidae. The Editors, State Museum for Natural History, Stuttgart, Germany. K. Padian, Staurikosauridae. P. Galton, Stegosauria. X-C. Wu and A.P. Russell, Systematics. A.R. Fiorillo, Taphonomy. P.M. Sander, Teeth and Jaws. G. Maier, Tendaguru. J.R. Hutchinson and K. Padian, Tetanurae. K. Padian, Thecodontia. D.A. Russell, Therizinosauria. P.J. Currie, Theropoda. K. Carpenter, Thyreophora. A.R. Jacobsen, Tooth Marks. G.M. Erickson, Tooth Replacement Patterns. W.L. Abler, Tooth Serrations in Carnivorous Dinosaurs. A.R. Fiorillo and D.B. Weishampel, Tooth Wear. K. Padian, Trace Fossils. J.M. Parrish, Triassic Period. D.J. Varricchio, Troodontidae. J.O. Farlow, Trophic Groups. D.B. Weishampel, Trossingen. R.R. Rogers, Two Medicine Formation. K. Carpenter, Tyrannosauridae. M. Norell, Ukhaa Tolgod. The Editors, University of California Museum of Paleontology. S.D. Sampson and M.J. Ryan, Variation. M.J. Benton, Vertebrata. P. Davis, Vertebrate Paleontology. G.M. Erickson, Von Ebner Incremental Growth Lines. D. Norman, Wealden Group. J.R. Horner, Willow Creek Anticline. M.A. Turner, Yale Peabody D. Zhiming, Zigong Museum. Resources. Index.

@article{doi105860choice353642,
    title = "Encyclopedia of dinosaurs",
    year = "1998",
    journal = "Choice Reviews Online",
    abstract = "Thematic Table of Contents. Contributors. A Guide to Using the Encyclopedia. Michael Crichton, Foreword. Preface. Dedication. F.E. Novas, Abelisauridae. L.L. Jacobs, African Dinosaurs. G. Erickson, Age Determination. A. Chinsamy, Albany K. Padian and J.R. Hutchinson, Allosauroidea. P. Dodson, American Dinosaurs. L. Dingus, American Museum of Natural History. K. Carpenter, Ankylosauria. J.M. Parrish, Archosauria. J.R. Hutchinson and K. Padain, Arctometatarsalia. R.E. Molnar, Australasian Dinosaurs. L.M. Chiappe, Aves. The Editors, Avetheropoda. K. Padian, Avialae. H. Osmolska, Barun Goyot Formation. J.L. Sanz, Bastus Nesting Site. The Editors, Bavarian State Collection for Paleontology and Historical Geology. P. Currie, Bayan Mandahu. H. Osmolska, Bayn Dzak. J.R. Horner, Behavior. A. Chinsamy, Bernard Price Institute for Paleontological Research. J. Le Loeuff, Biogeography. R.M. Alexander, Biomechanics. R. Chapman, Biometrics. C. Trueman, Biomineralization. S.G. Lucas, Biostratigraphy. K. Padian, Bipedality. K. Padian, Bird Origins. B. Breithaupt, Bone Cabin Quarry. P. Currie, Braincase Anatomy. K. Padain and J.R. Hutchinson, Bullatosauria. M. Lockley, Cabo Espichel. J.S. Moratalla and J.L. Sanz, Cameros Basin Megatracksite. C. Coy, Canadian Dinosaurs. K. Carpenter, Canon City. M. Lockley, Carenque. J.S. McIntosh, Carnegie Museum of Natural History. J.R. Hutchinson and K. Padian, Carnosauria. J. Kirkland, Cedar Mountain Formation. M. Norell, Central Asiatic Expeditions. The Editors, Cerapoda. P. Dodson, Ceratopsia. T. Rowe, R. Tykoski, and J.R. Hutchinson, Ceratosauria. H. Bocherens, Chemical Composition of Dinosaur Fossils. D. Zhiming, Chinese Dinosaurs. J.M. Parrish, Chinle Formation. J.B. Smith, Cleveland-Lloyd Dinosaur Quarry. D. Maxwell, Cloverly Formation. J.R. Hutchinson and K. Padian, Coelurosauria. M.J. Ryan and A.P. Russell, Color. B. Breithaupt, Como Bluff. R.E. Chapman and D.B. Weishampel, Computers and Related Technology. J. Wright, Connecticut River Valley. D.B. Weishampel, Constructional Morphology. K. Chin, Coprolites. L.M. Witmer, Craniofacial Air Sinus Systems. E-B. Koppelhus, Cretaceous Period. J.M. Clark, Crocodylia. W.A.S. Sarjeant, Crystal Palace Dinosaurs. B. Britt and K.L. Stadtman, Dalton Wells Quarry. A. Sahni, Deccan Basalt. The Editors, Deinonychosauria. K. Carpenter, Denver Museum of Natural History. C. Coy, Devil's Coulee Dinosaur Egg Historic Site. M.J. Ryan and M.K. Vickaryous, Diet. K. Padian, Dinosauria: Definition. D. Chure, Dinosaur National Monument. A.B. Arcucci, Dinosauromorpha. C. Coy, Dinosaur Provincial Park. M. Lockley, Dinosaur Ridge. Don Lesson, Dinosaur Society. M. Lockley, Dinosaur Valley. M. Lockley, Dinoturbation. P. Dodson, Distribution and Diversity. T. Jerzykiewicz, Djadokhta Formation. P.A. Murry and R.A. Long, Dockum Group. P. Currie, Dromaeosaridae. B. Britt and B.I. Curtice, Dry Mesa Quarry. M.J. Ryan, Dryosauridae. D.A. Eberth, Edmonton Group. J.R. Horner, Egg Mountain. K.E. Mikhailov, Eggs, Eggshells, and Nests. P. Currie, Elmisauridae. The Editors, Enantiornithes. P. Currie, Erenhot Dinosaur The Editors, Euornithopoda. E. Buffetaut, European Dinosaurs. J.D. Archibald, Evolution. J.D. Archibald, Extinction, Cretaceous. M.J. Benton, Extinction, Triassic. P. Guangzhao, Fabrosauridae. M. Lockley, Fatima. P. Currie, Feathered Dinosaurs. M. Lockley, Footprints and Trackways. Per Christiansen, Forelimbs and Hands. J.I. Kirkland, Fruita Paleontological Area. M.J. Ryan, Fruitland Formation. X-C. Wu, Functional Morphology. L. Claessens, Gastralia. D.D. Gillette, Gastroliths. The Editors, Genasauria. J.M. Parrish, Genetics. C.C. Swisher, Geologic Time. C. Coy, Ghost Ranch. K. Padian, Glen Canyon Group. D.A. Winkler, Glen Rose, Texas. P. Currie, Graduate Studies. D.J. Varricchio, Growth and Embryology. K. Padian, Growth Lines. C.A. Forster, Hadrosauridae. K.R. Johnson, Hell Creek Flora. D.F. Lofgren, Hell Creek Formation. F.E. Novas, Herrerasauridae. J.A. Long and K.J. McNamara, Heterochrony. J.B. Smith, Heterodontosauridae. Per Christiansen, Hind Limbs and Feet. R.E.H. Reid, Histology of Bones and Teeth. W.A.S. Sarjeant, History of Dinosaur Discoveries: Early Discoveries. B. Breithaupt, History of Dinosaur Discoveries: First Golden Period. E. Buffetaut, History of Dinosaur Discoveries: Quiet Times. L. Psihoyos, History of Dinosaur Discoveries: Research Today. B. Breithaupt, Howe Quarry. H-D. Sues, Hypsilophodontidae. C.A. Forster, Iguanodontidae. A. Sahni, Indian Dinosaurs. The Editors, Institute de Paleontologie, Museum National d'Histoire Naturelle, Paris, France. D. Zhiming, Institute of Vertebrate Paleontology and Paleoanthropology, Beijing, China. D.A. Russell, Intelligence. R.R. Rogers, Ischigualasto Formation. Y. Azuma and Y. Tamida, Japanese Dinosaurs. D.A. Eberth, Judith River Wedge. D. Lessem and M. Schweitzer, Jurassic Park. P. Dodson, Jurassic Period. H. Haubold, Keuper Formation. M. Lockley, Khodja-Pil-Ata. M.J. Ryan, Kirtland Formation. A. Sahni, Lameta Formation. B. Breithaupt, Lance Formation. S.G. Lucas, Land-Mammal Ages. B.P. Perez-Moreno and J.L. Sanz, Las Hoyas. V.L. Santucci, Legislation Protecting Dinosaur Fossils. D.B. Weishampel, Life History. M. Lockley, Lommiswil. E. Frey and J. Martin, Long Necks of Sauropods. D. Zhiming, Lufeng. K. Padian, Maniraptora. K. Padian, Maniraptoriformes. The Editors, Marginocephalia. K. Padian, Megalosaurus. M. Lockley, Megatracksites. K. Padian, Mesozoic Era. H-D. Sues, Mesozoic Faunas. J. Basinger, Mesozoic Floras. R. Hernandez-Rivera, Mexican Dinosaurs. J.A. Schiebout, Microvertebrate Sites. M.J. Ryan, Middle Asian Dinosaurs. G.S. Paul, Migration. R. Barsbold, Mongolian Dinosaurs. K. Carpenter, Morrison Formation. J.M. Parrish, Musculature. J. Le Loeuff, Musee des Dinosaures, Esperaza, Aude, France. The Editors, Museum of Comparative Zoology, Harvard University. D.K. Smith, Museum of Earth Science, Brigham Young University. M. Schweitzer, Museum of the Rockies. D. Chure, Museums and Displays. A. Chinsamy, National Museum, Bloemfontein, South Africa. P. Davis, Natual History Museum, London. H. Osmolska, Nemegt Formation. P. Dodson, Neoceratopsia. The Editors, Neotetanurae. H-D. Sues, Newark Supergroup. K. Padian, Origin of Dinosaurs. L.B. Tatarinov, Orlov Museum of Paleontology. M.K. Vickaryous and M.J. Ryan, Ornamentation. K. Padian, Ornithischia. K. Padian, Ornithodira. H. Osmolska, Ornithomimosauria. The Editors, Ornithopoda. K. Padian, Ornithosuchia. R. Barsbold, Oviraptorosauria. J.B. Smith, Oxford Clay. H-D. Sues, Pachycephalosauria. H. Haubold, Paleoclimatology. P. Dodson, Paleoecology. J.F. Lerbekmo, Paleomagnetic Correlation. E.A. Buchholtz, Paleoneurology. P.J. Currie, Paleontogical Museum, Ulaan Baatar. P. Davis, Paleontology. D.H. Tanke and B.M. Rothschild, Paleopathology. K. Padian, Pectoral Girdle. D. Rasskin-Gutman, Pelvis, Comparative Anatomy. C. Trueman, Permineralization. J.M. Parrish, Petrified Forest. K. Padian, Phylogenetic System. K. Padian, Phylogeny of Dinosaurs. K. Padian, Physiology. B. Tiffney, Plants and Dinosaurs. E. Hoch, Plate Tectonics. T.H. Rich, R.A. Gangloff, and W.R. Hammer, Polar Dinosaurs. H. Osmolska, Polish-Mongolian Paleontological Expeditions. D.F. Glut, Popular Culture, Literature. P. Makovicky, Postcranial Axial Skeleton. B. Britt, Postcranial Pneumaticity. R.E. Molnar, Problems with the Fossil Record. P. Upchurch, Prosauropoda. P. Davis, Pseudofossils. K. Padian, Pseudosuchia. P. Sereno, Psittacosauridae. K. Padian, Pterosauria. K. Padian, Pterosauromopha. M. Lockney, Purgatoire. K. Padian, Quadrupedality. D.A. Eberth, Radiometric Dating. P. Currie, Raptors. S.J. Czerkas, Reconstruction and Restoration. G.S. Paul, Reproductive Behavior and Rates. M.J. Benton, Reptiles. J. Wright, Rocky Hill Dinosaur Park. H-D. Sues, Royal Ontario B.G. Naylor, Royal Tyrrell Museum of Palaeontology. M. Lockley, Samcheonpo. K. Padian, Saurischia. J.S. McIntosh, Sauropoda. P. Upchurch, Sauropodomorpha. P. Currie, Sino-Canadian Dinosaur Project. P. Currie, Sino-Soviet Expeditions. N.J. Mateer, Sino-Swedish Expeditions. E.H. Colbert, Size. R.M. Alexander, Size and Scaling. K. Padian, Skeletal Structures. S.A. Czerkas, Skin. The Editors, Skull, Comparative Anatomy. M.K. Brett-Surman, Smithsonian Institution. H. Haubold, Solnhofen Formation. A. Chinsamy, South African F.E. Novas, South American Dinosaurs. E. Buffetaut, Southeast Asian Dinosaurs. C. Coy, Soviet-Mongolian Paleontological Expeditions. J.D. Archibald, Speciation. J.D. Archibald, Species. A. Milner, Spinosauridae and Baryonychidae. The Editors, State Museum for Natural History, Stuttgart, Germany. K. Padian, Staurikosauridae. P. Galton, Stegosauria. X-C. Wu and A.P. Russell, Systematics. A.R. Fiorillo, Taphonomy. P.M. Sander, Teeth and Jaws. G. Maier, Tendaguru. J.R. Hutchinson and K. Padian, Tetanurae. K. Padian, Thecodontia. D.A. Russell, Therizinosauria. P.J. Currie, Theropoda. K. Carpenter, Thyreophora. A.R. Jacobsen, Tooth Marks. G.M. Erickson, Tooth Replacement Patterns. W.L. Abler, Tooth Serrations in Carnivorous Dinosaurs. A.R. Fiorillo and D.B. Weishampel, Tooth Wear. K. Padian, Trace Fossils. J.M. Parrish, Triassic Period. D.J. Varricchio, Troodontidae. J.O. Farlow, Trophic Groups. D.B. Weishampel, Trossingen. R.R. Rogers, Two Medicine Formation. K. Carpenter, Tyrannosauridae. M. Norell, Ukhaa Tolgod. The Editors, University of California Museum of Paleontology. S.D. Sampson and M.J. Ryan, Variation. M.J. Benton, Vertebrata. P. Davis, Vertebrate Paleontology. G.M. Erickson, Von Ebner Incremental Growth Lines. D. Norman, Wealden Group. J.R. Horner, Willow Creek Anticline. M.A. Turner, Yale Peabody D. Zhiming, Zigong Museum. Resources. Index.",
    url = "https://doi.org/10.5860/choice.35-3642",
    doi = "10.5860/choice.35-3642",
    openalex = "W647458292"
}

ABSTRACT An unusual trace containing eggs of the 50 kg-plus theropod dinosaur, Troodon formosus, represents one of the best preserved dinosaur nests. This unique specimen (MOR 963) represents the actual nest structure and the direct product of Troodon behavior. The trace comes from the Campanian, Late Cretaceous Two Medicine Formation of Montana, and consists of a bowl-shaped depression with an internal area of ~1m2 surrounded by a distinct rim. A clutch of 24 tightly-placed eggs sat in the center and both nest and clutch show bilateral symmetry about a north–south axis. The trace occurs within a moderately well-developed micritic paleosol. A physically and chemically distinct mudstone covered the nest and represents overbank deposition. The nest protected the eggs by creating a suitable micro-environment during the lengthy egg-laying and incubation periods. Clutch and nest size, shape, and symmetry and low organic carbon of the overlying mudstone suggests brooding rather than incubation with vegetative cover, although the latter cannot be ruled out. The nest probably played no role in the post-hatching care of precocial Troodon young. Reproductive traits indicated by MOR 963 show that Troodon possessed plesiomorphies shared with crocodilians (some burial of eggs and lack of egg rotation), apomorphies shared with birds (open nests, exposed eggs, and incubation by a brooding adult), but also at least one unusual feature (steeply-inclined eggs) not found in either extant archosaur group. Some reproductive features typically associated with living birds first evolved within non-avian coelurosaurian theropods like Troodon.

@article{doi10108002724634199910011125,
    author = "Varricchio, David J. and Jackson, Frankie D. and Trueman, Clive N.",
    title = "A nesting trace with eggs for the Cretaceous theropod dinosaur Troodon formosus",
    year = "1999",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "ABSTRACT An unusual trace containing eggs of the 50 kg-plus theropod dinosaur, Troodon formosus, represents one of the best preserved dinosaur nests. This unique specimen (MOR 963) represents the actual nest structure and the direct product of Troodon behavior. The trace comes from the Campanian, Late Cretaceous Two Medicine Formation of Montana, and consists of a bowl-shaped depression with an internal area of \textasciitilde 1m2 surrounded by a distinct rim. A clutch of 24 tightly-placed eggs sat in the center and both nest and clutch show bilateral symmetry about a north–south axis. The trace occurs within a moderately well-developed micritic paleosol. A physically and chemically distinct mudstone covered the nest and represents overbank deposition. The nest protected the eggs by creating a suitable micro-environment during the lengthy egg-laying and incubation periods. Clutch and nest size, shape, and symmetry and low organic carbon of the overlying mudstone suggests brooding rather than incubation with vegetative cover, although the latter cannot be ruled out. The nest probably played no role in the post-hatching care of precocial Troodon young. Reproductive traits indicated by MOR 963 show that Troodon possessed plesiomorphies shared with crocodilians (some burial of eggs and lack of egg rotation), apomorphies shared with birds (open nests, exposed eggs, and incubation by a brooding adult), but also at least one unusual feature (steeply-inclined eggs) not found in either extant archosaur group. Some reproductive features typically associated with living birds first evolved within non-avian coelurosaurian theropods like Troodon.",
    url = "https://doi.org/10.1080/02724634.1999.10011125",
    doi = "10.1080/02724634.1999.10011125",
    openalex = "W2026000490",
    references = "doi1010029780470698716, doi101007bf00344996, doi101016s0195667105800308, doi101038282296a0, doi101038378774a0, doi101038385247a0, doi10108002724634199510011271, doi101130spe216p1, doi10129879780300237856, openalexw657672288, sereno1997the"
}

Infoquest Foundation, 160 Cabrini Boulevard #48, New York, New York 10033, U.S.AINTRODUCTIONAbelisaur dinosaurs, theropods with unusual horned skullssuch as Majungatholus (Sampson et al., 1998) and Carnotaurus(Bonaparte, 1985), are the most abundant land predators fromthe Late Cretaceous of Gondwana (Bonaparte, 1996; Novas,1997; Sampson et al., 1998; Coria and Salgado, 1998). Al-though a number of abelisaur species are known from Argentina(Bonaparte, 1996), as well as India and Madagascar (Sampsonet al., 1998), much of their anatomy and evolutionary relation-ships remains poorly understood.In March of 1999, a joint expedition from the Museo Mu-nicipal Carmen Funes and the Natural History Museum of LosAngeles County recovered a nearly complete and articulatedskeleton of a large theropod from Auca Mahuevo, a PatagonianLate Cretaceous site famous for its abundant sauropod eggs andembryos (Chiappe et al., 1998, 2000). In spite of being 30%smaller, the Auca Mahuevo theropod is remarkably similar toCarnotaurus sastrei (Bonaparte, 1985). Nonetheless, a uniquecombination of characters distinguishes the new skeleton fromCarnotaurus sastrei. Thus, following the predicates of the phy-logenetic species concept (Nixon and Wheeler, 1992), the AucaMahuevo skeleton forms the basis for a new abelisaur species,Aucasaurus garridoi.GEOLOGICAL SETTINGThe 150 m-thick section at Auca Mahuevo containing Au-casaurus garridoi runs transitionally from the Anacleto Mem-ber of the Ri´o Colorado Formation up through the Allen For-mation (Fig. 1A). The lower 85 m of the section that comprisesthe Anacleto portion is composed predominantly of pale reddishbrown, fine-grained sandstone, siltstone and mudstone, punc-tuated with occasional beds of greenish gray to light bluishgray, micaceous sandstone. These units appear to represent flu-vial channels and adjacent overbank deposits laid down acrossa low-gradient floodplain (Chiappe et al., 1998; Dingus et al.,2000). The lowest 45 m contain four levels of mudstone andsiltstone that produce fossilized eggs, embryos and embryonicskin of neosauropods (Chiappe et al., 2000). The lowest 20 moccur in a reversed magnetozone tentatively correlated withC33r in the early to middle Campanian portion of the Geomag-netic Polarity Timescale (Dingus et al., 2000). The new speci-men described here was found in an unusual laminated unit,composed by varves of unknown periodicity of greenish graymudstone and very fine-grained sandstone about 70 m abovethe base of the section near the top of the exposures of theAnacleto Member. This bed appears to represent a shallow wa-ter, lacustrine deposit based on the well-developed laminae andthe presence of freshwater arthropods.Institutional Abbreviations MCF-PVPH, Museo Munic-ipal Carmen Funes, Paleontologi´a de Vertebrados, Plaza Huin-cul, Argentina; MACN-CH, Museo Argentino de Ciencias Na-turales, Coleccio´n Chubut, Buenos Aires, Argentina.SYSTEMATIC PALEONTOLOGYTHEROPODA Marsh, 1881ABELISAURIA Novas, 1992ABELISAUROIDEA Novas, 1989ABELISAURIDAE Bonaparte and Novas, 1985CARNOTAURINAE Sereno, 1998CARNOTAURINI new taxonPhylogenetic Definition Carnotaurini is phylogeneticallydefined as the common ancestor of Carnotaurus sastrei andAucasaurus garridoi plus all the descendants of this ancestor.Diagnosis Two unambiguous synapomorphies support themonophyly of carnotaurs (term used to refer to members of theCarnotaurini): the presence of hyposphene–hypantrum articu-lations in the proximal and middle sections of the caudal series,and cranial processes in the epipophyses of the cervical verte-brae. Several other synapomorphies provide further support forthe monophyly of carnotaurs. These, however, are ambiguouslyoptimized because they are not preserved in other abelisaurs.These ambiguous synapomorphies include: a very broad cora-coid (coracoid maximum width three times the distance acrossthe scapular glenoid area), a humerus with a large and hemi-spherical head, an extremely short ulna and radius (ulna to hu-merus ratio 1:3 or less), and frontal prominences (swells orhorns) that are located laterally on the skull roof.Aucasaurus garridoi new taxonEtymology ‘‘Auca,’’ from Mapuche language, in referenceto Auca Mahuevo, the fossil locality where the specimen wasfound; ‘‘saurus,’’ from the Greek, lizard; ‘‘garridoi,’’ in hom-age to Mr. Alberto Garrido, who discovered the holotype.Holotype MCF-PVPH-236 was found lying on its rightside and articulated from the skull to the middle section of thetail (13

@article{doi1016710272463420020220460ancroc20co2,
    author = "Coria, Rodolfo A. and Chiappe, Luis M. and Dingus, Lowell",
    title = "A new close relative of Carnotaurus sastrei Bonaparte 1985 (Theropoda: Abelisauridae) from the Late Cretaceous of Patagonia",
    year = "2002",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "Infoquest Foundation, 160 Cabrini Boulevard \#48, New York, New York 10033, U.S.AINTRODUCTIONAbelisaur dinosaurs, theropods with unusual horned skullssuch as Majungatholus (Sampson et al., 1998) and Carnotaurus(Bonaparte, 1985), are the most abundant land predators fromthe Late Cretaceous of Gondwana (Bonaparte, 1996; Novas,1997; Sampson et al., 1998; Coria and Salgado, 1998). Al-though a number of abelisaur species are known from Argentina(Bonaparte, 1996), as well as India and Madagascar (Sampsonet al., 1998), much of their anatomy and evolutionary relation-ships remains poorly understood.In March of 1999, a joint expedition from the Museo Mu-nicipal Carmen Funes and the Natural History Museum of LosAngeles County recovered a nearly complete and articulatedskeleton of a large theropod from Auca Mahuevo, a PatagonianLate Cretaceous site famous for its abundant sauropod eggs andembryos (Chiappe et al., 1998, 2000). In spite of being 30\%smaller, the Auca Mahuevo theropod is remarkably similar toCarnotaurus sastrei (Bonaparte, 1985). Nonetheless, a uniquecombination of characters distinguishes the new skeleton fromCarnotaurus sastrei. Thus, following the predicates of the phy-logenetic species concept (Nixon and Wheeler, 1992), the AucaMahuevo skeleton forms the basis for a new abelisaur species,Aucasaurus garridoi.GEOLOGICAL SETTINGThe 150 m-thick section at Auca Mahuevo containing Au-casaurus garridoi runs transitionally from the Anacleto Mem-ber of the Ri´o Colorado Formation up through the Allen For-mation (Fig. 1A). The lower 85 m of the section that comprisesthe Anacleto portion is composed predominantly of pale reddishbrown, fine-grained sandstone, siltstone and mudstone, punc-tuated with occasional beds of greenish gray to light bluishgray, micaceous sandstone. These units appear to represent flu-vial channels and adjacent overbank deposits laid down acrossa low-gradient floodplain (Chiappe et al., 1998; Dingus et al.,2000). The lowest 45 m contain four levels of mudstone andsiltstone that produce fossilized eggs, embryos and embryonicskin of neosauropods (Chiappe et al., 2000). The lowest 20 moccur in a reversed magnetozone tentatively correlated withC33r in the early to middle Campanian portion of the Geomag-netic Polarity Timescale (Dingus et al., 2000). The new speci-men described here was found in an unusual laminated unit,composed by varves of unknown periodicity of greenish graymudstone and very fine-grained sandstone about 70 m abovethe base of the section near the top of the exposures of theAnacleto Member. This bed appears to represent a shallow wa-ter, lacustrine deposit based on the well-developed laminae andthe presence of freshwater arthropods.Institutional Abbreviations MCF-PVPH, Museo Munic-ipal Carmen Funes, Paleontologi´a de Vertebrados, Plaza Huin-cul, Argentina; MACN-CH, Museo Argentino de Ciencias Na-turales, Coleccio´n Chubut, Buenos Aires, Argentina.SYSTEMATIC PALEONTOLOGYTHEROPODA Marsh, 1881ABELISAURIA Novas, 1992ABELISAUROIDEA Novas, 1989ABELISAURIDAE Bonaparte and Novas, 1985CARNOTAURINAE Sereno, 1998CARNOTAURINI new taxonPhylogenetic Definition Carnotaurini is phylogeneticallydefined as the common ancestor of Carnotaurus sastrei andAucasaurus garridoi plus all the descendants of this ancestor.Diagnosis Two unambiguous synapomorphies support themonophyly of carnotaurs (term used to refer to members of theCarnotaurini): the presence of hyposphene–hypantrum articu-lations in the proximal and middle sections of the caudal series,and cranial processes in the epipophyses of the cervical verte-brae. Several other synapomorphies provide further support forthe monophyly of carnotaurs. These, however, are ambiguouslyoptimized because they are not preserved in other abelisaurs.These ambiguous synapomorphies include: a very broad cora-coid (coracoid maximum width three times the distance acrossthe scapular glenoid area), a humerus with a large and hemi-spherical head, an extremely short ulna and radius (ulna to hu-merus ratio 1:3 or less), and frontal prominences (swells orhorns) that are located laterally on the skull roof.Aucasaurus garridoi new taxonEtymology ‘‘Auca,’’ from Mapuche language, in referenceto Auca Mahuevo, the fossil locality where the specimen wasfound; ‘‘saurus,’’ from the Greek, lizard; ‘‘garridoi,’’ in hom-age to Mr. Alberto Garrido, who discovered the holotype.Holotype MCF-PVPH-236 was found lying on its rightside and articulated from the skull to the middle section of thetail (13",
    url = "https://doi.org/10.1671/0272-4634(2002)022[0460:ancroc]2.0.co;2",
    doi = "10.1671/0272-4634(2002)022[0460:ancroc]2.0.co;2",
    openalex = "W2175280492",
    references = "crossref1976allosaurus, doi10103824370, doi101126science28053661048, doi101126science28454232137, doi1012060003008220002900001samfcf20co2, doi105860choice353642, doi105962p226819, openalexw1426920053, openalexw3183813916, openalexw592572837"
}

Abstract We describe the osteology of the new small theropod dinosaur Masiakasaurus knopfleri, from the Late Cretaceous Maevarano Formation of northwestern Madagascar. Approximately 40% of the skeleton is known, including parts of the jaws, axial column, forelimb, pelvic girdle, and hind limb. The jaws of Masiakasaurus are remarkably derived, bearing a heterodont, procumbent dentition that is unknown elsewhere among dinosaurs. The vertebrae are similar to those of abelisauroids in the reduction of the neural spine, lack of pleurocoelous fossae on the centrum, and extensively pneumatized neural arch. The limb skeleton is relatively gracile and bears numerous abelisauroid synapomorphies, including a rounded humeral head, peg-and-socket iliac-pubic articulation, prominent femoral medial epicondyle, expanded tibial cnemial crest, and double-grooved pedal unguals. The femora and tibiae show evidence of dimorphism. More specific features shared between Masiakasaurus, the Argentine Noasaurus, and the Indian Laevisuchus suggest that these taxa form a clade (Noasauridae) within Abelisauroidea. This is supported by a cladistic phylogenetic analysis of 158 characters and 23 theropod taxa. Additionally, Ceratosauria is rendered paraphyletic in favor of a sister-taxon relationship between Neoceratosauria and Tetanurae that is exclusive of Coelophysoidea. The unique dental and jaw specializations of Masiakasaurus suggest deviation from the typical theropod diet. Finally, the distribution of noasaurids further supports a shared biogeographic history between South America, Madagascar, and India into the Late Cretaceous.

@article{doi1016710272463420020220510toomka20co2,
    author = "Carrano, Matthew T. and Sampson, Scott D. and Forster, Catherine A.",
    title = "The osteology of Masiakasaurus knopfleri, a small abelisauroid (Dinosauria: Theropoda) from the Late Cretaceous of Madagascar",
    year = "2002",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "Abstract We describe the osteology of the new small theropod dinosaur Masiakasaurus knopfleri, from the Late Cretaceous Maevarano Formation of northwestern Madagascar. Approximately 40\% of the skeleton is known, including parts of the jaws, axial column, forelimb, pelvic girdle, and hind limb. The jaws of Masiakasaurus are remarkably derived, bearing a heterodont, procumbent dentition that is unknown elsewhere among dinosaurs. The vertebrae are similar to those of abelisauroids in the reduction of the neural spine, lack of pleurocoelous fossae on the centrum, and extensively pneumatized neural arch. The limb skeleton is relatively gracile and bears numerous abelisauroid synapomorphies, including a rounded humeral head, peg-and-socket iliac-pubic articulation, prominent femoral medial epicondyle, expanded tibial cnemial crest, and double-grooved pedal unguals. The femora and tibiae show evidence of dimorphism. More specific features shared between Masiakasaurus, the Argentine Noasaurus, and the Indian Laevisuchus suggest that these taxa form a clade (Noasauridae) within Abelisauroidea. This is supported by a cladistic phylogenetic analysis of 158 characters and 23 theropod taxa. Additionally, Ceratosauria is rendered paraphyletic in favor of a sister-taxon relationship between Neoceratosauria and Tetanurae that is exclusive of Coelophysoidea. The unique dental and jaw specializations of Masiakasaurus suggest deviation from the typical theropod diet. Finally, the distribution of noasaurids further supports a shared biogeographic history between South America, Madagascar, and India into the Late Cretaceous.",
    url = "https://doi.org/10.1671/0272-4634(2002)022[0510:toomka]2.0.co;2",
    doi = "10.1671/0272-4634(2002)022[0510:toomka]2.0.co;2",
    openalex = "W2180522875",
    references = "crossref1998encyclopedia, doi101002jmor10018, doi101017cbo9780511608377010, doi10108002724634199510011574, doi10108002724634199610011283, doi101086273307, doi101111j109636422001tb01313x, doi101126science28253921298, doi101126science28454232137, doi10113008137233291, doi101130gsat19991001science, doi1015468gbdyof, doi1023073514816, doi105281zenodo13648988, doi105281zenodo16171435, doi105281zenodo16692311, doi105860choice263889, doi105860choice353642, openalexw2173200745, openalexw3217097258"
}

ABSTRACT The holotype of Irritator challengeri Martill et al., 1996 from the Romualdo Member of the Santana Formation (Lower Cretaceous) in northeastern Brazil represents the most complete skull of a spinosaurid known to date. The now fully prepared specimen provides much new information on the cranial structure in these enigmatic predatory dinosaurs. The skull is remarkably narrow, especially in the region of the elongated snout. The maxillae are in broad contact along the midline, forming an extensive secondary bony palate. The maxillary teeth have straight or slightly recurved, conical crowns, with thin, fluted enamel and distinct but smooth carinae. As in Baryonyx walkeri, the anterior and ventral processes of the lacrimai meet at a more acute angle than in most non-avian theropod dinosaurs. The braincase is short anteroposteriorly but deep dorsoventrally, extending ventrally far below the occipital condyle. Irritator challengeri most closely resembles Spinosaurus aegyptiacus in the structure of its teeth, but more extensive comparisons between the two taxa are currently impossible due to the limited amount of cranial material known for the latter.

@article{doi1016710272463420020220535icasdt20co2,
    author = "Sues, Hans‐Dieter and Frey, Eberhard and Martill, David M. and Scott, Diane",
    title = "Irritator challengeri, a spinosaurid (Dinosauria: Theropoda) from the Lower Cretaceous of Brazil",
    year = "2002",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "ABSTRACT The holotype of Irritator challengeri Martill et al., 1996 from the Romualdo Member of the Santana Formation (Lower Cretaceous) in northeastern Brazil represents the most complete skull of a spinosaurid known to date. The now fully prepared specimen provides much new information on the cranial structure in these enigmatic predatory dinosaurs. The skull is remarkably narrow, especially in the region of the elongated snout. The maxillae are in broad contact along the midline, forming an extensive secondary bony palate. The maxillary teeth have straight or slightly recurved, conical crowns, with thin, fluted enamel and distinct but smooth carinae. As in Baryonyx walkeri, the anterior and ventral processes of the lacrimai meet at a more acute angle than in most non-avian theropod dinosaurs. The braincase is short anteroposteriorly but deep dorsoventrally, extending ventrally far below the occipital condyle. Irritator challengeri most closely resembles Spinosaurus aegyptiacus in the structure of its teeth, but more extensive comparisons between the two taxa are currently impossible due to the limited amount of cranial material known for the latter.",
    url = "https://doi.org/10.1671/0272-4634(2002)022[0535:icasdt]2.0.co;2",
    doi = "10.1671/0272-4634(2002)022[0535:icasdt]2.0.co;2",
    openalex = "W2148668827",
    references = "doi101038324359a0, doi101144gsjgs15310005"
}

Synopsis The dinosaurs of the Hateg Basin of Transylvania (late Maastrichtian; western Romania) include Theropoda, Sauropoda, Ornithopoda and Ankylosauria. Of these, one of the most enigmatic taxa is the ornithopod that Franz Baron Nopcsa originally described as Mochlodon suessi and M. robustus in 1902. These two species have come to be regarded as a single species of Rhabdodon, R. robustus, which is distinct from R. priscus from the Late Cretaceous of southern France and northern Spain. This study provides a detailed anatomical revision of the Rhabdodon material that was described originally by Nopcsa during the early decades of the 20th century. It also adds information on material discovered in the Hateg area of Romania since the 1930s. A phylogenetic analysis of basal euornithopods indicates that the non‐hadrosaurid material from Hateg comprises two distinct, but congeneric, species. These two species can be distinguished unambiguously from R. priscus. A new genus Zalmoxes is established for the Romanian ornithopod, comprising Z. robustus comb. nov. (the type‐species of the genus) and Z. shqiperorum sp. nov. Phylogenetic analysis indicates that the two species of Zalmoxes and R. priscus are united in the monophyletic clade Rhabdodontidae (nov.). Rhabdodontidae constitutes the sibling clade to Iguanodontia. R. septimanicus, M. suessi, and the Villeveyrac Rhabdodon also appear to be members of Rhabdodontidae. The evolutionary implications of this phylogenetic analysis include the recognition of a ghost lineage, extending from the most recent common ancestor of Rhabdodontidae and Iguanodontia, which extends for 73 million years. This extraordinarily long ghost lineage duration may reflect considerable gaps in the history of this group or the geographical isolation of Rhabdodontidae in Europe during much of the Cretaceous period. The area of origin of the Rhabdodontidae + Iguanodontia clade may be North America, while the common ancestor of Rhabdodontidae dispersed to Europe, at that time a marine‐dominated region with tectonically‐active terrestrial habitats. Adult individuals of Z. robustus are smaller than either of its two closest relatives, Z. shqiperorum and R. priscus, within the Rhabdodontidae, or with many species of Iguanodontia and, therefore, is considered a possible paedomorphic dwarf.

@article{doi101017s1477201903001032,
    author = "Weishampel, David B. and Jianu, Coralia‐Maria and Csiki‐Sava, Zoltán and Norman, David",
    title = "Osteology and phylogeny of Zalmoxes (n. g.), an unusual Euornithopod dinosaur from the latest Cretaceous of Romania",
    year = "2003",
    journal = "Journal of Systematic Palaeontology",
    abstract = "Synopsis The dinosaurs of the Hateg Basin of Transylvania (late Maastrichtian; western Romania) include Theropoda, Sauropoda, Ornithopoda and Ankylosauria. Of these, one of the most enigmatic taxa is the ornithopod that Franz Baron Nopcsa originally described as Mochlodon suessi and M. robustus in 1902. These two species have come to be regarded as a single species of Rhabdodon, R. robustus, which is distinct from R. priscus from the Late Cretaceous of southern France and northern Spain. This study provides a detailed anatomical revision of the Rhabdodon material that was described originally by Nopcsa during the early decades of the 20th century. It also adds information on material discovered in the Hateg area of Romania since the 1930s. A phylogenetic analysis of basal euornithopods indicates that the non‐hadrosaurid material from Hateg comprises two distinct, but congeneric, species. These two species can be distinguished unambiguously from R. priscus. A new genus Zalmoxes is established for the Romanian ornithopod, comprising Z. robustus comb. nov. (the type‐species of the genus) and Z. shqiperorum sp. nov. Phylogenetic analysis indicates that the two species of Zalmoxes and R. priscus are united in the monophyletic clade Rhabdodontidae (nov.). Rhabdodontidae constitutes the sibling clade to Iguanodontia. R. septimanicus, M. suessi, and the Villeveyrac Rhabdodon also appear to be members of Rhabdodontidae. The evolutionary implications of this phylogenetic analysis include the recognition of a ghost lineage, extending from the most recent common ancestor of Rhabdodontidae and Iguanodontia, which extends for 73 million years. This extraordinarily long ghost lineage duration may reflect considerable gaps in the history of this group or the geographical isolation of Rhabdodontidae in Europe during much of the Cretaceous period. The area of origin of the Rhabdodontidae + Iguanodontia clade may be North America, while the common ancestor of Rhabdodontidae dispersed to Europe, at that time a marine‐dominated region with tectonically‐active terrestrial habitats. Adult individuals of Z. robustus are smaller than either of its two closest relatives, Z. shqiperorum and R. priscus, within the Rhabdodontidae, or with many species of Iguanodontia and, therefore, is considered a possible paedomorphic dwarf.",
    url = "https://doi.org/10.1017/s1477201903001032",
    doi = "10.1017/s1477201903001032",
    openalex = "W2167550757",
    references = "doi10100797836426953391, doi10103835059070, doi10108002724634199010011815, doi101086284406, doi101098rspl18870117, doi101111j109636421998tb02533x, doi101126science27352791204, doi102307jctvxkn7tk, doi102475ajss321125417, doi105479si00963801361666197, openalexw51761775, openalexw575814759"
}

Rauhut, Oliver W. M. (2003): The interrelationships and evolution of basal theropod dinosaurs. Special papers in palaeontology 69: 1-213, DOI: 10.5281/zenodo.3382576

@book{doi1015468gbdyof,
    author = "Rauhut, Oliver W. M.",
    title = "The interrelationships and evolution of basal theropod dinosaurs",
    year = "2003",
    abstract = "Rauhut, Oliver W. M. (2003): The interrelationships and evolution of basal theropod dinosaurs. Special papers in palaeontology 69: 1-213, DOI: 10.5281/zenodo.3382576",
    url = "https://doi.org/10.15468/gbdyof",
    doi = "10.15468/gbdyof",
    openalex = "W69964179"
}

Currie, Philip J. (2003): Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada. Palaeontologica Polonica 48 (2): 191-226, DOI: 10.5281/zenodo.3725717, URL: https://www.app.pan.pl/archive/published/app48/app48-191.pdf

@article{doi105281zenodo3725717,
    author = "Currie, Philip J.",
    title = "Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada",
    year = "2003",
    journal = "reroDoc Digital Library",
    abstract = "Currie, Philip J. (2003): Cranial anatomy of tyrannosaurid dinosaurs from the Late Cretaceous of Alberta, Canada. Palaeontologica Polonica 48 (2): 191-226, DOI: 10.5281/zenodo.3725717, URL: https://www.app.pan.pl/archive/published/app48/app48-191.pdf",
    url = "https://doi.org/10.5281/zenodo.3725717",
    doi = "10.5281/zenodo.3725717",
    openalex = "W2107092189",
    references = "carr1999craniofacial, crossref1976allosaurus, currie1985cranial, doi101017cbo9780511608377011, doi101038358059a0, doi10108002724634199510011574, doi10108002724634199710011027, doi10108002724634199910011161, doi101139e02083, doi1015468lnfamn, doi1015468yhxmzl, doi1023071292217, doi1023073514548, doi1034191b109, doi104095101672, doi105281zenodo1037529, doi105281zenodo1040973, doi105281zenodo1048848, doi105281zenodo814935, vonhuene1923carnivorous"
}

Abelisauroid predators have been recorded almost exclusively from South America, India and Madagascar, a distribution thought to document persistent land connections exclusive of Africa. Here, we report fossils from three stratigraphic levels in the Cretaceous of Niger that provide definitive evidence that abelisauroid dinosaurs and their immediate antecedents were also present on Africa. The fossils include an immediate abelisauroid antecedent of Early Cretaceous age (ca. 130-110 Myr ago), early members of the two abelisauroid subgroups (Noasauridae, Abelisauridae) of Mid-Cretaceous age (ca. 110 Myr ago) and a hornless abelisaurid skull of early Late Cretaceous age (ca. 95 Myr ago). Together, these fossils fill in the early history of the abelisauroid radiation and provide key evidence for continued faunal exchange among Gondwanan landmasses until the end of the Early Cretaceous (ca. 100 Myr ago).

@article{doi101098rspb20042692,
    author = "Sereno, Paul C. and Wilson, Jeffrey A. and Conrad, Jack L.",
    title = "New dinosaurs link southern landmasses in the Mid–Cretaceous",
    year = "2004",
    journal = "Proceedings of the Royal Society B Biological Sciences",
    abstract = "Abelisauroid predators have been recorded almost exclusively from South America, India and Madagascar, a distribution thought to document persistent land connections exclusive of Africa. Here, we report fossils from three stratigraphic levels in the Cretaceous of Niger that provide definitive evidence that abelisauroid dinosaurs and their immediate antecedents were also present on Africa. The fossils include an immediate abelisauroid antecedent of Early Cretaceous age (ca. 130-110 Myr ago), early members of the two abelisauroid subgroups (Noasauridae, Abelisauridae) of Mid-Cretaceous age (ca. 110 Myr ago) and a hornless abelisaurid skull of early Late Cretaceous age (ca. 95 Myr ago). Together, these fossils fill in the early history of the abelisauroid radiation and provide key evidence for continued faunal exchange among Gondwanan landmasses until the end of the Early Cretaceous (ca. 100 Myr ago).",
    url = "https://doi.org/10.1098/rspb.2004.2692",
    doi = "10.1098/rspb.2004.2692",
    openalex = "W2165747516",
    references = "doi1010160025322777900457, doi10103835016061, doi101126science2725264986, doi101126science28053661048, doi101126science28253921298, doi1016710272463420020220460ancroc20co2, doi1016710272463420020220510toomka20co2, doi105860choice331556, doi105962p226819, openalexw3114518543, openalexw3214948090"
}

Isolated theropod teeth are common Mesozoic fossils and would be an important data source for paleoecology biogeography if they could be reliably identified as having come from particular taxa. However, obtaining identifications is confounded by a paucity of easily identifiable characters. Here we discuss a quantitative methodology designed to provide defensible identifications of isolated teeth using Tyrannosaurus as a comparison taxon. We created a standard data set based as much as possible on teeth of known taxonomic affinity against which to compare isolated crowns. Tooth morphology was described using measured variables describing crown length, base length and width, and derived variables related to basal shape, squatness, mesial curve shape, apex location with respect to base, and denticle size. Crown curves were described by fitting the power function Y = a + bX(0.5) to coordinate data collected from lateral-view images of mesial curve profiles. The b value from these analyses provides a measure of curvature. Discriminant analyses compared isolated teeth of various taxonomic affinities against the standard. The analyses classified known Tyrannosaurus teeth with Tyrannosaurus and separated most teeth known not to be Tyrannosaurus from Tyrannosaurus. They had trouble correctly classifying teeth that were very similar to Tyrannosaurus and for which there were few data in the standard. However, the results indicate that expanding the standard should facilitate the identification of numerous types of isolated theropod teeth.

@article{doi101002ara20206,
    author = "Smith, Joshua B. and Vann, David R. and Dodson, Peter",
    title = "Dental morphology and variation in theropod dinosaurs: Implications for the taxonomic identification of isolated teeth",
    year = "2005",
    journal = "The Anatomical Record Part A Discoveries in Molecular Cellular and Evolutionary Biology",
    abstract = "Isolated theropod teeth are common Mesozoic fossils and would be an important data source for paleoecology biogeography if they could be reliably identified as having come from particular taxa. However, obtaining identifications is confounded by a paucity of easily identifiable characters. Here we discuss a quantitative methodology designed to provide defensible identifications of isolated teeth using Tyrannosaurus as a comparison taxon. We created a standard data set based as much as possible on teeth of known taxonomic affinity against which to compare isolated crowns. Tooth morphology was described using measured variables describing crown length, base length and width, and derived variables related to basal shape, squatness, mesial curve shape, apex location with respect to base, and denticle size. Crown curves were described by fitting the power function Y = a + bX(0.5) to coordinate data collected from lateral-view images of mesial curve profiles. The b value from these analyses provides a measure of curvature. Discriminant analyses compared isolated teeth of various taxonomic affinities against the standard. The analyses classified known Tyrannosaurus teeth with Tyrannosaurus and separated most teeth known not to be Tyrannosaurus from Tyrannosaurus. They had trouble correctly classifying teeth that were very similar to Tyrannosaurus and for which there were few data in the standard. However, the results indicate that expanding the standard should facilitate the identification of numerous types of isolated theropod teeth.",
    url = "https://doi.org/10.1002/ar.a.20206",
    doi = "10.1002/ar.a.20206",
    openalex = "W2057683116",
    references = "brinkman1990paleooecology, carr1999craniofacial, crossref1976allosaurus, doi101007bf02987808, doi1010160031018271900447, doi101016s0016699588800664, doi101017cbo9780511608377011, doi101017s0094837300013956, doi101038324359a0, doi101073pnas932514623, doi10108002724634198710011638, doi10108002724634199510011574, doi10108002724634199910011161, doi101098rspb20042692, doi101111j109636421978tb01049x, doi101111j10963642200400130x, doi101126science28454232137, doi101130gsat19991001science, doi101144gsjgs15310005, doi10129879781933789439, doi1015468gcrned, doi1016660022336020010750208lcsdaf20co2, doi1016660022336020020760751stabtf20co2, doi101671027246342003231apfast20co2, doi1016710272463420050250865hitrif20co2, doi1023072421859, doi1023073001469, doi1023073514548, doi1023073514695, doi102307jctvqc6gzx, doi102307jctvxkn7tk, doi10310210769986001002113, doi105281zenodo1040973, doi105281zenodo1048848, doi105281zenodo16171435, doi105281zenodo3725717, doi105281zenodo4664674, doi105860choice393984, madsen1976a, openalexw1582238871, openalexw2603028126, openalexw2609000594, openalexw337536883, ostrom2019osteology, ostrom2020stratigraphy, sues1978a"
}

A new theropod record from the Marília Formation (Late Cretaceous, Minas Gerais, Brazil) is here described. It consists of an isolated manual ungual which exhibits derived maniraptoran features (e.g., presence of proximodorsal lip). The ungual distinguishes by a set of unique features (e.g., dorsoventrally low and proximodistally elongate profile in side view; block-like flexor tuberosity; proximal articular surface more dorsally oriented than in other theropods; cutting «keel» located distally on ventral surface) suggesting that the animal that produced it was a member of an unknown group of derived maniraptoran theropods, other than alvarezsaurids, deinonychosaurians and oviraptorosaurians already recorded in South America.

@article{doi1022179revmacn7344,
    author = "Novas, Fernando E. and Ribeiro, Luis Borges and de Souza Carvalho, Ismar",
    title = "Maniraptoran theropod ungual from the Marília Formation (Upper Cretaceous), Brazil",
    year = "2005",
    journal = "Revista del Museo Argentino de Ciencias Naturales",
    abstract = "A new theropod record from the Marília Formation (Late Cretaceous, Minas Gerais, Brazil) is here described. It consists of an isolated manual ungual which exhibits derived maniraptoran features (e.g., presence of proximodorsal lip). The ungual distinguishes by a set of unique features (e.g., dorsoventrally low and proximodistally elongate profile in side view; block-like flexor tuberosity; proximal articular surface more dorsally oriented than in other theropods; cutting «keel» located distally on ventral surface) suggesting that the animal that produced it was a member of an unknown group of derived maniraptoran theropods, other than alvarezsaurids, deinonychosaurians and oviraptorosaurians already recorded in South America.",
    url = "https://doi.org/10.22179/revmacn.7.344",
    doi = "10.22179/revmacn.7.344",
    openalex = "W2416328483",
    references = "doi101006cres20000207, doi101038387390a0, doi101038nature03285, doi101139e93187, doi101144gsjgs15310005, doi1015468gbdyof, doi1016710272463420020220460ancroc20co2, doi102307jctvqc6gzx, doi105281zenodo16246150, ostrom2019osteology"
}

Abstract Recent fieldwork in the Upper Cretaceous (Maastrichtian) Maevarano Formation, northwest Madagascar, has yielded important new skull material of the abelisaurid theropod, Majungasaurus crenatissimus. One of these specimens in particular—a virtually complete, disarticulated, and well preserved skull—greatly elucidates the craniofacial osteology of abelisaurids. Herein we describe the skull and lower jaws of this mid-sized theropod dinosaur. A number of features of the facial skeleton and cranium (as well as the postcranium) appear to result from increased levels of mineralization and ossification, which, at least in some instances, can be related directly to specific soft-tissue structures; examples include lacrimal-postorbital contact dorsal to the orbit, suborbital processes of the lacrimal and postorbital, presence of a mineralized interorbital septum, fused interdental plates, and mineralization of the overlying integument. Autapomorphic features include a highly derived nasal—greatly thickened and fused to its counterpart, with a large interior pneumatic chamber—and a median, ‘dome’-like thickening of the frontals, which appear to have been variably pneumatized by a paranasal air sac. Majungasaurus also possesses a derived suite of skull morphologies, including: a rostrocaudally abbreviated, dorsoventrally deep, and transversely broad skull; an expanded occiput, likely associated with expanded cervical musculature; short-crowned dentition; and an enlarged external mandibular fenestra consistent with a moderate degree of intramandibular movement or accommodation. A number of characters, present on both the skull and postcranial skeleton, suggest a divergent mode of predation relative to other, non-abelisaurid theropods. MALAGASY ABSTRACT (FAMINTINANA)—Ireo asa fikarohana natao tao amin'ny Fiforonanana Maevarano tamin'ny vanim-potoana Cretaceous Ambony (Maastrichtian) tany amin'ny faritra avaratr'andrefan'i Madagasikara dia nahitana taolan-karan-doha vaovao tena sarobidy tokoa izay an'ny abelisaurid theropod, Majungasaurus crenatissimus. Iray tamin'ireo taolana ireo dia nisongadina satria saika feno tanteraka na tsy nitambatra tsara intsony aza dia tena voatahiry tsara io taolan-doha io, ka nahahana nampiseho mazava tsara ny fiforonan'ny taolan'ny loha sy ny tavan'ny abelisaurids. Koa eto izahay dia manazava ny taolan-doha sy ny valan-dranon'ny theropod dia ireo theropod dinozaoro izay manana vatana tsy lehibe nefa tsy kely koa. Maro amin'ireo toetran'ny taolan'ny endrika sy ny loha (sy ny aorinan'ny loha) dia ohatry ny vokatry ny fitombon'ny fivontoan'ny mineraly sy ny taolana, izay, farafahakeliny ho an'reo karazany sasany, dia azo heverina ho misy fifandraisany amin'ny firafitr'ireo rakotra malefaka miavaka; ohatra ny fifandraisan'ny lacrimal-postorbital aoriana amin'ny lavaky ny maso, ny vohitry ny suborbital-n'ny lacrimal sy ny postorbital, ny fisian'ny fvontosan'ny mineraly interorbital septum, fitambaran'ny taolam-pisaka manelana ny nify, ary fivontosan'ny mineraly tegument anatiny mipetraka ambony. Ireo toetra autapomorphic dia ahitana ireo taolan'orona nisy fivoarana be, izay manome endrika matevina sy mitambatra amin'ny lafiny mifanila aminy, ka ny endrika anatiny dia malalaka afaka hitoeran'ny rivotra, sy mitondra vohitra afovoany toa mampitombo ny fahatevenan'ny taolan'andrina, izay toa milaza fa toa afaka nitoeran'ny rivotra noho ny paranasal izay kitapon-drivotra. Majungasaurus koa dia manana endriky ny fivoaran'ny karan-doha, ka anisan'izany ny fihenan'ny rostro aoriana, lalina ny faritra afovoany-aoriana, sy mivelatra ny sisin'ny karan-doha, mivelatra ny occiput, izay mampiseho ny toetra mafonja ny hozatry ny loha; boribory-fohy ny nify; ary mivelatra ny mandibular fenestra ivelany mifanaraka amin'ny fahafahan'ny fihetsehana na fandraisana ihany koa ny intramandibular. Maro amin'ireo toetra hita amin'ny karan-doha sy ny taolan'ny vatana dia afahana mamantatra ireo karazana fomba fihazana raha ampitahaina amin'ieo hafa dia ireo tsy abelisaurid theropods.

@article{doi1016710272463420072732caomct20co2,
    author = "Sampson, Scott D. and Witmer, Lawrence M.",
    title = "CRANIOFACIAL ANATOMY OF MAJUNGASAURUS CRENATISSIMUS (THEROPODA: ABELISAURIDAE) FROM THE LATE CRETACEOUS OF MADAGASCAR",
    year = "2007",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "Abstract Recent fieldwork in the Upper Cretaceous (Maastrichtian) Maevarano Formation, northwest Madagascar, has yielded important new skull material of the abelisaurid theropod, Majungasaurus crenatissimus. One of these specimens in particular—a virtually complete, disarticulated, and well preserved skull—greatly elucidates the craniofacial osteology of abelisaurids. Herein we describe the skull and lower jaws of this mid-sized theropod dinosaur. A number of features of the facial skeleton and cranium (as well as the postcranium) appear to result from increased levels of mineralization and ossification, which, at least in some instances, can be related directly to specific soft-tissue structures; examples include lacrimal-postorbital contact dorsal to the orbit, suborbital processes of the lacrimal and postorbital, presence of a mineralized interorbital septum, fused interdental plates, and mineralization of the overlying integument. Autapomorphic features include a highly derived nasal—greatly thickened and fused to its counterpart, with a large interior pneumatic chamber—and a median, ‘dome’-like thickening of the frontals, which appear to have been variably pneumatized by a paranasal air sac. Majungasaurus also possesses a derived suite of skull morphologies, including: a rostrocaudally abbreviated, dorsoventrally deep, and transversely broad skull; an expanded occiput, likely associated with expanded cervical musculature; short-crowned dentition; and an enlarged external mandibular fenestra consistent with a moderate degree of intramandibular movement or accommodation. A number of characters, present on both the skull and postcranial skeleton, suggest a divergent mode of predation relative to other, non-abelisaurid theropods. MALAGASY ABSTRACT (FAMINTINANA)—Ireo asa fikarohana natao tao amin'ny Fiforonanana Maevarano tamin'ny vanim-potoana Cretaceous Ambony (Maastrichtian) tany amin'ny faritra avaratr'andrefan'i Madagasikara dia nahitana taolan-karan-doha vaovao tena sarobidy tokoa izay an'ny abelisaurid theropod, Majungasaurus crenatissimus. Iray tamin'ireo taolana ireo dia nisongadina satria saika feno tanteraka na tsy nitambatra tsara intsony aza dia tena voatahiry tsara io taolan-doha io, ka nahahana nampiseho mazava tsara ny fiforonan'ny taolan'ny loha sy ny tavan'ny abelisaurids. Koa eto izahay dia manazava ny taolan-doha sy ny valan-dranon'ny theropod dia ireo theropod dinozaoro izay manana vatana tsy lehibe nefa tsy kely koa. Maro amin'ireo toetran'ny taolan'ny endrika sy ny loha (sy ny aorinan'ny loha) dia ohatry ny vokatry ny fitombon'ny fivontoan'ny mineraly sy ny taolana, izay, farafahakeliny ho an'reo karazany sasany, dia azo heverina ho misy fifandraisany amin'ny firafitr'ireo rakotra malefaka miavaka; ohatra ny fifandraisan'ny lacrimal-postorbital aoriana amin'ny lavaky ny maso, ny vohitry ny suborbital-n'ny lacrimal sy ny postorbital, ny fisian'ny fvontosan'ny mineraly interorbital septum, fitambaran'ny taolam-pisaka manelana ny nify, ary fivontosan'ny mineraly tegument anatiny mipetraka ambony. Ireo toetra autapomorphic dia ahitana ireo taolan'orona nisy fivoarana be, izay manome endrika matevina sy mitambatra amin'ny lafiny mifanila aminy, ka ny endrika anatiny dia malalaka afaka hitoeran'ny rivotra, sy mitondra vohitra afovoany toa mampitombo ny fahatevenan'ny taolan'andrina, izay toa milaza fa toa afaka nitoeran'ny rivotra noho ny paranasal izay kitapon-drivotra. Majungasaurus koa dia manana endriky ny fivoaran'ny karan-doha, ka anisan'izany ny fihenan'ny rostro aoriana, lalina ny faritra afovoany-aoriana, sy mivelatra ny sisin'ny karan-doha, mivelatra ny occiput, izay mampiseho ny toetra mafonja ny hozatry ny loha; boribory-fohy ny nify; ary mivelatra ny mandibular fenestra ivelany mifanaraka amin'ny fahafahan'ny fihetsehana na fandraisana ihany koa ny intramandibular. Maro amin'ireo toetra hita amin'ny karan-doha sy ny taolan'ny vatana dia afahana mamantatra ireo karazana fomba fihazana raha ampitahaina amin'ieo hafa dia ireo tsy abelisaurid theropods.",
    url = "https://doi.org/10.1671/0272-4634(2007)27[32:caomct]2.0.co;2",
    doi = "10.1671/0272-4634(2007)27[32:caomct]2.0.co;2",
    openalex = "W2014255071",
    references = "carr1999craniofacial, doi10100797814684392981, doi101007978148995740520, doi101017s0094837300011891, doi101017s0094837300012331, doi101029sc005p0175, doi101038063003a0, doi101038142004a0, doi101038172240b0, doi10103835059070, doi101038nature02048, doi10108002724634199510011250, doi10108002724634199710011027, doi10108002724634199910011161, doi10108002724634200310010947, doi101098rspb20042692, doi101098rstb19610007, doi101098rstb19830079, doi101098rstb19910056, doi101111j109636421997tb00340x, doi101111j146979981985tb04915x, doi101126science28454232137, doi101139e93179, doi1015468gbdyof, doi1016710272463420020220460ancroc20co2, doi1016710272463420020220510toomka20co2, doi10167102724634200727127tpasom20co2, doi1023071292217, doi1023072407154, doi1023073889334, doi105281zenodo16171435, doi105281zenodo3725717, doi105281zenodo4664674, doi105479si03629236110i, doi105860choice353642, doi105860choice421568, doi105860choice434677, doi105962bhltitle82144, doi105962p226819, madsen1976a, openalexw2527820321, openalexw2603028126, openalexw3114518543, openalexw575222456"
}

@article{doi101007s0011400804874,
    author = "Canale, Juan I. and Scanferla, Agustín and Agnolín, Federico L. and Novas, Fernando E.",
    title = "New carnivorous dinosaur from the Late Cretaceous of NW Patagonia and the evolution of abelisaurid theropods",
    year = "2008",
    journal = "Die Naturwissenschaften",
    url = "https://doi.org/10.1007/s00114-008-0487-4",
    doi = "10.1007/s00114-008-0487-4",
    openalex = "W1974742710",
    references = "doi1016710272463420020220460ancroc20co2, doi10167102724634200727127tpasom20co2, doi1016710272463420072732caomct20co2, doi1022179revmacn688, doi105281zenodo5376792"
}

The observed diversity of dinosaurs reached its highest peak during the mid- and Late Cretaceous, the 50 Myr that preceded their extinction, and yet this explosion of dinosaur diversity may be explained largely by sampling bias. It has long been debated whether dinosaurs were part of the Cretaceous Terrestrial Revolution (KTR), from 125-80 Myr ago, when flowering plants, herbivorous and social insects, squamates, birds and mammals all underwent a rapid expansion. Although an apparent explosion of dinosaur diversity occurred in the mid-Cretaceous, coinciding with the emergence of new groups (e.g. neoceratopsians, ankylosaurid ankylosaurs, hadrosaurids and pachycephalosaurs), results from the first quantitative study of diversification applied to a new supertree of dinosaurs show that this apparent burst in dinosaurian diversity in the last 18 Myr of the Cretaceous is a sampling artefact. Indeed, major diversification shifts occurred largely in the first one-third of the group's history. Despite the appearance of new clades of medium to large herbivores and carnivores later in dinosaur history, these new originations do not correspond to significant diversification shifts. Instead, the overall geometry of the Cretaceous part of the dinosaur tree does not depart from the null hypothesis of an equal rates model of lineage branching. Furthermore, we conclude that dinosaurs did not experience a progressive decline at the end of the Cretaceous, nor was their evolution driven directly by the KTR.

@article{doi101098rspb20080715,
    author = "Lloyd, Graeme T. and Davis, Katie E. and Pisani, Davide and Tarver, James E. and Ruta, Marcello and Sakamoto, Manabu and Hone, David W. E. and Jennings, Rachel and Benton, Michael J.",
    title = "Dinosaurs and the Cretaceous Terrestrial Revolution",
    year = "2008",
    journal = "Proceedings of the Royal Society B Biological Sciences",
    abstract = "The observed diversity of dinosaurs reached its highest peak during the mid- and Late Cretaceous, the 50 Myr that preceded their extinction, and yet this explosion of dinosaur diversity may be explained largely by sampling bias. It has long been debated whether dinosaurs were part of the Cretaceous Terrestrial Revolution (KTR), from 125-80 Myr ago, when flowering plants, herbivorous and social insects, squamates, birds and mammals all underwent a rapid expansion. Although an apparent explosion of dinosaur diversity occurred in the mid-Cretaceous, coinciding with the emergence of new groups (e.g. neoceratopsians, ankylosaurid ankylosaurs, hadrosaurids and pachycephalosaurs), results from the first quantitative study of diversification applied to a new supertree of dinosaurs show that this apparent burst in dinosaurian diversity in the last 18 Myr of the Cretaceous is a sampling artefact. Indeed, major diversification shifts occurred largely in the first one-third of the group's history. Despite the appearance of new clades of medium to large herbivores and carnivores later in dinosaur history, these new originations do not correspond to significant diversification shifts. Instead, the overall geometry of the Cretaceous part of the dinosaur tree does not depart from the null hypothesis of an equal rates model of lineage branching. Furthermore, we conclude that dinosaurs did not experience a progressive decline at the end of the Cretaceous, nor was their evolution driven directly by the KTR.",
    url = "https://doi.org/10.1098/rspb.2008.0715",
    doi = "10.1098/rspb.2008.0715",
    openalex = "W2131872692",
    references = "doi101007978140206754912413, doi101017cbo9780511536045, doi101038274661a0, doi101038nature05634, doi101046j14610248200100230x, doi101073pnas0606028103, doi101073pnas111144698, doi101093bioinformatics124357, doi101111j109600311999tb00277x, doi101126science1118806, doi101126science1144066, doi101159000452856, doi1015159780691224244, doi101525california97805202420980010001, doi101525california97805202462320010001, openalexw2989049194, openalexw3217097258, sloan1986gradual, smith2007marine"
}

Fossils of a predatory dinosaur provide novel information about the evolution of unenlagiines, a poorly known group of dromaeosaurid theropods from Gondwana. The new dinosaur is the largest dromaeosaurid yet discovered in the Southern Hemisphere and depicts bizarre cranial and postcranial features. Its long and low snout bears numerous, small-sized conical teeth, a condition resembling spinosaurid theropods. Its short forearms depart from the characteristically long-armed condition of all dromaeosaurids and their close avian relatives. The new discovery amplifies the range of morphological disparity among unenlagiines, demonstrating that by the end of the Cretaceous this clade included large, short-armed forms alongside crow-sized, long-armed, possibly flying representatives. The new dinosaur is the youngest record of dromaeosaurids from Gondwana and represents a previously unrecognized lineage of large predators in Late Cretaceous dinosaur faunas mainly dominated by abelisaurid theropods.

@article{doi101098rspb20081554,
    author = "Novas, Fernando E. and Pol, Diego and Canale, Juan I. and Porfiri, Juan D. and Calvo, Jorge O.",
    title = "A bizarre Cretaceous theropod dinosaur from Patagonia and the evolution of Gondwanan dromaeosaurids",
    year = "2008",
    journal = "Proceedings of the Royal Society B Biological Sciences",
    abstract = "Fossils of a predatory dinosaur provide novel information about the evolution of unenlagiines, a poorly known group of dromaeosaurid theropods from Gondwana. The new dinosaur is the largest dromaeosaurid yet discovered in the Southern Hemisphere and depicts bizarre cranial and postcranial features. Its long and low snout bears numerous, small-sized conical teeth, a condition resembling spinosaurid theropods. Its short forearms depart from the characteristically long-armed condition of all dromaeosaurids and their close avian relatives. The new discovery amplifies the range of morphological disparity among unenlagiines, demonstrating that by the end of the Cretaceous this clade included large, short-armed forms alongside crow-sized, long-armed, possibly flying representatives. The new dinosaur is the youngest record of dromaeosaurids from Gondwana and represents a previously unrecognized lineage of large predators in Late Cretaceous dinosaur faunas mainly dominated by abelisaurid theropods.",
    url = "https://doi.org/10.1098/rspb.2008.1554",
    doi = "10.1098/rspb.2008.1554",
    openalex = "W2065351263",
    references = "doi101038nature03285, doi1022179revmacn688, doi102307jctvqc6gzx, doi105860choice434677, openalexw834136096"
}

Abstract: A new Late Cretaceous titanosaur sauropod from the Bauru Basin of Brazil, Uberabatitan ribeiroi gen. et sp. nov., represented by at least three specimens, is described. The material comes from a level of coarse sandstone within the Serra da Galga sequence in Uberaba County, Minas Gerais State. The fossiliferous strata belong to the Marília Formation (Serra da Galga Member), Bauru Group, considered to be Maastrichtian in age. The fossils occur in the uppermost levels of the above‐mentioned unit; thus, Uberabatitan ribeiroi is the youngest titanosaur to have been recorded from the Bauru Basin. The autapomorphies that support the new species are: (1) anterior and mid‐cervicals with postzygodiapophyseal lamina (podl) segmented in zygapophyseal and diapophyseal laminae, of which the first extends rostrodorsally over the second; (2) mid‐dorsals with a robust lateral lamina formed mainly by a diapophyseal lamina (probably homologous to the postzygodiapophyseal lamina), and, to a lesser extent, by a relic of the spinodiapophyseal lamina (spdl); (3) mid (and probably posterior) dorsals with accessory neural laminae, which are lateral to the prespinal lamina, and probably homologous to the spinoprezygapophyseal laminae (sprl); (4) mid‐caudal centra with deeply excavated lateral faces; (5) pubis very thick and robust, with a very stout longitudinal crest on its external (ventral) face; and (6) proximal end of the tibia with a prominent lateral protuberance, which articulates with an equally prominent medial knob of the fibula. The titanosaurian assemblage at Uberaba includes, apart from U. ribeiroi, well‐preserved specimens assigned to species of uncertain affinities (Trigonosaurus pricei and Baurutitan britoi), as well as a few vertebrae assigned to aeolosaurines.

@article{doi101111j14754983200800781x,
    author = "Salgado, Leonardo and de Souza Carvalho, Ismar",
    title = "UBERABATITAN RIBEIROI, A NEW TITANOSAUR FROM THE MARÍLIA FORMATION (BAURU GROUP, UPPER CRETACEOUS), MINAS GERAIS, BRAZIL",
    year = "2008",
    journal = "Palaeontology",
    abstract = "Abstract: A new Late Cretaceous titanosaur sauropod from the Bauru Basin of Brazil, Uberabatitan ribeiroi gen. et sp. nov., represented by at least three specimens, is described. The material comes from a level of coarse sandstone within the Serra da Galga sequence in Uberaba County, Minas Gerais State. The fossiliferous strata belong to the Marília Formation (Serra da Galga Member), Bauru Group, considered to be Maastrichtian in age. The fossils occur in the uppermost levels of the above‐mentioned unit; thus, Uberabatitan ribeiroi is the youngest titanosaur to have been recorded from the Bauru Basin. The autapomorphies that support the new species are: (1) anterior and mid‐cervicals with postzygodiapophyseal lamina (podl) segmented in zygapophyseal and diapophyseal laminae, of which the first extends rostrodorsally over the second; (2) mid‐dorsals with a robust lateral lamina formed mainly by a diapophyseal lamina (probably homologous to the postzygodiapophyseal lamina), and, to a lesser extent, by a relic of the spinodiapophyseal lamina (spdl); (3) mid (and probably posterior) dorsals with accessory neural laminae, which are lateral to the prespinal lamina, and probably homologous to the spinoprezygapophyseal laminae (sprl); (4) mid‐caudal centra with deeply excavated lateral faces; (5) pubis very thick and robust, with a very stout longitudinal crest on its external (ventral) face; and (6) proximal end of the tibia with a prominent lateral protuberance, which articulates with an equally prominent medial knob of the fibula. The titanosaurian assemblage at Uberaba includes, apart from U. ribeiroi, well‐preserved specimens assigned to species of uncertain affinities (Trigonosaurus pricei and Baurutitan britoi), as well as a few vertebrae assigned to aeolosaurines.",
    url = "https://doi.org/10.1111/j.1475-4983.2008.00781.x",
    doi = "10.1111/j.1475-4983.2008.00781.x",
    openalex = "W2070197359",
    references = "doi101006cres20000207"
}

We report the discovery of basal abelisaurid and carcharodontosaurid theropods from the mid Cretaceous (Aptian-Albian, ca. 112 Ma) Elrhaz Formation of the Niger Republic. The abelisaurid, Kryptops palaios gen. et sp. nov., is represented by a single individual preserving the maxilla, pelvic girdle, vertebrae and ribs. Several features, including a maxilla textured externally by impressed vascular grooves and a narrow antorbital fossa, clearly place Kryptops palaios within Abelisauridae as its oldest known member. The carcharodontosaurid, Eocarcharia dinops gen. et sp. nov., is represented by several cranial bones and isolated teeth. Phylogenetic analysis places it as a basal carcharodontosaurid, similar to Acrocanthosaurus and less derived than Carcharodontosaurus and Giganotosaurus. The discovery of these taxa suggests that large body size and many of the derived cranial features of abelisaurids and carcharodontosaurids had already evolved by the mid Cretaceous. The presence of a close relative of the North American genus Acrocanthosaurus on Africa suggests that carcharodontosaurids had already achieved a trans-Tethyan distribution by the mid Cretaceous.

@article{doi104202app20080102,
    author = "Sereno, Paul C. and Brusatte, Stephen L.",
    title = "Basal Abelisaurid and Carcharodontosaurid Theropods from the Lower Cretaceous Elrhaz Formation of Niger",
    year = "2008",
    journal = "Acta Palaeontologica Polonica",
    abstract = "We report the discovery of basal abelisaurid and carcharodontosaurid theropods from the mid Cretaceous (Aptian-Albian, ca. 112 Ma) Elrhaz Formation of the Niger Republic. The abelisaurid, Kryptops palaios gen. et sp. nov., is represented by a single individual preserving the maxilla, pelvic girdle, vertebrae and ribs. Several features, including a maxilla textured externally by impressed vascular grooves and a narrow antorbital fossa, clearly place Kryptops palaios within Abelisauridae as its oldest known member. The carcharodontosaurid, Eocarcharia dinops gen. et sp. nov., is represented by several cranial bones and isolated teeth. Phylogenetic analysis places it as a basal carcharodontosaurid, similar to Acrocanthosaurus and less derived than Carcharodontosaurus and Giganotosaurus. The discovery of these taxa suggests that large body size and many of the derived cranial features of abelisaurids and carcharodontosaurids had already evolved by the mid Cretaceous. The presence of a close relative of the North American genus Acrocanthosaurus on Africa suggests that carcharodontosaurids had already achieved a trans-Tethyan distribution by the mid Cretaceous.",
    url = "https://doi.org/10.4202/app.2008.0102",
    doi = "10.4202/app.2008.0102",
    openalex = "W2068353031",
    references = "doi101002ara20206, doi101016004019519190231g, doi101017cbo9780511536045, doi101017s0016756804000330, doi101029jb084ib11p05973, doi10108002724634199710011027, doi101086273307, doi10113008137233291, doi1016710272463420020220460ancroc20co2, doi101671027246342003231apfast20co2, doi10167102724634200727127tpasom20co2, doi1016710272463420072732caomct20co2, doi1034191b109, doi103998mpub9690664, doi105281zenodo16171435, doi105281zenodo4664674, doi105281zenodo5376792, openalexw2173200745, openalexw2989049194"
}

@article{lindgren2008theropod,
    author = "Lindgren, Johan and Currie, Philip J. and Rees, Jan and Siverson, Mikael and Lindström, Sofie and Alwmark, Carl",
    title = "Theropod dinosaur teeth from the lowermost Cretaceous Rabekke Formation on Bornholm, Denmark",
    year = "2008",
    journal = "Geobios",
    url = "https://doi.org/10.1016/j.geobios.2007.05.001",
    doi = "10.1016/j.geobios.2007.05.001",
    number = "2",
    openalex = "W1964932668",
    pages = "253-262",
    volume = "41",
    references = "doi101017cbo9780511608377011, doi101017s247526300000091x, doi10103835047056, doi10103845769, doi101098rspl18870117, doi1023071485834, doi1023072657004, doi105281zenodo16171435, openalexw3013888078, openalexw3215057009"
}

Rauhut, Oliver W. M., Milner, Angela C., Moore-Fay, Scott (2010): Cranial osteology and phylogenetic position of the theropod dinosaur Proceratosaurus bradleyi (Woodward, 1910) from the Middle Jurassic of England. Zoological Journal of the Linnean Society 158 (1): 155-195, DOI: 10.1111/j.1096-3642.2009.00591.x, URL: http://dx.doi.org/10.1111/j.1096-3642.2009.00591.x

@article{doi101111j10963642200900591x,
    author = "Rauhut, Oliver W. M. and Milner, Angela C. and Moore-Fay, Scott",
    title = "Cranial osteology and phylogenetic position of the theropod dinosaur Proceratosaurus bradleyi (Woodward, 1910) from the Middle Jurassic of England",
    year = "2009",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "Rauhut, Oliver W. M., Milner, Angela C., Moore-Fay, Scott (2010): Cranial osteology and phylogenetic position of the theropod dinosaur Proceratosaurus bradleyi (Woodward, 1910) from the Middle Jurassic of England. Zoological Journal of the Linnean Society 158 (1): 155-195, DOI: 10.1111/j.1096-3642.2009.00591.x, URL: http://dx.doi.org/10.1111/j.1096-3642.2009.00591.x",
    url = "https://doi.org/10.1111/j.1096-3642.2009.00591.x",
    doi = "10.1111/j.1096-3642.2009.00591.x",
    openalex = "W2139842739",
    references = "crossref1998encyclopedia, doi101017cbo9780511536045, doi10108025761900202212131807, doi101098rspl18870117, doi101126science28454232137, doi102307jctvqc6gzx, doi102475ajss319111253, doi105860choice331556, openalexw2989049194, openalexw3215057009, openalexw3217097258, openalexw70084438, owen2015monograph, vonhuene1923carnivorous, woodward1910on"
}

We review the morphology, taxonomy, and phylogenetic relationships of the upper Cretaceous Mongolian troodontid Saurornithoides. Saurornithoides mongoliensis is known only by the holotype from Bayan Zag, Djadokhta Formation. This specimen includes a nearly complete, but weathered, skull and mandibles, a series of dorsal, sacral, and caudal vertebrae, and a partial pelvic girdle and hind limb. Saurornithoides junior, here referred to Zanabazar, also is known only by the holotype from Bugiin Tsav, Nemegt Formation. This specimen consists of a skull and partial mandible, a series of sacral and caudal vertebrae, a partial pelvic girdle, and the distal part of the right hind limb. Saurornithoides Zanabazar is one of the few Mongolian taxa known from both the Djadokhta and Nemegt formations. The monophyly of Saurornithoides Zanabazar has not been seriously questioned historically, yet empirical support for this clade is currently tenuous. A privileged phylogenetic relationship between Saurornithoides, Zanabazar, and the North American troodontid Troodon formosus is supported by numerous characters including the presence of a subotic recess, lateroventrally projecting and hollow basipterygoid processes, a lacrimal whose anterior process is significantly longer than its posterior process, a highly pneumatized parasphenoid rostrum, a constricted neck of the occipital condyle, a symphyseal region of the dentary that is slightly recurved medially, and an obturator process located near the middle of the ischiadic shaft. CT data for the skulls of both species facilitated a description of the endocranial anatomy of Saurornithoides mongoliensis and Zanabazar junior, including a reconstruction of the endocranial space of Zanabazar junior. Despite being the largest of the known troodontid species, the endocranial volume of Zanabazar junior is considerably smaller than that estimated for Troodon formosus, suggesting that the extremely high encephalization quotient of Troodon formosus may be autapomorphic among troodontids.

@article{doi1012066481,
    author = "Norell, Mark A. and Makovicky, Peter J. and Bever, Gabe S. and Balanoff, Amy M. and Clark, James M. and Барсболд, Ринчен and Rowe, Timothy",
    title = "A Review of the Mongolian Cretaceous Dinosaur Saurornithoides (Troodontidae: Theropoda)",
    year = "2009",
    journal = "American Museum Novitates",
    abstract = "We review the morphology, taxonomy, and phylogenetic relationships of the upper Cretaceous Mongolian troodontid Saurornithoides. Saurornithoides mongoliensis is known only by the holotype from Bayan Zag, Djadokhta Formation. This specimen includes a nearly complete, but weathered, skull and mandibles, a series of dorsal, sacral, and caudal vertebrae, and a partial pelvic girdle and hind limb. Saurornithoides junior, here referred to Zanabazar, also is known only by the holotype from Bugiin Tsav, Nemegt Formation. This specimen consists of a skull and partial mandible, a series of sacral and caudal vertebrae, a partial pelvic girdle, and the distal part of the right hind limb. Saurornithoides Zanabazar is one of the few Mongolian taxa known from both the Djadokhta and Nemegt formations. The monophyly of Saurornithoides Zanabazar has not been seriously questioned historically, yet empirical support for this clade is currently tenuous. A privileged phylogenetic relationship between Saurornithoides, Zanabazar, and the North American troodontid Troodon formosus is supported by numerous characters including the presence of a subotic recess, lateroventrally projecting and hollow basipterygoid processes, a lacrimal whose anterior process is significantly longer than its posterior process, a highly pneumatized parasphenoid rostrum, a constricted neck of the occipital condyle, a symphyseal region of the dentary that is slightly recurved medially, and an obturator process located near the middle of the ischiadic shaft. CT data for the skulls of both species facilitated a description of the endocranial anatomy of Saurornithoides mongoliensis and Zanabazar junior, including a reconstruction of the endocranial space of Zanabazar junior. Despite being the largest of the known troodontid species, the endocranial volume of Zanabazar junior is considerably smaller than that estimated for Troodon formosus, suggesting that the extremely high encephalization quotient of Troodon formosus may be autapomorphic among troodontids.",
    url = "https://doi.org/10.1206/648.1",
    doi = "10.1206/648.1",
    openalex = "W1995173965",
    references = "doi1010160195667191900155, doi101038415780a, doi101038nature02706, doi101038nature02898, doi101038nature03285, doi101038nature03996, doi101086273307, doi101126science1144066, doi101126science27953581915, doi10120600030082200635451andtfu20co2, doi105281zenodo16171435, openalexw2607033038, openalexw834136096, russell1969a"
}

Interpreting key ecological parameters, such as diet, of extinct organisms without the benefit of direct observation or explicit fossil evidence poses a formidable challenge for paleobiological studies. To date, dietary categorizations of extinct taxa are largely generated by means of modern analogs; however, for many species the method is subject to considerable ambiguity. Here we present a refined approach for assessing trophic habits in fossil taxa and apply the method to coelurosaurian dinosaurs--a clade for which diet is particularly controversial. Our findings detect 21 morphological features that exhibit statistically significant correlations with extrinsic fossil evidence of coelurosaurian herbivory, such as stomach contents and a gastric mill. These traits represent quantitative, extrinsically founded proxies for identifying herbivorous ecomorphology in fossils and are robust despite uncertainty in phylogenetic relationships among major coelurosaurian subclades. The distribution of these features suggests that herbivory was widespread among coelurosaurians, with six major subclades displaying morphological evidence of the diet, and that contrary to previous thought, hypercarnivory was relatively rare and potentially secondarily derived. Given the potential for repeated, independent evolution of herbivory in Coelurosauria, we also test for repetitive patterns in the appearance of herbivorous traits within sublineages using rank concordance analysis. We find evidence for a common succession of increasing specialization to herbivory in the subclades Ornithomimosauria and Oviraptorosauria, perhaps underlain by intrinsic functional and/or developmental constraints, as well as evidence indicating that the early evolution of a beak in coelurosaurians correlates with an herbivorous diet.

@article{doi101073pnas1011924108,
    author = "Zanno, Lindsay E. and Makovicky, Peter J.",
    title = "Herbivorous ecomorphology and specialization patterns in theropod dinosaur evolution",
    year = "2010",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = "Interpreting key ecological parameters, such as diet, of extinct organisms without the benefit of direct observation or explicit fossil evidence poses a formidable challenge for paleobiological studies. To date, dietary categorizations of extinct taxa are largely generated by means of modern analogs; however, for many species the method is subject to considerable ambiguity. Here we present a refined approach for assessing trophic habits in fossil taxa and apply the method to coelurosaurian dinosaurs--a clade for which diet is particularly controversial. Our findings detect 21 morphological features that exhibit statistically significant correlations with extrinsic fossil evidence of coelurosaurian herbivory, such as stomach contents and a gastric mill. These traits represent quantitative, extrinsically founded proxies for identifying herbivorous ecomorphology in fossils and are robust despite uncertainty in phylogenetic relationships among major coelurosaurian subclades. The distribution of these features suggests that herbivory was widespread among coelurosaurians, with six major subclades displaying morphological evidence of the diet, and that contrary to previous thought, hypercarnivory was relatively rare and potentially secondarily derived. Given the potential for repeated, independent evolution of herbivory in Coelurosauria, we also test for repetitive patterns in the appearance of herbivorous traits within sublineages using rank concordance analysis. We find evidence for a common succession of increasing specialization to herbivory in the subclades Ornithomimosauria and Oviraptorosauria, perhaps underlain by intrinsic functional and/or developmental constraints, as well as evidence indicating that the early evolution of a beak in coelurosaurians correlates with an herbivorous diet.",
    url = "https://doi.org/10.1073/pnas.1011924108",
    doi = "10.1073/pnas.1011924108",
    openalex = "W2133829099",
    references = "doi10103831635, doi101038nature00930, doi101038nature08322, doi10108008912960600719988, doi101098rspb19940006, doi101111j1469185x201000137x, doi101126science1161833, doi101126science13334591105, doi101139e03011, doi101139e72031, doi101159000156416, doi1023072285423, doi105281zenodo1040385, doi105860choice326223, doi105860choice392183, openalexw2097385721, openalexw2611511275"
}

Sixteen isolated theropod teeth were discovered in two areas in the upper Middle-lower Upper Jurassic Shishugou Formation of the Xinjiang Uyghur Autonomous Region, northwest China. This sample can be divided on the basis of qualitative features and simple quantitative metrics into seven tooth morphotypes, each of which probably represents a distinct taxon. Three of the morphotypes may be attributable to theropods already known from the Shishugou Formation, namely the alvarezsauroid Haplocheirus and the basal tetanurans Monolophosaurus and Sinraptor. The other four morphotypes, however, appear to represent new taxa, taking the known theropod diversity of the Shishugou Formation from six species to at least ten. One of the new taxa is probably a dromaeosaurid. Another appears to represent a troodontid or a relative of the potentially troodontid-like Paronychodon, itself so far known only from isolated teeth. Of the remaining two taxa, one appears to be a basal tetanuran or tyrannosauroid, whereas the other either belongs to one of these same groups or represents a ceratosaur. The probable deinonychosaurian teeth in our sample are among the oldest fossils known for this clade, and highlight the diversity of coelurosaurs in the Shishugou Formation.

@article{doi101080027246342011546291,
    author = "Han, Fenglu and Clark, James M. and Xu, Xing and Sullivan, Corwin and Choiniere, Jonah N. and Hone, David W. E.",
    title = "Theropod teeth from the Middle-Upper Jurassic Shishugou Formation of northwest Xinjiang, China",
    year = "2011",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "Sixteen isolated theropod teeth were discovered in two areas in the upper Middle-lower Upper Jurassic Shishugou Formation of the Xinjiang Uyghur Autonomous Region, northwest China. This sample can be divided on the basis of qualitative features and simple quantitative metrics into seven tooth morphotypes, each of which probably represents a distinct taxon. Three of the morphotypes may be attributable to theropods already known from the Shishugou Formation, namely the alvarezsauroid Haplocheirus and the basal tetanurans Monolophosaurus and Sinraptor. The other four morphotypes, however, appear to represent new taxa, taking the known theropod diversity of the Shishugou Formation from six species to at least ten. One of the new taxa is probably a dromaeosaurid. Another appears to represent a troodontid or a relative of the potentially troodontid-like Paronychodon, itself so far known only from isolated teeth. Of the remaining two taxa, one appears to be a basal tetanuran or tyrannosauroid, whereas the other either belongs to one of these same groups or represents a ceratosaur. The probable deinonychosaurian teeth in our sample are among the oldest fossils known for this clade, and highlight the diversity of coelurosaurs in the Shishugou Formation.",
    url = "https://doi.org/10.1080/02724634.2011.546291",
    doi = "10.1080/02724634.2011.546291",
    openalex = "W1990962634",
    references = "lindgren2008theropod"
}

Pneumatic (air-filled) postcranial bones are unique to birds among extant tetrapods. Unambiguous skeletal correlates of postcranial pneumaticity first appeared in the Late Triassic (approximately 210 million years ago), when they evolved independently in several groups of bird-line archosaurs (ornithodirans). These include the theropod dinosaurs (of which birds are extant representatives), the pterosaurs, and sauropodomorph dinosaurs. Postulated functions of skeletal pneumatisation include weight reduction in large-bodied or flying taxa, and density reduction resulting in energetic savings during foraging and locomotion. However, the influence of these hypotheses on the early evolution of pneumaticity has not been studied in detail previously. We review recent work on the significance of pneumaticity for understanding the biology of extinct ornithodirans, and present detailed new data on the proportion of the skeleton that was pneumatised in 131 non-avian theropods and Archaeopteryx. This includes all taxa known from significant postcranial remains. Pneumaticity of the cervical and anterior dorsal vertebrae occurred early in theropod evolution. This 'common pattern' was conserved on the line leading to birds, and is likely present in Archaeopteryx. Increases in skeletal pneumaticity occurred independently in as many as 12 lineages, highlighting a remarkably high number of parallel acquisitions of a bird-like feature among non-avian theropods. Using a quantitative comparative framework, we show that evolutionary increases in skeletal pneumaticity are significantly concentrated in lineages with large body size, suggesting that mass reduction in response to gravitational constraints at large body sizes influenced the early evolution of pneumaticity. However, the body size threshold for extensive pneumatisation is lower in theropod lineages more closely related to birds (maniraptorans). Thus, relaxation of the relationship between body size and pneumatisation preceded the origin of birds and cannot be explained as an adaptation for flight. We hypothesise that skeletal density modulation in small, non-volant, maniraptorans resulted in energetic savings as part of a multi-system response to increased metabolic demands. Acquisition of extensive postcranial pneumaticity in small-bodied maniraptorans may indicate avian-like high-performance endothermy.

@article{doi101111j1469185x201100190x,
    author = "Benson, Roger and Butler, Richard J. and Carrano, Matthew T. and O’Connor, Patrick M.",
    title = "Air‐filled postcranial bones in theropod dinosaurs: physiological implications and the ‘reptile’–bird transition",
    year = "2011",
    journal = "Biological reviews/Biological reviews of the Cambridge Philosophical Society",
    abstract = "Pneumatic (air-filled) postcranial bones are unique to birds among extant tetrapods. Unambiguous skeletal correlates of postcranial pneumaticity first appeared in the Late Triassic (approximately 210 million years ago), when they evolved independently in several groups of bird-line archosaurs (ornithodirans). These include the theropod dinosaurs (of which birds are extant representatives), the pterosaurs, and sauropodomorph dinosaurs. Postulated functions of skeletal pneumatisation include weight reduction in large-bodied or flying taxa, and density reduction resulting in energetic savings during foraging and locomotion. However, the influence of these hypotheses on the early evolution of pneumaticity has not been studied in detail previously. We review recent work on the significance of pneumaticity for understanding the biology of extinct ornithodirans, and present detailed new data on the proportion of the skeleton that was pneumatised in 131 non-avian theropods and Archaeopteryx. This includes all taxa known from significant postcranial remains. Pneumaticity of the cervical and anterior dorsal vertebrae occurred early in theropod evolution. This 'common pattern' was conserved on the line leading to birds, and is likely present in Archaeopteryx. Increases in skeletal pneumaticity occurred independently in as many as 12 lineages, highlighting a remarkably high number of parallel acquisitions of a bird-like feature among non-avian theropods. Using a quantitative comparative framework, we show that evolutionary increases in skeletal pneumaticity are significantly concentrated in lineages with large body size, suggesting that mass reduction in response to gravitational constraints at large body sizes influenced the early evolution of pneumaticity. However, the body size threshold for extensive pneumatisation is lower in theropod lineages more closely related to birds (maniraptorans). Thus, relaxation of the relationship between body size and pneumatisation preceded the origin of birds and cannot be explained as an adaptation for flight. We hypothesise that skeletal density modulation in small, non-volant, maniraptorans resulted in energetic savings as part of a multi-system response to increased metabolic demands. Acquisition of extensive postcranial pneumaticity in small-bodied maniraptorans may indicate avian-like high-performance endothermy.",
    url = "https://doi.org/10.1111/j.1469-185x.2011.00190.x",
    doi = "10.1111/j.1469-185x.2011.00190.x",
    openalex = "W2003924744",
    references = "doi101002jez513, doi101002jmor10470, doi101002sici1097018520000215261125aidar630co27, doi101007s0011400804883, doi101007s001140090614x, doi101017s0094837300021308, doi101038nature07856, doi101073pnas0708903105, doi10108002724634199710011018, doi101086284325, doi101093auk12041206, doi101093bioinformaticsbtg412, doi101093sysbio41118, doi101098rstb19890106, doi101111j10963642200600245x, doi101111j10963642200900569x, doi101126science1180219, doi1012066481, doi101371journalpone0003303, doi101371journalpone0007390, doi10167102724634200727127tpasom20co2, doi1023071292217, doi1023071441916, doi105281zenodo16171435, doi105860choice392183, doi105860choice434677, doi105962bhltitle60562, openalexw2611511275, openalexw3086315876, ostrom2019osteology, owen1857monograph, owen2015monograph"
}

BACKGROUND: Troodontids are a predominantly small-bodied group of feathered theropod dinosaurs notable for their close evolutionary relationship with Avialae. Despite a diverse Asian representation with remarkable growth in recent years, the North American record of the clade remains poor, with only one controversial species--Troodon formosus--presently known from substantial skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a gracile new troodontid theropod--Talos sampsoni gen. et sp. nov.--from the Upper Cretaceous Kaiparowits Formation, Utah, USA, representing one of the most complete troodontid skeletons described from North America to date. Histological assessment of the holotype specimen indicates that the adult body size of Talos was notably smaller than that of the contemporary genus Troodon. Phylogenetic analysis recovers Talos as a member of a derived, latest Cretaceous subclade, minimally containing Troodon, Saurornithoides, and Zanabazar. MicroCT scans reveal extreme pathological remodeling on pedal phalanx II-1 of the holotype specimen likely resulting from physical trauma and subsequent infectious processes. CONCLUSION/SIGNIFICANCE: Talos sampsoni adds to the singularity of the Kaiparowits Formation dinosaur fauna, which is represented by at least 10 previously unrecognized species including the recently named ceratopsids Utahceratops and Kosmoceratops, the hadrosaurine Gryposaurus monumentensis, the tyrannosaurid Teratophoneus, and the oviraptorosaurian Hagryphus. The presence of a distinct troodontid taxon in the Kaiparowits Formation supports the hypothesis that late Campanian dinosaurs of the Western Interior Basin exhibited restricted geographic ranges and suggests that the taxonomic diversity of Late Cretaceous troodontids from North America is currently underestimated. An apparent traumatic injury to the foot of Talos with evidence of subsequent healing sheds new light on the paleobiology of deinonychosaurians by bolstering functional interpretations of prey grappling and/or intraspecific combat for the second pedal digit, and supporting trackway evidence indicating a minimal role in weight bearing.

@article{doi101371journalpone0024487,
    author = "Zanno, Lindsay E. and Varricchio, David J. and O’Connor, Patrick M. and Titus, Alan L. and Knell, Michael J.",
    title = "A New Troodontid Theropod, Talos sampsoni gen. et sp. nov., from the Upper Cretaceous Western Interior Basin of North America",
    year = "2011",
    journal = "PLoS ONE",
    abstract = "BACKGROUND: Troodontids are a predominantly small-bodied group of feathered theropod dinosaurs notable for their close evolutionary relationship with Avialae. Despite a diverse Asian representation with remarkable growth in recent years, the North American record of the clade remains poor, with only one controversial species--Troodon formosus--presently known from substantial skeletal remains. METHODOLOGY/PRINCIPAL FINDINGS: Here we report a gracile new troodontid theropod--Talos sampsoni gen. et sp. nov.--from the Upper Cretaceous Kaiparowits Formation, Utah, USA, representing one of the most complete troodontid skeletons described from North America to date. Histological assessment of the holotype specimen indicates that the adult body size of Talos was notably smaller than that of the contemporary genus Troodon. Phylogenetic analysis recovers Talos as a member of a derived, latest Cretaceous subclade, minimally containing Troodon, Saurornithoides, and Zanabazar. MicroCT scans reveal extreme pathological remodeling on pedal phalanx II-1 of the holotype specimen likely resulting from physical trauma and subsequent infectious processes. CONCLUSION/SIGNIFICANCE: Talos sampsoni adds to the singularity of the Kaiparowits Formation dinosaur fauna, which is represented by at least 10 previously unrecognized species including the recently named ceratopsids Utahceratops and Kosmoceratops, the hadrosaurine Gryposaurus monumentensis, the tyrannosaurid Teratophoneus, and the oviraptorosaurian Hagryphus. The presence of a distinct troodontid taxon in the Kaiparowits Formation supports the hypothesis that late Campanian dinosaurs of the Western Interior Basin exhibited restricted geographic ranges and suggests that the taxonomic diversity of Late Cretaceous troodontids from North America is currently underestimated. An apparent traumatic injury to the foot of Talos with evidence of subsequent healing sheds new light on the paleobiology of deinonychosaurians by bolstering functional interpretations of prey grappling and/or intraspecific combat for the second pedal digit, and supporting trackway evidence indicating a minimal role in weight bearing.",
    url = "https://doi.org/10.1371/journal.pone.0024487",
    doi = "10.1371/journal.pone.0024487",
    openalex = "W2075731101",
    references = "doi101002ar20986, doi101002sici109686441999081094563aidajpa1130co2x, doi101016jsedgeo200610001, doi101016s0006320796900622, doi101016s0748300703000604, doi101111j155856461985tb00420x, doi1012066481, doi101371journalpone0012292, doi101371journalpone0014329, doi1015468gcrned, doi1016710272463420050250897anotmf20co2, doi1023072408678, doi102307jctvqc6gzx, doi102475ajss319111253, doi105860choice362492, doi105962bhltitle115853, doi105962p339375, openalexw2611511275, openalexw3206657856, openalexw3215057009, wilson1985stenonychosaurus"
}

Most non-avian theropod dinosaurs are characterized by fearsome serrated teeth and sharp recurved claws. Interpretation of theropod predatory ecology is typically based on functional morphological analysis of these and other physical features. The notorious hypertrophied 'killing claw' on pedal digit (D) II of the maniraptoran theropod Deinonychus (Paraves: Dromaeosauridae) is hypothesized to have been a predatory adaptation for slashing or climbing, leading to the suggestion that Deinonychus and other dromaeosaurids were cursorial predators specialized for actively attacking and killing prey several times larger than themselves. However, this hypothesis is problematic as extant animals that possess similarly hypertrophied claws do not use them to slash or climb up prey. Here we offer an alternative interpretation: that the hypertrophied D-II claw of dromaeosaurids was functionally analogous to the enlarged talon also found on D-II of extant Accipitridae (hawks and eagles; one family of the birds commonly known as "raptors"). Here, the talon is used to maintain grip on prey of subequal body size to the predator, while the victim is pinned down by the body weight of the raptor and dismembered by the beak. The foot of Deinonychus exhibits morphology consistent with a grasping function, supportive of the prey immobilisation behavior model. Opposite morphological trends within Deinonychosauria (Dromaeosauridae + Troodontidae) are indicative of ecological separation. Placed in context of avian evolution, the grasping foot of Deinonychus and other terrestrial predatory paravians is hypothesized to have been an exaptation for the grasping foot of arboreal perching birds. Here we also describe "stability flapping", a novel behaviour executed for positioning and stability during the initial stages of prey immobilisation, which may have been pivotal to the evolution of the flapping stroke. These findings overhaul our perception of predatory dinosaurs and highlight the role of exaptation in the evolution of novel structures and behaviours.

@article{doi101371journalpone0028964,
    author = "Fowler, Denver W. and Freedman, Elizabeth A. and Scannella, John B. and Kambic, Robert E.",
    title = "The Predatory Ecology of Deinonychus and the Origin of Flapping in Birds",
    year = "2011",
    journal = "PLoS ONE",
    abstract = {Most non-avian theropod dinosaurs are characterized by fearsome serrated teeth and sharp recurved claws. Interpretation of theropod predatory ecology is typically based on functional morphological analysis of these and other physical features. The notorious hypertrophied 'killing claw' on pedal digit (D) II of the maniraptoran theropod Deinonychus (Paraves: Dromaeosauridae) is hypothesized to have been a predatory adaptation for slashing or climbing, leading to the suggestion that Deinonychus and other dromaeosaurids were cursorial predators specialized for actively attacking and killing prey several times larger than themselves. However, this hypothesis is problematic as extant animals that possess similarly hypertrophied claws do not use them to slash or climb up prey. Here we offer an alternative interpretation: that the hypertrophied D-II claw of dromaeosaurids was functionally analogous to the enlarged talon also found on D-II of extant Accipitridae (hawks and eagles; one family of the birds commonly known as "raptors"). Here, the talon is used to maintain grip on prey of subequal body size to the predator, while the victim is pinned down by the body weight of the raptor and dismembered by the beak. The foot of Deinonychus exhibits morphology consistent with a grasping function, supportive of the prey immobilisation behavior model. Opposite morphological trends within Deinonychosauria (Dromaeosauridae + Troodontidae) are indicative of ecological separation. Placed in context of avian evolution, the grasping foot of Deinonychus and other terrestrial predatory paravians is hypothesized to have been an exaptation for the grasping foot of arboreal perching birds. Here we also describe "stability flapping", a novel behaviour executed for positioning and stability during the initial stages of prey immobilisation, which may have been pivotal to the evolution of the flapping stroke. These findings overhaul our perception of predatory dinosaurs and highlight the role of exaptation in the evolution of novel structures and behaviours.},
    url = "https://doi.org/10.1371/journal.pone.0028964",
    doi = "10.1371/journal.pone.0028964",
    openalex = "W2059526119",
    references = "carpenter2005the, crossref1976allosaurus, doi101002ar20986, doi101007s0011400804883, doi101017cbo9780511608377011, doi10103831635, doi10103835047056, doi10103845769, doi10108002724634198710011651, doi10108010618600199610474713, doi101126science1144066, doi101126science27953581915, doi101666040141, doi1023071390807, doi102307jctvqc6gzx, russell1969a, wilson1985stenonychosaurus"
}

The Late Cretaceous tyrannosaurid theropod Alioramus has long been one of the most puzzling large carnivorous dinosaur taxa, largely because for several decades it has been represented only by a single, fragmentary specimen that seems to represent a long-snouted and gracile individual but is difficult to interpret. The discovery of a substantially complete skeleton of Alioramus at the Tsaagan Khuushu locality in the Maastrichtian Nemegt Formation of Mongolia, recovered during the 2001 American Museum–Mongolian Academy of Sciences expedition and described as a new species (Alioramus altai) in 2009, definitively shows that this mysterious taxon is a distinct form of longirostrine tyrannosaurid that lived alongside the larger and more robust Tarbosaurus. Here we describe and figure this remarkably preserved skeleton in detail. We provide exhaustive descriptions and photographs of individual bones, and make extensive comparisons with other tyrannosauroids. This monographic description provides further evidence that Alioramus is an unusual long-snouted, gracile, and slender-limbed taxon with an unpredecented degree of cranial ornamentation among tyrannosaurids and an extremely pneumatized skeleton.Anatomical comparisons indicate that the long skull of Alioramus is an autapomorphic feature that is proportionally longer (relative to femur length) than in any other known tyrannosaurid specimen, including juveniles, and that Alioramus is morphologically distinctive relative to similarly sized individuals of the contemporary and sympatric Tarbosaurus. The holotype specimen of A. altai belongs to a young individual, and many differences between it and the other known specimen of Alioramus (the holotype of A. remotus) may represent ontogenetic variation. The unusual longirostrine skull of Alioramus was largely produced by lengthening of the snout bones (maxilla, nasal, dentary, lacrimal, jugal), rather than the orbiotemporal bones (frontal, postorbital, squamosal, quadratojugal). The long snout, gracile skull bones, comparatively small attachment sites for jaw muscles, and lack of interlocking sutures and a robust orbital brow would have precluded the holotype individual from employing the characteristic "puncture-pull" feeding style of large-bodied adult tyrannosaurids, in which the muscular jaws, thick teeth, and interlocking sutures enabled individuals to bite with enough force to fracture bone. Whether adult Alioramus could utilize "puncture-pull" feeding awaits discovery of mature individuals of the genus. The coexistence of the long-snouted Alioramus and robust and deep-snouted Tarbosaurus, which are found together at the Tsaagan Khuushu locality, demonstrate that multiple large tyrannosaurids were able to live in sympatry, likely because of niche partitioning due to differences in craniofacial morphology and functional behavior.

@article{doi1012067701,
    author = "Brusatte, Stephen L. and Carr, Thomas D. and Norell, Mark A.",
    title = "The Osteology of Alioramus, A Gracile and Long-Snouted Tyrannosaurid (Dinosauria: Theropoda) from the Late Cretaceous of Mongolia",
    year = "2012",
    journal = "Bulletin of the American Museum of Natural History",
    abstract = {The Late Cretaceous tyrannosaurid theropod Alioramus has long been one of the most puzzling large carnivorous dinosaur taxa, largely because for several decades it has been represented only by a single, fragmentary specimen that seems to represent a long-snouted and gracile individual but is difficult to interpret. The discovery of a substantially complete skeleton of Alioramus at the Tsaagan Khuushu locality in the Maastrichtian Nemegt Formation of Mongolia, recovered during the 2001 American Museum–Mongolian Academy of Sciences expedition and described as a new species (Alioramus altai) in 2009, definitively shows that this mysterious taxon is a distinct form of longirostrine tyrannosaurid that lived alongside the larger and more robust Tarbosaurus. Here we describe and figure this remarkably preserved skeleton in detail. We provide exhaustive descriptions and photographs of individual bones, and make extensive comparisons with other tyrannosauroids. This monographic description provides further evidence that Alioramus is an unusual long-snouted, gracile, and slender-limbed taxon with an unpredecented degree of cranial ornamentation among tyrannosaurids and an extremely pneumatized skeleton.Anatomical comparisons indicate that the long skull of Alioramus is an autapomorphic feature that is proportionally longer (relative to femur length) than in any other known tyrannosaurid specimen, including juveniles, and that Alioramus is morphologically distinctive relative to similarly sized individuals of the contemporary and sympatric Tarbosaurus. The holotype specimen of A. altai belongs to a young individual, and many differences between it and the other known specimen of Alioramus (the holotype of A. remotus) may represent ontogenetic variation. The unusual longirostrine skull of Alioramus was largely produced by lengthening of the snout bones (maxilla, nasal, dentary, lacrimal, jugal), rather than the orbiotemporal bones (frontal, postorbital, squamosal, quadratojugal). The long snout, gracile skull bones, comparatively small attachment sites for jaw muscles, and lack of interlocking sutures and a robust orbital brow would have precluded the holotype individual from employing the characteristic "puncture-pull" feeding style of large-bodied adult tyrannosaurids, in which the muscular jaws, thick teeth, and interlocking sutures enabled individuals to bite with enough force to fracture bone. Whether adult Alioramus could utilize "puncture-pull" feeding awaits discovery of mature individuals of the genus. The coexistence of the long-snouted Alioramus and robust and deep-snouted Tarbosaurus, which are found together at the Tsaagan Khuushu locality, demonstrate that multiple large tyrannosaurids were able to live in sympatry, likely because of niche partitioning due to differences in craniofacial morphology and functional behavior.},
    url = "https://doi.org/10.1206/770.1",
    doi = "10.1206/770.1",
    openalex = "W2042055098",
    references = "doi101007s001140090614x, doi10108002724634199710011003, doi101080027246342011557116, doi101111j109636421997tb00340x, doi101111j10963642200400130x, doi101126science1193304, doi101139e05044, doi10120600030082200635451andtfu20co2, doi10120637172, doi101371journalpone0017932, doi101671027246342003231apfast20co2, doi1016710272463420050250865hitrif20co2, doi104202app20080102, openalexw834136096, rauhut2003a"
}

BACKGROUND: The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian?--Aptian) of Utah has yielded a rich theropod fauna, including the coelurosaur Nedcolbertia justinhofmanni, the therizinosauroid Falcarius utahensis, the troodontid Geminiraptor suarezarum, and the dromaeosaurid Utahraptor ostrommaysorum. Recent excavation has uncovered three new dromaeosaurid specimens. One specimen, which we designate the holotype of the new genus and species Yurgovuchia doellingi, is represented by a partial axial skeleton and a partial left pubis. A second specimen consists of a right pubis and a possibly associated radius. The third specimen consists of a tail skeleton that is unique among known Cedar Mountain dromaeosaurids. METHODOLOGY/PRINCIPAL FINDINGS: Y. doellingi resembles Utahraptor ostrommaysorum in that its caudal prezygapophyses are elongated but not to the degree present in most dromaeosaurids. The specimen represented by the right pubis exhibits a pronounced pubic tubercle, a velociraptorine trait that is absent in Y. doellingi. The specimen represented by the tail skeleton exhibits the extreme elongation of the caudal prezygapophyses that is typical of most dromaeosaurids. Here we perform a phylogenetic analysis to determine the phylogenetic position of Y. doellingi. Using the resulting phylogeny as a framework, we trace changes in character states of the tail across Coelurosauria to elucidate the evolution of the dromaeosaurid tail. CONCLUSIONS/SIGNIFICANCE: The new specimens add to the known diversity of Dromaeosauridae and to the known diversity within the Yellow Cat paleofauna. Phylogenetic analysis places Y. doellingi in a clade with Utahraptor, Achillobator, and Dromaeosaurus. Character state distribution indicates that the presence of intermediate-length caudal prezygapophyses in that clade is not an evolutionarily precursor to extreme prezygapophyseal elongation but represents a secondary shortening of caudal prezygapophyses. It appears to represent part of a trend within Dromaeosauridae that couples an increase in tail flexibility with increasing size.

@article{doi101371journalpone0036790,
    author = "Senter, Phil and Kirkland, James I. and DeBlieux, Donald D. and Madsen, Scott K. and Toth, Natalie",
    title = "New Dromaeosaurids (Dinosauria: Theropoda) from the Lower Cretaceous of Utah, and the Evolution of the Dromaeosaurid Tail",
    year = "2012",
    journal = "PLoS ONE",
    abstract = "BACKGROUND: The Yellow Cat Member of the Cedar Mountain Formation (Early Cretaceous, Barremian?--Aptian) of Utah has yielded a rich theropod fauna, including the coelurosaur Nedcolbertia justinhofmanni, the therizinosauroid Falcarius utahensis, the troodontid Geminiraptor suarezarum, and the dromaeosaurid Utahraptor ostrommaysorum. Recent excavation has uncovered three new dromaeosaurid specimens. One specimen, which we designate the holotype of the new genus and species Yurgovuchia doellingi, is represented by a partial axial skeleton and a partial left pubis. A second specimen consists of a right pubis and a possibly associated radius. The third specimen consists of a tail skeleton that is unique among known Cedar Mountain dromaeosaurids. METHODOLOGY/PRINCIPAL FINDINGS: Y. doellingi resembles Utahraptor ostrommaysorum in that its caudal prezygapophyses are elongated but not to the degree present in most dromaeosaurids. The specimen represented by the right pubis exhibits a pronounced pubic tubercle, a velociraptorine trait that is absent in Y. doellingi. The specimen represented by the tail skeleton exhibits the extreme elongation of the caudal prezygapophyses that is typical of most dromaeosaurids. Here we perform a phylogenetic analysis to determine the phylogenetic position of Y. doellingi. Using the resulting phylogeny as a framework, we trace changes in character states of the tail across Coelurosauria to elucidate the evolution of the dromaeosaurid tail. CONCLUSIONS/SIGNIFICANCE: The new specimens add to the known diversity of Dromaeosauridae and to the known diversity within the Yellow Cat paleofauna. Phylogenetic analysis places Y. doellingi in a clade with Utahraptor, Achillobator, and Dromaeosaurus. Character state distribution indicates that the presence of intermediate-length caudal prezygapophyses in that clade is not an evolutionarily precursor to extreme prezygapophyseal elongation but represents a secondary shortening of caudal prezygapophyses. It appears to represent part of a trend within Dromaeosauridae that couples an increase in tail flexibility with increasing size.",
    url = "https://doi.org/10.1371/journal.pone.0036790",
    doi = "10.1371/journal.pone.0036790",
    openalex = "W2167644451",
    references = "doi101017cbo9780511536045, doi10103835047056, doi101038nature01342, doi10108002724634199610011283, doi101098rspl18870117, doi101126science13234331023, doi101371journalpone0014329, doi102475ajss319111253, doi105281zenodo16171435, openalexw2989049194, openalexw3215057009"
}

The Early Cretaceous fauna of Victoria, Australia, provides unique data on the composition of high latitude southern hemisphere dinosaurs. We describe and review theropod dinosaur postcranial remains from the Aptian-Albian Otway and Strzelecki groups, based on at least 37 isolated bones, and more than 90 teeth from the Flat Rocks locality. Several specimens of medium- and large-bodied individuals (estimated up to ~8.5 metres long) represent allosauroids. Tyrannosauroids are represented by elements indicating medium body sizes (~3 metres long), likely including the holotype femur of Timimus hermani, and a single cervical vertebra represents a juvenile spinosaurid. Single specimens representing medium- and small-bodied theropods may be referrable to Ceratosauria, Ornithomimosauria, a basal coelurosaur, and at least three taxa within Maniraptora. Thus, nine theropod taxa may have been present. Alternatively, four distinct dorsal vertebrae indicate a minimum of four taxa. However, because most taxa are known from single bones, it is likely that small-bodied theropod diversity remains underestimated. The high abundance of allosauroids and basal coelurosaurs (including tyrannosauroids and possibly ornithomimosaurs), and the relative rarity of ceratosaurs, is strikingly dissimilar to penecontemporaneous dinosaur faunas of Africa and South America, which represent an arid, lower-latitude biome. Similarities between dinosaur faunas of Victoria and the northern continents concern the proportional representatation of higher clades, and may result from the prevailing temperate-polar climate of Australia, especially at high latitudes in Victoria, which is similar to the predominant warm-temperate climate of Laurasia, but distinct from the arid climate zone that covered extensive areas of Gondwana. Most dinosaur groups probably attained a near-cosmopolitan distribution in the Jurassic, prior to fragmentation of the Pangaean supercontinent, and some aspects of the hallmark 'Gondwanan' fauna of South America and Africa may therefore reflect climate-driven provinciality, not vicariant evolution driven by continental fragmentation. However, vicariance may still be detected at lower phylogenetic levels.

@article{doi101371journalpone0037122,
    author = "Benson, Roger and Rich, Thomas H. and Vickers-Rich, Patricia and Hall, Mike",
    title = "Theropod Fauna from Southern Australia Indicates High Polar Diversity and Climate-Driven Dinosaur Provinciality",
    year = "2012",
    journal = "PLoS ONE",
    abstract = "The Early Cretaceous fauna of Victoria, Australia, provides unique data on the composition of high latitude southern hemisphere dinosaurs. We describe and review theropod dinosaur postcranial remains from the Aptian-Albian Otway and Strzelecki groups, based on at least 37 isolated bones, and more than 90 teeth from the Flat Rocks locality. Several specimens of medium- and large-bodied individuals (estimated up to \textasciitilde 8.5 metres long) represent allosauroids. Tyrannosauroids are represented by elements indicating medium body sizes (\textasciitilde 3 metres long), likely including the holotype femur of Timimus hermani, and a single cervical vertebra represents a juvenile spinosaurid. Single specimens representing medium- and small-bodied theropods may be referrable to Ceratosauria, Ornithomimosauria, a basal coelurosaur, and at least three taxa within Maniraptora. Thus, nine theropod taxa may have been present. Alternatively, four distinct dorsal vertebrae indicate a minimum of four taxa. However, because most taxa are known from single bones, it is likely that small-bodied theropod diversity remains underestimated. The high abundance of allosauroids and basal coelurosaurs (including tyrannosauroids and possibly ornithomimosaurs), and the relative rarity of ceratosaurs, is strikingly dissimilar to penecontemporaneous dinosaur faunas of Africa and South America, which represent an arid, lower-latitude biome. Similarities between dinosaur faunas of Victoria and the northern continents concern the proportional representatation of higher clades, and may result from the prevailing temperate-polar climate of Australia, especially at high latitudes in Victoria, which is similar to the predominant warm-temperate climate of Laurasia, but distinct from the arid climate zone that covered extensive areas of Gondwana. Most dinosaur groups probably attained a near-cosmopolitan distribution in the Jurassic, prior to fragmentation of the Pangaean supercontinent, and some aspects of the hallmark 'Gondwanan' fauna of South America and Africa may therefore reflect climate-driven provinciality, not vicariant evolution driven by continental fragmentation. However, vicariance may still be detected at lower phylogenetic levels.",
    url = "https://doi.org/10.1371/journal.pone.0037122",
    doi = "10.1371/journal.pone.0037122",
    openalex = "W2083980191",
    references = "carpenter2005the, crossref1976allosaurus, doi1010160012821x89900186, doi101016jtoxlet200611011, doi10103831635, doi101038416816a, doi10108002724634199910011178, doi101080147720192010488045, doi101126science13334591105, doi101126science28454232137, doi101139e05044, doi101590s000137652011000100008, doi105281zenodo13315375, doi105281zenodo16171435, doi105860choice331556, doi105860choice393984"
}

@article{galton2012an,
    author = "Galton, Peter M. and Molnar, Ralph E.",
    title = "An unusually large theropod dinosaur tooth from the Kirkwood Formation (Lower Cretaceous) of South Africa",
    year = "2012",
    journal = "Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen",
    url = "https://doi.org/10.1127/0077-7749/2011/0204",
    doi = "10.1127/0077-7749/2011/0204",
    number = "1",
    openalex = "W2323166137",
    pages = "17-23",
    volume = "263"
}

A high-resolution biostratigraphic analysis of 287 dinosaurian macrofossils and 138 bonebeds in the Edmonton Group (Upper Cretaceous) of southern Alberta provides evidence for at least three dinosaurian assemblage zones in the Horseshoe Canyon Formation (HCFm). From bottom to top the zones comprise unique assemblages of ornithischians and are named as follows: (1) Edmontosaurus regalis – Pachyrhinosaurus canadensis (lower zone); (2) Hypacrosaurus altispinus – Saurolophus osborni (middle zone); and (3) Eotriceratops xerinsularis (upper zone). Whereas the lower and middle zones are well defined and based on abundant specimens, the validity of the uppermost zone (E. xerinsularis) is tentative because it is based on a single specimen and the absence of dinosaur taxa from lower in section. The transition from the lower to the middle zone coincides with the replacement of a warm-and-wet saturated deltaic setting by a cooler, coastal-plain landscape, characterized by seasonal rainfall and better-drained substrates. Whereas changes in rainfall and substrate drainage appear to have influenced the faunal change, changes in mean annual temperature and proximity to shoreline appear to have had little influence on faunal change. We speculate that the faunal change between the middle and upper zones also resulted from a change in climate, with ornithischian dinosaurs responding to the re-establishment of wetter-and-warmer climates and poorly-drained substrates. Compared with the shorter-duration and climatically-consistent dinosaurian assemblage zones in the older Dinosaur Park Formation of southern Alberta, HCFm assemblage zones record long-term morphological stasis in dinosaurs. Furthermore, the coincidence of faunal and paleoenvironmental changes in the HCFm suggest climate-change-driven dinosaur migrations into and out of the region.

@article{doi101139cjes20120185,
    author = "Eberth, David A. and Evans, David C. and Brinkman, Donald B. and Therrien, François and Tanke, Darren H. and Russell, Loris S.",
    title = "Dinosaur biostratigraphy of the Edmonton Group (Upper Cretaceous), Alberta, Canada: evidence for climate influence",
    year = "2013",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "A high-resolution biostratigraphic analysis of 287 dinosaurian macrofossils and 138 bonebeds in the Edmonton Group (Upper Cretaceous) of southern Alberta provides evidence for at least three dinosaurian assemblage zones in the Horseshoe Canyon Formation (HCFm). From bottom to top the zones comprise unique assemblages of ornithischians and are named as follows: (1) Edmontosaurus regalis – Pachyrhinosaurus canadensis (lower zone); (2) Hypacrosaurus altispinus – Saurolophus osborni (middle zone); and (3) Eotriceratops xerinsularis (upper zone). Whereas the lower and middle zones are well defined and based on abundant specimens, the validity of the uppermost zone (E. xerinsularis) is tentative because it is based on a single specimen and the absence of dinosaur taxa from lower in section. The transition from the lower to the middle zone coincides with the replacement of a warm-and-wet saturated deltaic setting by a cooler, coastal-plain landscape, characterized by seasonal rainfall and better-drained substrates. Whereas changes in rainfall and substrate drainage appear to have influenced the faunal change, changes in mean annual temperature and proximity to shoreline appear to have had little influence on faunal change. We speculate that the faunal change between the middle and upper zones also resulted from a change in climate, with ornithischian dinosaurs responding to the re-establishment of wetter-and-warmer climates and poorly-drained substrates. Compared with the shorter-duration and climatically-consistent dinosaurian assemblage zones in the older Dinosaur Park Formation of southern Alberta, HCFm assemblage zones record long-term morphological stasis in dinosaurs. Furthermore, the coincidence of faunal and paleoenvironmental changes in the HCFm suggest climate-change-driven dinosaur migrations into and out of the region.",
    url = "https://doi.org/10.1139/cjes-2012-0185",
    doi = "10.1139/cjes-2012-0185",
    openalex = "W2157353435",
    references = "doi101016jpalaeo201206024, doi101016jpalaeo201206027, doi101017cbo9780511536045020, doi101098rspb20090352, doi101126science1177265, doi1011270078042120120020, doi101139e10005, doi101139e11017, doi101139e72031, doi101139e93016, doi10130683d923ed16c711d78645000102c1865d, doi101371journalpone0016574, doi101371journalpone0025186, doi104202app20110033, doi105281zenodo3725717, horner2011dinosaur, openalexw2989049194, sternberg1926notes"
}

The dinosaur record in the South Pyrenees Basin is diverse and rich. A total of 142 theropod teeth were studied for this paper, which constitutes one of the richest samples for these remains in Europe. Eight upper Campanian to upper Maastrichtian outcrops from the Pyrenees produced six non-avian theropod taxa (Theropoda indet., Coelurosauria indet.,?Richardoestesia,?Dromaeosauridae indet.,?Pyroraptor olympius,?Paronychodon). These six taxa are added to two previously described theropods (a Richardoestesia-like form and a possible ornithomimosaurid), indicating that there was considerable theropod diversity on the Iberian Peninsula during the Late Cretaceous.

@article{doi104202app20120121,
    author = "Torices, Angélica",
    title = "Theropod dinosaurs from the Upper Cretaceous of the South Pyrenees Basin of Spain",
    year = "2013",
    journal = "Acta Palaeontologica Polonica",
    abstract = "The dinosaur record in the South Pyrenees Basin is diverse and rich. A total of 142 theropod teeth were studied for this paper, which constitutes one of the richest samples for these remains in Europe. Eight upper Campanian to upper Maastrichtian outcrops from the Pyrenees produced six non-avian theropod taxa (Theropoda indet., Coelurosauria indet.,?Richardoestesia,?Dromaeosauridae indet.,?Pyroraptor olympius,?Paronychodon). These six taxa are added to two previously described theropods (a Richardoestesia-like form and a possible ornithomimosaurid), indicating that there was considerable theropod diversity on the Iberian Peninsula during the Late Cretaceous.",
    url = "https://doi.org/10.4202/app.2012.0121",
    doi = "10.4202/app.2012.0121",
    openalex = "W2108699011",
    references = "doi101016jpgeola201205008, doi101017cbo9780511608377011, doi101017s1477201907002246, doi101038nature02898, doi101098rspb20042692, doi101126science1144066, doi1016710272463420020220510toomka20co2, doi102475ajss32313381, doi104202app20110144, doi105281zenodo16171435, doi105962p226819, lindgren2008theropod, openalexw1846256677, openalexw3215057009"
}

The osteology of Diamantinasaurus matildae, the most complete Cretaceous sauropod described from Australia to date, is comprehensively reassessed. The preparation of additional material from the type locality, pertaining to the same individual as the holotype, sheds light on the morphology of the axial skeleton and provides additional information on the appendicular skeleton. The new material comprises two dorsal vertebrae, an incomplete sacrum (including four partial coalesced vertebrae), the right coracoid, the right radius, an additional manual phalanx, and a previously missing portion of the right fibula. In this study we identify thirteen autapomorphic characters of Diamantinasaurus, and an additional five characters that are locally autapomorphic within Titanosauriformes. This work provided an opportunity to revisit the phylogenetic placement of Diamantinasaurus. In two independent data matrices, Diamantinasaurus was recovered within Lithostrotia. One analysis resolved Diamantinasaurus as the sister taxon to the approximately coeval Tapuiasaurus from Brazil, whereas the second analysis recovered Diamantinasaurus as the sister taxon to Opisthocoelicaudia from the latest Cretaceous of Mongolia. The characters supporting the recovered relationships are analysed, and the palaeobiogeographical implications of the lithostrotian status of Diamantinasaurus are explored. A brief review of the body fossil record of Australian Cretaceous terrestrial vertebrates suggests close ties to South America in particular, and to Gondwana more generally.

@article{doi101016jgr201403014,
    author = "Poropat, Stephen F. and Upchurch, Paul and Mannion, Philip D. and Hocknull, Scott and Kear, Benjamin P. and Sloan, Trish and Sinapius, George H. K. and Elliott, David A.",
    title = "Revision of the sauropod dinosaur Diamantinasaurus matildae Hocknull et al. 2009 from the mid-Cretaceous of Australia: Implications for Gondwanan titanosauriform dispersal",
    year = "2014",
    journal = "Gondwana Research",
    abstract = "The osteology of Diamantinasaurus matildae, the most complete Cretaceous sauropod described from Australia to date, is comprehensively reassessed. The preparation of additional material from the type locality, pertaining to the same individual as the holotype, sheds light on the morphology of the axial skeleton and provides additional information on the appendicular skeleton. The new material comprises two dorsal vertebrae, an incomplete sacrum (including four partial coalesced vertebrae), the right coracoid, the right radius, an additional manual phalanx, and a previously missing portion of the right fibula. In this study we identify thirteen autapomorphic characters of Diamantinasaurus, and an additional five characters that are locally autapomorphic within Titanosauriformes. This work provided an opportunity to revisit the phylogenetic placement of Diamantinasaurus. In two independent data matrices, Diamantinasaurus was recovered within Lithostrotia. One analysis resolved Diamantinasaurus as the sister taxon to the approximately coeval Tapuiasaurus from Brazil, whereas the second analysis recovered Diamantinasaurus as the sister taxon to Opisthocoelicaudia from the latest Cretaceous of Mongolia. The characters supporting the recovered relationships are analysed, and the palaeobiogeographical implications of the lithostrotian status of Diamantinasaurus are explored. A brief review of the body fossil record of Australian Cretaceous terrestrial vertebrates suggests close ties to South America in particular, and to Gondwana more generally.",
    url = "https://doi.org/10.1016/j.gr.2014.03.014",
    doi = "10.1016/j.gr.2014.03.014",
    openalex = "W2077845776",
    references = "doi101016jcretres201304001, doi101046j10963642200200029x, doi101071bt00023, doi10108002724634199810011115, doi10108002724634199910011178, doi101098rspl18870117, doi101111j10960031200800217x, doi1023071292217, doi102475ajss319111253, doi107312kiel11918, openalexw3215057009"
}

The Salamanca Formation of the San Jorge Basin (Patagonia, Argentina) preserves critical records of Southern Hemisphere Paleo cene biotas, but its age remains poorly resolved, with estimates ranging from Late Cretaceous to middle Paleocene. We report a multi-disciplinary geochronologic study of the Salamanca Formation and overlying Ro Chico Group in the western part of the basin. New constraints include (1) an 40 Ar/ 39 Ar age determination of 67.31 0.55 Ma from a basalt fl ow underlying the Salamanca Formation, (2) micropaleontological results indicating an early Danian age for the base of the Salamanca Formation, (3) laser ablation HR-MC-ICP-MS (high resolutionmulti collector-inductively coupled plasmamass spectrometry) U-Pb ages and a high-resolution TIMS (thermal ionization mass spectrometry) age of 61.984 0.041(0.074) [0.100] Ma for zircons from volcanic ash beds in the Peas Coloradas Formation (Ro Chico Group), and (4) paleomagnetic results indicating that the Salamanca Formation in this area is entirely of normal polarity, with reversals occurring in the Ro Chico Group. Placing these new age constraints in the context of a sequence stratigraphic model for the basin, we correlate the Salamanca Formation in the study area to Chrons C29n and C28n, with the Banco Negro Inferior (BNI), a mature widespread fossiliferous paleosol unit at the top of the Salamanca Formation, corresponding to the top of Chron C28n. The diverse paleo botanical assemblages from this area are here assigned to C28n (64.67-63.49 Ma), ~2-3 million years older than previously thought, adding to growing evidence for rapid Southern Hemisphere fl oral recovery after the Cretaceous-Paleogene extinction. Important Peligran and "Carodnia" zone vertebrate fossil assemblages from coastal BNI and Peas Coloradas exposures are likely older than previously thought and correlate to the early Torrejonian and early Tiffanian North American Land Mammal Ages, respectively.

@article{doi101130b309151,
    author = "Clyde, William C. and Wilf, Peter and Iglesias, Ari and Slingerland, Rudy and Barnum, Timothy and Bijl, Peter K. and Bralower, Timothy J. and Brinkhuis, Henk and Comer, Emily Elizabeth and Huber, Brian T. and Ibáñez-Mejía, Mauricio and Jicha, Brian R. and Krause, J. Marcelo and Schueth, Jonathan D. and Singer, Brad S. and Raigemborn, M. Sol and Schmitz, Mark D. and Sluijs, Appy and del Carmen Zamaloa, María",
    title = "New age constraints for the Salamanca Formation and lower Rio Chico Group in the western San Jorge Basin, Patagonia, Argentina: Implications for Cretaceous-Paleogene extinction recovery and land mammal age correlations",
    year = "2014",
    journal = "Geological Society of America Bulletin",
    abstract = {The Salamanca Formation of the San Jorge Basin (Patagonia, Argentina) preserves critical records of Southern Hemisphere Paleo cene biotas, but its age remains poorly resolved, with estimates ranging from Late Cretaceous to middle Paleocene. We report a multi-disciplinary geochronologic study of the Salamanca Formation and overlying Ro Chico Group in the western part of the basin. New constraints include (1) an 40 Ar/ 39 Ar age determination of 67.31 0.55 Ma from a basalt fl ow underlying the Salamanca Formation, (2) micropaleontological results indicating an early Danian age for the base of the Salamanca Formation, (3) laser ablation HR-MC-ICP-MS (high resolutionmulti collector-inductively coupled plasmamass spectrometry) U-Pb ages and a high-resolution TIMS (thermal ionization mass spectrometry) age of 61.984 0.041(0.074) [0.100] Ma for zircons from volcanic ash beds in the Peas Coloradas Formation (Ro Chico Group), and (4) paleomagnetic results indicating that the Salamanca Formation in this area is entirely of normal polarity, with reversals occurring in the Ro Chico Group. Placing these new age constraints in the context of a sequence stratigraphic model for the basin, we correlate the Salamanca Formation in the study area to Chrons C29n and C28n, with the Banco Negro Inferior (BNI), a mature widespread fossiliferous paleosol unit at the top of the Salamanca Formation, corresponding to the top of Chron C28n. The diverse paleo botanical assemblages from this area are here assigned to C28n (64.67-63.49 Ma), \textasciitilde 2-3 million years older than previously thought, adding to growing evidence for rapid Southern Hemisphere fl oral recovery after the Cretaceous-Paleogene extinction. Important Peligran and "Carodnia" zone vertebrate fossil assemblages from coastal BNI and Peas Coloradas exposures are likely older than previously thought and correlate to the early Torrejonian and early Tiffanian North American Land Mammal Ages, respectively.},
    url = "https://doi.org/10.1130/b30915.1",
    doi = "10.1130/b30915.1",
    openalex = "W2139693275",
    references = "casal2009dientes, doi1010079781489957603, doi1010160012821x77900607, doi101029gl017i002p00159, doi101103physrevc41889, doi101111j1365246x1980tb02601x, doi101126science1059412, doi101126science1154339, doi101126science1177265, doi101130b306601, doi101146annurevearth050212124217, doi101371journalpone0052455, openalexw2797914455, openalexw62718268"
}

Quetecsaurus rusconii gen. et sp. nov. is a new titanosaur (Dinosauria, Sauropoda) from the Neuquén Basin of Mendoza Province, Argentina. The specimen comes from red mudstones of the Cerro Lisandro Formation (middle-late Turonian, Upper Cretaceous), and is the first sauropod with well-preserved remains to be discovered in this formation. The holotype includes a postorbital, teeth, the atlas, a posterior cervical vertebra, an incomplete dorsal vertebra, a posterior caudal centrum, dorsal ribs, a coracoid, fragments of a humerus, radius and ulna, and five metacarpals. It is characterized by the following combination of autapomorphies: (1) intercentrum of atlas with a prominent anteroventral border and expanded posteroventral processes; (2) posterior cervical neural spines with incipient lateral expansions; and (3) humerus with strongly sigmoid proximal border, rounded proximomedial border, and angular proximolateral corner. A preliminary cladistic analysis placed Quetecsaurus as a sister taxon of Lognkosauria (Mendozasaurus Futalognkosaurus). Quetecsaurus shares with the lognkosaurs the presence of cervical neural spines with ‘lateral laminae’, but relatively reduced in comparison with those taxa. This discovery provides new information on the diagnosis of Lognkosauria within South American titanosaurs.

@article{doi105710amegh261210131889,
    author = "Riga, Bernardo J. González and David, Leonardo Ortiz",
    title = "A New Titanosaur (Dinosauria, Sauropoda) from the Upper Cretaceous (Cerro Lisandro Formation) of Mendoza Province, Argentina",
    year = "2014",
    journal = "Ameghiniana",
    abstract = "Quetecsaurus rusconii gen. et sp. nov. is a new titanosaur (Dinosauria, Sauropoda) from the Neuquén Basin of Mendoza Province, Argentina. The specimen comes from red mudstones of the Cerro Lisandro Formation (middle-late Turonian, Upper Cretaceous), and is the first sauropod with well-preserved remains to be discovered in this formation. The holotype includes a postorbital, teeth, the atlas, a posterior cervical vertebra, an incomplete dorsal vertebra, a posterior caudal centrum, dorsal ribs, a coracoid, fragments of a humerus, radius and ulna, and five metacarpals. It is characterized by the following combination of autapomorphies: (1) intercentrum of atlas with a prominent anteroventral border and expanded posteroventral processes; (2) posterior cervical neural spines with incipient lateral expansions; and (3) humerus with strongly sigmoid proximal border, rounded proximomedial border, and angular proximolateral corner. A preliminary cladistic analysis placed Quetecsaurus as a sister taxon of Lognkosauria (Mendozasaurus Futalognkosaurus). Quetecsaurus shares with the lognkosaurs the presence of cervical neural spines with ‘lateral laminae’, but relatively reduced in comparison with those taxa. This discovery provides new information on the diagnosis of Lognkosauria within South American titanosaurs.",
    url = "https://doi.org/10.5710/amegh.26.12.1013.1889",
    doi = "10.5710/amegh.26.12.1013.1889",
    openalex = "W1968540694",
    references = "doi101017s247526300000091x, doi101046j10963642200200029x, doi10108002724634199810011115, doi10108002724634199910011178, doi101111j109636421998tb00569x, doi101371journalpone0017114, doi1022179revmacn7344, doi102475ajss319111253, doi105281zenodo16171435, openalexw2462998831, openalexw581267017"
}

Minmi is the only known genus of ankylosaurian dinosaur from Australia. Seven specimens are known, all from the Lower Cretaceous of Queensland. Only two of these have been described in any detail: the holotype specimen Minmi paravertebra from the Bungil Formation near Roma, and a near complete skeleton from the Allaru Mudstone on Marathon Station near Richmond, preliminarily referred to a possible new species of Minmi. The Marathon specimen represents one of the world's most complete ankylosaurian skeletons and the best-preserved dinosaurian fossil from eastern Gondwana. Moreover, among ankylosaurians, its skull is one of only a few in which the majority of sutures have not been obliterated by dermal ossifications or surface remodelling. Recent preparation of the Marathon specimen has revealed new details of the palate and narial regions, permitting a comprehensive description and thus providing new insights cranial osteology of a basal ankylosaurian. The skull has also undergone computed tomography, digital segmentation and 3D computer visualisation enabling the reconstruction of its nasal cavity and endocranium. The airways of the Marathon specimen are more complicated than non-ankylosaurian dinosaurs but less so than derived ankylosaurians. The cranial (brain) endocast is superficially similar to those of other ankylosaurians but is strongly divergent in many important respects. The inner ear is extremely large and unlike that of any dinosaur yet known. Based on a high number of diagnostic differences between the skull of the Marathon specimen and other ankylosaurians, we consider it prudent to assign this specimen to a new genus and species of ankylosaurian. Kunbarrasaurus ieversi gen. et sp. nov. represents the second genus of ankylosaurian from Australia and is characterised by an unusual melange of both primitive and derived characters, shedding new light on the evolution of the ankylosaurian skull.

@article{doi107717peerj1475,
    author = "Leahey, Lucy G. and Molnar, Ralph E. and Carpenter, Kenneth and Witmer, Lawrence M. and Salisbury, Steven W.",
    title = "Cranial osteology of the ankylosaurian dinosaur formerly known as Minmi sp. (Ornithischia: Thyreophora) from the Lower Cretaceous Allaru Mudstone of Richmond, Queensland, Australia",
    year = "2015",
    journal = "PeerJ",
    abstract = "Minmi is the only known genus of ankylosaurian dinosaur from Australia. Seven specimens are known, all from the Lower Cretaceous of Queensland. Only two of these have been described in any detail: the holotype specimen Minmi paravertebra from the Bungil Formation near Roma, and a near complete skeleton from the Allaru Mudstone on Marathon Station near Richmond, preliminarily referred to a possible new species of Minmi. The Marathon specimen represents one of the world's most complete ankylosaurian skeletons and the best-preserved dinosaurian fossil from eastern Gondwana. Moreover, among ankylosaurians, its skull is one of only a few in which the majority of sutures have not been obliterated by dermal ossifications or surface remodelling. Recent preparation of the Marathon specimen has revealed new details of the palate and narial regions, permitting a comprehensive description and thus providing new insights cranial osteology of a basal ankylosaurian. The skull has also undergone computed tomography, digital segmentation and 3D computer visualisation enabling the reconstruction of its nasal cavity and endocranium. The airways of the Marathon specimen are more complicated than non-ankylosaurian dinosaurs but less so than derived ankylosaurians. The cranial (brain) endocast is superficially similar to those of other ankylosaurians but is strongly divergent in many important respects. The inner ear is extremely large and unlike that of any dinosaur yet known. Based on a high number of diagnostic differences between the skull of the Marathon specimen and other ankylosaurians, we consider it prudent to assign this specimen to a new genus and species of ankylosaurian. Kunbarrasaurus ieversi gen. et sp. nov. represents the second genus of ankylosaurian from Australia and is characterised by an unusual melange of both primitive and derived characters, shedding new light on the evolution of the ankylosaurian skull.",
    url = "https://doi.org/10.7717/peerj.1475",
    doi = "10.7717/peerj.1475",
    openalex = "W2195920462",
    references = "doi101002ar20984, doi101016jgr201403014, doi1010801477201920151059985"
}

Australian dinosaurs have played a rare but controversial role in the debate surrounding the effect of Gondwanan break-up on Cretaceous dinosaur distribution. Major spatiotemporal gaps in the Gondwanan Cretaceous fossil record, coupled with taxon incompleteness, have hindered research on this effect, especially in Australia. Here we report on two new sauropod specimens from the early Late Cretaceous of Queensland, Australia, that have important implications for Cretaceous dinosaur palaeobiogeography. Savannasaurus elliottorum gen. et sp. nov. comprises one of the most complete Cretaceous sauropod skeletons ever found in Australia, whereas a new specimen of Diamantinasaurus matildae includes the first ever cranial remains of an Australian sauropod. The results of a new phylogenetic analysis, in which both Savannasaurus and Diamantinasaurus are recovered within Titanosauria, were used as the basis for a quantitative palaeobiogeographical analysis of macronarian sauropods. Titanosaurs achieved a worldwide distribution by at least 125 million years ago, suggesting that mid-Cretaceous Australian sauropods represent remnants of clades which were widespread during the Early Cretaceous. These lineages would have entered Australasia via dispersal from South America, presumably across Antarctica. High latitude sauropod dispersal might have been facilitated by Albian-Turonian warming that lifted a palaeoclimatic dispersal barrier between Antarctica and South America.

@article{doi101038srep34467,
    author = "Poropat, Stephen F. and Mannion, Philip D. and Upchurch, Paul and Hocknull, Scott and Kear, Benjamin P. and Kundrát, Martin and Tischler, Travis R. and Sloan, Trish and Sinapius, George H. K. and Elliott, Judy A. and Elliott, David A.",
    title = "New Australian sauropods shed light on Cretaceous dinosaur palaeobiogeography",
    year = "2016",
    journal = "Scientific Reports",
    abstract = "Australian dinosaurs have played a rare but controversial role in the debate surrounding the effect of Gondwanan break-up on Cretaceous dinosaur distribution. Major spatiotemporal gaps in the Gondwanan Cretaceous fossil record, coupled with taxon incompleteness, have hindered research on this effect, especially in Australia. Here we report on two new sauropod specimens from the early Late Cretaceous of Queensland, Australia, that have important implications for Cretaceous dinosaur palaeobiogeography. Savannasaurus elliottorum gen. et sp. nov. comprises one of the most complete Cretaceous sauropod skeletons ever found in Australia, whereas a new specimen of Diamantinasaurus matildae includes the first ever cranial remains of an Australian sauropod. The results of a new phylogenetic analysis, in which both Savannasaurus and Diamantinasaurus are recovered within Titanosauria, were used as the basis for a quantitative palaeobiogeographical analysis of macronarian sauropods. Titanosaurs achieved a worldwide distribution by at least 125 million years ago, suggesting that mid-Cretaceous Australian sauropods represent remnants of clades which were widespread during the Early Cretaceous. These lineages would have entered Australasia via dispersal from South America, presumably across Antarctica. High latitude sauropod dispersal might have been facilitated by Albian-Turonian warming that lifted a palaeoclimatic dispersal barrier between Antarctica and South America.",
    url = "https://doi.org/10.1038/srep34467",
    doi = "10.1038/srep34467",
    openalex = "W2535200874",
    references = "doi101016jcretres201304001, doi101016jearscirev201203002, doi101016jgr201212009, doi101016jgr201403014, doi101038srep19165, doi101046j10963642200200029x, doi10108014772011003594870, doi1010801477201920151059985, doi101111j10960031200800217x, doi101111j109636421998tb00569x, doi101111zoj12029, doi101126science1116412, doi101126science2725264986, doi1011300016760619951071164mlccot23co2, doi101371journalpone0006190, doi101371journalpone0037122, doi101371journalpone0125819, doi1015259780520941434, doi1021425f55419694, doi1021425f5fbg19694, doi105194cp813232012, doi107717peerj1523, openalexw2173200745"
}

Extensive and well-preserved tracksites in the coastally exposed Lower Cretaceous (Valanginian–Barremian) Broome Sandstone of the Dampier Peninsula provide almost the entire fossil record of dinosaurs from the western half of the Australian continent. Tracks near the town of Broome were described in the late 1960s as Megalosauropus broomensis and attributed to a medium-sized theropod trackmaker. Brief reports in the early 1990s suggested the occurrence of at least another nine types of tracks, referable to theropod, sauropod, ornithopod, and thyreophoran trackmakers, at scattered tracksites spread over more than 80 km of coastline north of Broome, potentially representing one of the world's most diverse dinosaurian ichnofaunas. More recently, it has been proposed that this number could be as high as 16 and that the sites are spread over more than 200 km. However, the only substantial research that has been published on these more recent discoveries is a preliminary study of the sauropod tracks and an account of the ways in which the heavy passage of sauropod trackmakers may have shaped the Dampier Peninsula's Early Cretaceous landscape. With the other types of dinosaurian tracks in the Broome Sandstone remaining undescribed, and the full extent and nature of the Dampier Peninsula's dinosaurian tracksites yet to be adequately addressed, the overall scientific significance of the ichnofauna has remained enigmatic. At the request of the area's Goolarabooloo Traditional Custodians, 400+ hours of ichnological survey work was undertaken from 2011 to 2016 on the 25 km stretch of coastline in the Yanijarri–Lurujarri section of the Dampier Peninsula, inclusive of the coastline at Walmadany (James Price Point). Forty-eight discrete dinosaurian tracksites were identified in this area, and thousands of tracks were examined and measured in situ and using three-dimensional photogrammetry. Tracksites were concentrated in three main areas along the coast: Yanijarri in the north, Walmadany in the middle, and Kardilakan–Jajal Buru in the south. Lithofacies analysis revealed 16 repeated facies types that occurred in three distinctive lithofacies associations, indicative of an environmental transgression between the distal fluvial to deltaic portions of a large braid plain, with migrating sand bodies and periodic sheet floods. The main dinosaurian track-bearing horizons seem to have been generated between periodic sheet floods that blanketed the preexisting sand bodies within the braid plain portion of a tidally influenced delta, with much of the original, gently undulating topography now preserved over large expanses of the present day intertidal reef system. Of the tracks examined, 150 could be identified and are assignable to a least eleven and possibly as many as 21 different track types: five different types of theropod tracks, at least six types of sauropod tracks, four types of ornithopod tracks, and six types of thyreophoran tracks. Eleven of these track types can formally be assigned or compared to existing or new ichnotaxa, whereas the remaining ten represent morphotypes that, although distinct, are currently too poorly represented to confidently assign to existing or new ichnotaxa. Among the ichnotaxa that we have recognized, only two (Megalosauropus broomensis and Wintonopus latomorum) belong to existing ichnotaxa, and two compare to existing ichnotaxa but display a suite of morphological features suggesting that they may be distinct in their own right and are therefore placed in open nomenclature. Six of the ichnotaxa that we have identified are new: one theropod ichnotaxon, Yangtzepus clarkei, ichnosp. nov.; one sauropod ichnotaxon, Oobardjidama foulkesi, ichnogen. et ichnosp. nov.; two ornithopod ichnotaxa, Wintonopus middletonae, ichnosp. nov., and Walmadanyichnus hunteri, ichnogen. et ichnosp. nov.; and two thyreophoran ichnotaxa, Garbina roeorum, ichnogen. et ichnosp. nov., and Luluichnus mueckei, ichnogen. et ichnosp. nov. The level of diversity of the main track types is comparable across areas where tracksites are concentrated: Kardilakan–Jajal Buru (12), Walmadany (11), and Yanijarri (10). The overall diversity of the dinosaurian ichnofauna of the Broome Sandstone in the Yanijarri–Lurujarri section of the Dampier Peninsula is unparalleled in Australia, and even globally. In addition to being the primary record of non-avian dinosaurs in the western half of Australia, this ichnofauna provides our only detailed glimpse of Australia's dinosaurian fauna during the first half of the Early Cretaceous. It indicates that the general composition of Australia's mid-Cretaceous dinosaurian fauna was already in place by the Valanginian–Barremian. Both sauropods and ornithopods were diverse and abundant, and thyreophorans were the only type of quadrupedal ornithischians. Important aspects of the fauna that are not seen in the Australian mid-Cretaceous body fossil record are the presence of stegosaurians, an overall higher diversity of thyreophorans and theropods, and the presence of large-bodied hadrosauroid-like ornithopods and very large-bodied sauropods. In many respects, these differences suggest a holdover from the Late Jurassic, when the majority of dinosaurian clades had a more cosmopolitan distribution prior to the fragmentation of Pangea. Although the record for the Lower Cretaceous of Gondwana is sparse, a similar mix of taxa occurs in the Barremian–lower Aptian La Amarga Formation of Argentina and the Berriasian–Hauterivian Kirkwood Formation of South Africa. The persistence of this fauna across the Jurassic-Cretaceous boundary in South America, Africa, and Australia might be characteristic of Gondwanan dinosaurian faunas more broadly. It suggests that the extinction event that affected Laurasian dinosaurian faunas across the Jurassic-Cretaceous boundary may not have been as extreme in Gondwana, and this difference may have foreshadowed the onset of Laurasian-Eurogondwanan provincialism. The disappearance of stegosaurians and the apparent drop in diversity of theropods by the mid-Cretaceous suggests that, similar to South America, Australia passed through a period of faunal turnover between the Valanginian and Aptian. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Salisbury, S. W., A. Romilio, M. C. Herne, R. T. Tucker, and J. P. Nair. 2017. The dinosaurian ichnofauna of the Lower Cretaceous (Valanginian–Barremian) Broome Sandstone of the Walmadany area (James Price Point), Dampier Peninsula, Western Australia. Society of Vertebrate Paleontology Memoir 16. Journal of Vertebrate Paleontology 36(6, Supplement). DOI: 10.1080/02724634.2016.1269539.

@article{doi1010800272463420161269539,
    author = "Salisbury, Steven W. and Romilio, Anthony and Herne, Matthew and Tucker, Ryan T. and Nair, Jay P.",
    title = "The Dinosaurian Ichnofauna of the Lower Cretaceous (Valanginian–Barremian) Broome Sandstone of the Walmadany Area (James Price Point), Dampier Peninsula, Western Australia",
    year = "2016",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "Extensive and well-preserved tracksites in the coastally exposed Lower Cretaceous (Valanginian–Barremian) Broome Sandstone of the Dampier Peninsula provide almost the entire fossil record of dinosaurs from the western half of the Australian continent. Tracks near the town of Broome were described in the late 1960s as Megalosauropus broomensis and attributed to a medium-sized theropod trackmaker. Brief reports in the early 1990s suggested the occurrence of at least another nine types of tracks, referable to theropod, sauropod, ornithopod, and thyreophoran trackmakers, at scattered tracksites spread over more than 80 km of coastline north of Broome, potentially representing one of the world's most diverse dinosaurian ichnofaunas. More recently, it has been proposed that this number could be as high as 16 and that the sites are spread over more than 200 km. However, the only substantial research that has been published on these more recent discoveries is a preliminary study of the sauropod tracks and an account of the ways in which the heavy passage of sauropod trackmakers may have shaped the Dampier Peninsula's Early Cretaceous landscape. With the other types of dinosaurian tracks in the Broome Sandstone remaining undescribed, and the full extent and nature of the Dampier Peninsula's dinosaurian tracksites yet to be adequately addressed, the overall scientific significance of the ichnofauna has remained enigmatic. At the request of the area's Goolarabooloo Traditional Custodians, 400+ hours of ichnological survey work was undertaken from 2011 to 2016 on the 25 km stretch of coastline in the Yanijarri–Lurujarri section of the Dampier Peninsula, inclusive of the coastline at Walmadany (James Price Point). Forty-eight discrete dinosaurian tracksites were identified in this area, and thousands of tracks were examined and measured in situ and using three-dimensional photogrammetry. Tracksites were concentrated in three main areas along the coast: Yanijarri in the north, Walmadany in the middle, and Kardilakan–Jajal Buru in the south. Lithofacies analysis revealed 16 repeated facies types that occurred in three distinctive lithofacies associations, indicative of an environmental transgression between the distal fluvial to deltaic portions of a large braid plain, with migrating sand bodies and periodic sheet floods. The main dinosaurian track-bearing horizons seem to have been generated between periodic sheet floods that blanketed the preexisting sand bodies within the braid plain portion of a tidally influenced delta, with much of the original, gently undulating topography now preserved over large expanses of the present day intertidal reef system. Of the tracks examined, 150 could be identified and are assignable to a least eleven and possibly as many as 21 different track types: five different types of theropod tracks, at least six types of sauropod tracks, four types of ornithopod tracks, and six types of thyreophoran tracks. Eleven of these track types can formally be assigned or compared to existing or new ichnotaxa, whereas the remaining ten represent morphotypes that, although distinct, are currently too poorly represented to confidently assign to existing or new ichnotaxa. Among the ichnotaxa that we have recognized, only two (Megalosauropus broomensis and Wintonopus latomorum) belong to existing ichnotaxa, and two compare to existing ichnotaxa but display a suite of morphological features suggesting that they may be distinct in their own right and are therefore placed in open nomenclature. Six of the ichnotaxa that we have identified are new: one theropod ichnotaxon, Yangtzepus clarkei, ichnosp. nov.; one sauropod ichnotaxon, Oobardjidama foulkesi, ichnogen. et ichnosp. nov.; two ornithopod ichnotaxa, Wintonopus middletonae, ichnosp. nov., and Walmadanyichnus hunteri, ichnogen. et ichnosp. nov.; and two thyreophoran ichnotaxa, Garbina roeorum, ichnogen. et ichnosp. nov., and Luluichnus mueckei, ichnogen. et ichnosp. nov. The level of diversity of the main track types is comparable across areas where tracksites are concentrated: Kardilakan–Jajal Buru (12), Walmadany (11), and Yanijarri (10). The overall diversity of the dinosaurian ichnofauna of the Broome Sandstone in the Yanijarri–Lurujarri section of the Dampier Peninsula is unparalleled in Australia, and even globally. In addition to being the primary record of non-avian dinosaurs in the western half of Australia, this ichnofauna provides our only detailed glimpse of Australia's dinosaurian fauna during the first half of the Early Cretaceous. It indicates that the general composition of Australia's mid-Cretaceous dinosaurian fauna was already in place by the Valanginian–Barremian. Both sauropods and ornithopods were diverse and abundant, and thyreophorans were the only type of quadrupedal ornithischians. Important aspects of the fauna that are not seen in the Australian mid-Cretaceous body fossil record are the presence of stegosaurians, an overall higher diversity of thyreophorans and theropods, and the presence of large-bodied hadrosauroid-like ornithopods and very large-bodied sauropods. In many respects, these differences suggest a holdover from the Late Jurassic, when the majority of dinosaurian clades had a more cosmopolitan distribution prior to the fragmentation of Pangea. Although the record for the Lower Cretaceous of Gondwana is sparse, a similar mix of taxa occurs in the Barremian–lower Aptian La Amarga Formation of Argentina and the Berriasian–Hauterivian Kirkwood Formation of South Africa. The persistence of this fauna across the Jurassic-Cretaceous boundary in South America, Africa, and Australia might be characteristic of Gondwanan dinosaurian faunas more broadly. It suggests that the extinction event that affected Laurasian dinosaurian faunas across the Jurassic-Cretaceous boundary may not have been as extreme in Gondwana, and this difference may have foreshadowed the onset of Laurasian-Eurogondwanan provincialism. The disappearance of stegosaurians and the apparent drop in diversity of theropods by the mid-Cretaceous suggests that, similar to South America, Australia passed through a period of faunal turnover between the Valanginian and Aptian. SUPPLEMENTAL DATA—Supplemental materials are available for this article for free at www.tandfonline.com/UJVP Citation for this article: Salisbury, S. W., A. Romilio, M. C. Herne, R. T. Tucker, and J. P. Nair. 2017. The dinosaurian ichnofauna of the Lower Cretaceous (Valanginian–Barremian) Broome Sandstone of the Walmadany area (James Price Point), Dampier Peninsula, Western Australia. Society of Vertebrate Paleontology Memoir 16. Journal of Vertebrate Paleontology 36(6, Supplement). DOI: 10.1080/02724634.2016.1269539.",
    url = "https://doi.org/10.1080/02724634.2016.1269539",
    doi = "10.1080/02724634.2016.1269539",
    openalex = "W2602833024",
    references = "apesteguía2011tunasniyoj, deklerk2000a, doi101002mmng19994860020102, doi101007bf02988144, doi1010160012825277900551, doi1010160012825279900011, doi1010160012825285900017, doi101016002532279290061l, doi101016jcretres200908003, doi101016jcretres201304001, doi101016jcretres201307009, doi101016jgr201403014, doi101016jjafrearsci201205005, doi101016jsedgeo200610001, doi101016s001678780180047x, doi101017cbo9780511626487, doi101038srep06196, doi101038srep19165, doi101038srep34467, doi101046j14401738200300386x, doi10108000288306197010418211, doi10108002724634199810011086, doi10108008912960903503345, doi10108010420940109380189, doi10108010420940490428625, doi10108010420940601006859, doi10108011035890902924877, doi1010801477201920151059985, doi101093oxfordjournalsafrafa100309, doi101111j10963642201000620x, doi101111j10963642201000642x, doi101130g23452a1, doi101139e91009, doi101144pygs543185, doi101306212f83b92b2411d78648000102c1865d, doi101371journalpone0013120, doi101371journalpone0072579, doi101371journalpone0137709, doi1022179revmacn7344, doi1026879529, doi104095105049, doi104202app20080049, foster1995tridactyl, mateus2010a, nouri2011tetradactyl, openalexw1564145569, openalexw1592791648, openalexw2173200745, openalexw2618301958, openalexw2619609965, openalexw616953834"
}

Theropod dinosaurs from the Late Jurassic of Gondwana are still poorly known, with Elaphrosaurus bambergiJanensch, 1920, from the late Kimmeridgian of Tendaguru, Tanzania, being the only taxon represented by more than isolated remains from Africa. Having long been considered a coelurosaurian, more specifically an ornithomimosaur, Elaphrosaurus is currently regarded as a basal ceratosaur. Here, we revise the osteology and phylogenetic position of this important taxon. Elaphrosaurus shows many unusual osteological characters, including extremely elongated and constricted cervical vertebrae, an expansive shoulder girdle with strongly modified forelimbs, a relatively small ilium, and elongate hindlimbs with a very small ascending process of the astragalus that is fused to the tibia. We found this taxon to share many derived characters with noasaurids, such as: strongly elongate cervical and dorsal vertebrae; low, rectangular neural spines in the mid-caudal vertebrae; presence of only an anterior centrodiapophyseal lamina in anterior caudal vertebrae; presence of a wide, U–shaped notch between the glenoid and the anteroventral hook in the coracoid; a laterally flared postacetabular blade of the ilium; a flat anterior side of the distal tibia; and a reduced shaft of metatarsal II. Our analysis placed Elaphrosaurus within a dichotomous Noasauridae as part of a Jurassic subclade, here termed Elaphrosaurinae, that otherwise includes taxa from eastern Asia. These results underscore the long and complex evolutionary history of abelisauroids, which is still only beginning to be understood.

@article{doi101111zoj12425,
    author = "Rauhut, Oliver W. M. and Carrano, Matthew T.",
    title = "The theropod dinosaur Elaphrosaurus bambergi Janensch, 1920, from the Late Jurassic of Tendaguru, Tanzania",
    year = "2016",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "Theropod dinosaurs from the Late Jurassic of Gondwana are still poorly known, with Elaphrosaurus bambergiJanensch, 1920, from the late Kimmeridgian of Tendaguru, Tanzania, being the only taxon represented by more than isolated remains from Africa. Having long been considered a coelurosaurian, more specifically an ornithomimosaur, Elaphrosaurus is currently regarded as a basal ceratosaur. Here, we revise the osteology and phylogenetic position of this important taxon. Elaphrosaurus shows many unusual osteological characters, including extremely elongated and constricted cervical vertebrae, an expansive shoulder girdle with strongly modified forelimbs, a relatively small ilium, and elongate hindlimbs with a very small ascending process of the astragalus that is fused to the tibia. We found this taxon to share many derived characters with noasaurids, such as: strongly elongate cervical and dorsal vertebrae; low, rectangular neural spines in the mid-caudal vertebrae; presence of only an anterior centrodiapophyseal lamina in anterior caudal vertebrae; presence of a wide, U–shaped notch between the glenoid and the anteroventral hook in the coracoid; a laterally flared postacetabular blade of the ilium; a flat anterior side of the distal tibia; and a reduced shaft of metatarsal II. Our analysis placed Elaphrosaurus within a dichotomous Noasauridae as part of a Jurassic subclade, here termed Elaphrosaurinae, that otherwise includes taxa from eastern Asia. These results underscore the long and complex evolutionary history of abelisauroids, which is still only beginning to be understood.",
    url = "https://doi.org/10.1111/zoj.12425",
    doi = "10.1111/zoj.12425",
    openalex = "W2340352440",
    references = "crossref1998encyclopedia, doi101002mmng200900004, doi101016jcretres201304001, doi101016jpgeola201205008, doi101017s0016756804000330, doi101017s0025315400028575, doi10108002724634199610011283, doi101098rspb20120660, doi101098rspl18870117, doi1011112041210x12226, doi101111j10960031200800217x, doi101126science28454232137, doi101371journalpone0062047, doi102475ajss319111253, doi105281zenodo16171435, doi105860choice353642, openalexw1565584485, openalexw3215057009, openalexw3217097258"
}

A skeleton discovered in the Upper Cretaceous Sierra Barrosa Formation (Turonian-Coniacian) of Neuquén Province, Argentina represents a new species of theropod dinosaur related to the long snouted, highly pneumatized Megaraptoridae. The holotype specimen of Murusraptor barrosaensis n.gen et n.sp. (MCF-PVPH-411) includes much of the skull, axial skeleton, pelvis and tibia. Murusraptor is unique in having several diagnostic features that include anterodorsal process of lacrimal longer than height of preorbital process, and a thick, shelf-like thickening on the lateral surface of surangular ventral to the groove between the anterior surangular foramen and the insert for the uppermost intramandibular process of the dentary. Other characteristic features of Murusraptor barrosaensis n.gen. et n. sp.include a large mandibular fenestra, distal ends of caudal neural spines laterally thickened into lateral knob-like processes, short ischia distally flattened and slightly expanded dorsoventrally. Murusraptor belongs to a Patagonian radiation of megaraptorids together with Aerosteon, Megaraptor and Orkoraptor. In spite being immature, it is a larger but more gracile animal than existing specimens of Megaraptor, and is comparable in size with Aerosteon and Orkoraptor. The controversial phylogeny of the Megaraptoridae as members of the Allosauroidea or a clade of Coelurosauria is considered analyzing two alternative data sets.

@article{doi101371journalpone0157973,
    author = "Coria, Rodolfo A. and Currie, Philip J.",
    title = "A New Megaraptoran Dinosaur (Dinosauria, Theropoda, Megaraptoridae) from the Late Cretaceous of Patagonia",
    year = "2016",
    journal = "PLoS ONE",
    abstract = "A skeleton discovered in the Upper Cretaceous Sierra Barrosa Formation (Turonian-Coniacian) of Neuquén Province, Argentina represents a new species of theropod dinosaur related to the long snouted, highly pneumatized Megaraptoridae. The holotype specimen of Murusraptor barrosaensis n.gen et n.sp. (MCF-PVPH-411) includes much of the skull, axial skeleton, pelvis and tibia. Murusraptor is unique in having several diagnostic features that include anterodorsal process of lacrimal longer than height of preorbital process, and a thick, shelf-like thickening on the lateral surface of surangular ventral to the groove between the anterior surangular foramen and the insert for the uppermost intramandibular process of the dentary. Other characteristic features of Murusraptor barrosaensis n.gen. et n. sp.include a large mandibular fenestra, distal ends of caudal neural spines laterally thickened into lateral knob-like processes, short ischia distally flattened and slightly expanded dorsoventrally. Murusraptor belongs to a Patagonian radiation of megaraptorids together with Aerosteon, Megaraptor and Orkoraptor. In spite being immature, it is a larger but more gracile animal than existing specimens of Megaraptor, and is comparable in size with Aerosteon and Orkoraptor. The controversial phylogeny of the Megaraptoridae as members of the Allosauroidea or a clade of Coelurosauria is considered analyzing two alternative data sets.",
    url = "https://doi.org/10.1371/journal.pone.0157973",
    doi = "10.1371/journal.pone.0157973",
    openalex = "W2489898299",
    references = "doi101038ncomms3827, doi101371journalpone0017932, doi1022179revmacn12239"
}

Predator-prey dynamics are an important evolutionary driver of escalating predation mode and efficiency, and commensurate responses of prey [1-3]. Among these strategies, camouflage is important for visual concealment, with countershading the most universally observed [4-6]. Extant terrestrial herbivores free of significant predation pressure, due to large size or isolation, do not exhibit countershading. Modern predator-prey dynamics may not be directly applicable to those of the Mesozoic due to the dominance of very large, visually oriented theropod dinosaurs [7]. Despite thyreophoran dinosaurs' possessing extensive dermal armor, some of the most extreme examples of anti-predator structures [8, 9], little direct evidence of predation on these and other dinosaur megaherbivores has been documented. Here we describe a new, exquisitely three-dimensionally preserved nodosaurid ankylosaur, Borealopelta markmitchelli gen. et sp. nov., from the Early Cretaceous of Alberta, which preserves integumentary structures as organic layers, including continuous fields of epidermal scales and intact horn sheaths capping the body armor. We identify melanin in the organic residues through mass spectroscopic analyses and observe lighter pigmentation of the large parascapular spines, consistent with display, and a pattern of countershading across the body. With an estimated body mass exceeding 1,300 kg, B. markmitchelli was much larger than modern terrestrial mammals that either are countershaded or experience significant predation pressure as adults. Presence of countershading suggests predation pressure strong enough to select for concealment in this megaherbivore despite possession of massive dorsal and lateral armor, illustrating a significant dichotomy between Mesozoic predator-prey dynamics and those of modern terrestrial systems.

@article{doi101016jcub201706071,
    author = "Brown, Caleb M. and Henderson, Donald M. and Vinther, Jakob and Fletcher, Ian and Sistiaga, Ainara and Bethencourt, Jorsua Herrera and Summons, Roger E.",
    title = "An Exceptionally Preserved Three-Dimensional Armored Dinosaur Reveals Insights into Coloration and Cretaceous Predator-Prey Dynamics",
    year = "2017",
    journal = "Current Biology",
    abstract = "Predator-prey dynamics are an important evolutionary driver of escalating predation mode and efficiency, and commensurate responses of prey [1-3]. Among these strategies, camouflage is important for visual concealment, with countershading the most universally observed [4-6]. Extant terrestrial herbivores free of significant predation pressure, due to large size or isolation, do not exhibit countershading. Modern predator-prey dynamics may not be directly applicable to those of the Mesozoic due to the dominance of very large, visually oriented theropod dinosaurs [7]. Despite thyreophoran dinosaurs' possessing extensive dermal armor, some of the most extreme examples of anti-predator structures [8, 9], little direct evidence of predation on these and other dinosaur megaherbivores has been documented. Here we describe a new, exquisitely three-dimensionally preserved nodosaurid ankylosaur, Borealopelta markmitchelli gen. et sp. nov., from the Early Cretaceous of Alberta, which preserves integumentary structures as organic layers, including continuous fields of epidermal scales and intact horn sheaths capping the body armor. We identify melanin in the organic residues through mass spectroscopic analyses and observe lighter pigmentation of the large parascapular spines, consistent with display, and a pattern of countershading across the body. With an estimated body mass exceeding 1,300 kg, B. markmitchelli was much larger than modern terrestrial mammals that either are countershaded or experience significant predation pressure as adults. Presence of countershading suggests predation pressure strong enough to select for concealment in this megaherbivore despite possession of massive dorsal and lateral armor, illustrating a significant dichotomy between Mesozoic predator-prey dynamics and those of modern terrestrial systems.",
    url = "https://doi.org/10.1016/j.cub.2017.06.071",
    doi = "10.1016/j.cub.2017.06.071",
    openalex = "W2741141745",
    references = "doi101007s003590050286, doi101016jcub201606065, doi101016jpalaeo201602033, doi101016s0065345408601059, doi101017s0094837300005352, doi101017s0952836905007508, doi101038ncomms3827, doi101086668011, doi101111j10960031200800217x, doi101111j1469185x1993tb00738x, doi101371journalpbio1001853, doi101371journalpone0017932, doi101371journalpone0051925, doi105860choice273305, druckenmiller2010a, openalexw1528487914, openalexw3215057009, stevens2006binocular"
}

Ticks are currently among the most prevalent blood-feeding ectoparasites, but their feeding habits and hosts in deep time have long remained speculative. Here, we report direct and indirect evidence in 99 million-year-old Cretaceous amber showing that hard ticks and ticks of the extinct new family Deinocrotonidae fed on blood from feathered dinosaurs, non-avialan or avialan excluding crown-group birds. A †Cornupalpatum burmanicum hard tick is entangled in a pennaceous feather. Two deinocrotonids described as †Deinocroton draculi gen. et sp. nov. have specialised setae from dermestid beetle larvae (hastisetae) attached to their bodies, likely indicating cohabitation in a feathered dinosaur nest. A third conspecific specimen is blood-engorged, its anatomical features suggesting that deinocrotonids fed rapidly to engorgement and had multiple gonotrophic cycles. These findings provide insight into early tick evolution and ecology, and shed light on poorly known arthropod-vertebrate interactions and potential disease transmission during the Mesozoic.

@article{doi101038s4146701701550z,
    author = "Peñalver, Enrique and Arillo, Antonio and Delclòs, Xavier and Peris, David and Grimaldi, David A. and Anderson, Scott R. and Nascimbene, Paul C. and la Fuente, Ricardo Pérez‐de",
    title = "Ticks parasitised feathered dinosaurs as revealed by Cretaceous amber assemblages",
    year = "2017",
    journal = "Nature Communications",
    abstract = "Ticks are currently among the most prevalent blood-feeding ectoparasites, but their feeding habits and hosts in deep time have long remained speculative. Here, we report direct and indirect evidence in 99 million-year-old Cretaceous amber showing that hard ticks and ticks of the extinct new family Deinocrotonidae fed on blood from feathered dinosaurs, non-avialan or avialan excluding crown-group birds. A †Cornupalpatum burmanicum hard tick is entangled in a pennaceous feather. Two deinocrotonids described as †Deinocroton draculi gen. et sp. nov. have specialised setae from dermestid beetle larvae (hastisetae) attached to their bodies, likely indicating cohabitation in a feathered dinosaur nest. A third conspecific specimen is blood-engorged, its anatomical features suggesting that deinocrotonids fed rapidly to engorgement and had multiple gonotrophic cycles. These findings provide insight into early tick evolution and ecology, and shed light on poorly known arthropod-vertebrate interactions and potential disease transmission during the Mesozoic.",
    url = "https://doi.org/10.1038/s41467-017-01550-z",
    doi = "10.1038/s41467-017-01550-z",
    openalex = "W2768257042",
    references = "doi101038ncomms14972"
}

The titanosaurian sauropod dinosaur Mendozasaurus neguyelap is represented by several partial skeletons from a single locality within the Coniacian (lower Upper Cretaceous) Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina. A detailed revision of Mendozasaurus, including previously undocumented remains from the holotype site, allows us to more firmly establish its position within Titanosauria, as well as enabling an emended diagnosis of this taxon. Autapomorphies include: (1) middle and posterior cervical vertebrae with tall and transversely expanded neural spines that are wider than the centra, formed laterally by spinodiapophyseal laminae that are not connected with the pre- or postzygapophyses; (2) anterior caudal vertebrae (excluding anteriormost) with ventrolateral ridge-like expansion of prezygapophyses; and (3) humerus with divided lateral distal condyle on anterior surface. New remains demonstrate that the presacral vertebrae of Mendozasaurus were not unusually short anteroposteriorly, with this compression instead resulting from taphonomic crushing. Comparative studies of articulated pedes of other taxa allow us to interpret that the pedal formula of Mendozasaurus was 2-2-2-2-0, based on disarticulated bones that form a right hind foot. Mendozasaurus was incorporated into an expanded version of a titanosauriform-focussed phylogenetic data matrix, along with several other contemporaneous South American titanosaurs. The resultant data matrix comprises 84 taxa scored for 423 characters, and our phylogenetic analysis recovers Mendozasaurus as the most basal member of a diverse Lognkosauria, including Futalognkosaurus and the gigantic titanosaurs Argentinosaurus, Notocolossus, Patagotitan and Puertasaurus. Lognkosauria forms a clade with Rinconsauria (Muyelensaurus + Rinconsaurus), with Epachthosaurus and Pitekunsaurus recovered at the base of this grouping. A basal lithostrotian position for this South American clade is well supported, contrasting with some analyses that have placed these taxa outside of Lithostrotia or closer to Saltasauridae. The sister clade to this South American group is composed of an array of near-global taxa and supports the hypothesis that most titanosaurian clades were widespread by the Early-middle Cretaceous.

@article{doi101093zoolinneanzlx103,
    author = "Riga, Bernardo J. González and Mannion, Philip D. and Poropat, Stephen F. and David, Leonardo D. Ortiz and Coria, Juan Pedro",
    title = "Osteology of the Late Cretaceous Argentinean sauropod dinosaur Mendozasaurus neguyelap: implications for basal titanosaur relationships",
    year = "2017",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "The titanosaurian sauropod dinosaur Mendozasaurus neguyelap is represented by several partial skeletons from a single locality within the Coniacian (lower Upper Cretaceous) Sierra Barrosa Formation in the south of Mendoza Province, northern Neuquén Basin, Argentina. A detailed revision of Mendozasaurus, including previously undocumented remains from the holotype site, allows us to more firmly establish its position within Titanosauria, as well as enabling an emended diagnosis of this taxon. Autapomorphies include: (1) middle and posterior cervical vertebrae with tall and transversely expanded neural spines that are wider than the centra, formed laterally by spinodiapophyseal laminae that are not connected with the pre- or postzygapophyses; (2) anterior caudal vertebrae (excluding anteriormost) with ventrolateral ridge-like expansion of prezygapophyses; and (3) humerus with divided lateral distal condyle on anterior surface. New remains demonstrate that the presacral vertebrae of Mendozasaurus were not unusually short anteroposteriorly, with this compression instead resulting from taphonomic crushing. Comparative studies of articulated pedes of other taxa allow us to interpret that the pedal formula of Mendozasaurus was 2-2-2-2-0, based on disarticulated bones that form a right hind foot. Mendozasaurus was incorporated into an expanded version of a titanosauriform-focussed phylogenetic data matrix, along with several other contemporaneous South American titanosaurs. The resultant data matrix comprises 84 taxa scored for 423 characters, and our phylogenetic analysis recovers Mendozasaurus as the most basal member of a diverse Lognkosauria, including Futalognkosaurus and the gigantic titanosaurs Argentinosaurus, Notocolossus, Patagotitan and Puertasaurus. Lognkosauria forms a clade with Rinconsauria (Muyelensaurus + Rinconsaurus), with Epachthosaurus and Pitekunsaurus recovered at the base of this grouping. A basal lithostrotian position for this South American clade is well supported, contrasting with some analyses that have placed these taxa outside of Lithostrotia or closer to Saltasauridae. The sister clade to this South American group is composed of an array of near-global taxa and supports the hypothesis that most titanosaurian clades were widespread by the Early-middle Cretaceous.",
    url = "https://doi.org/10.1093/zoolinnean/zlx103",
    doi = "10.1093/zoolinnean/zlx103",
    openalex = "W2774005011",
    references = "doi101016jgr201403014, doi101016jjsames201411008, doi101038srep06196, doi101038srep19165, doi101038srep34467, doi101046j10963642200200029x, doi10108002724634199810011115, doi10108002724634199910011178, doi101098rspb20171219, doi101098rstb19950125, doi101111j10960031200800217x, doi101111j109636421998tb00569x, doi101371journalpone0125819, doi101525california97805202420980030015, doi1022179revmacn12239, doi1022179revmacn7344, doi1023073889325, doi102475ajss31695411, doi102475ajss319111253, doi105710amegh261210131889, doi107717peerj857"
}

The Late Jurassic to Early Cretaceous interval represents a time of environmental upheaval and cataclysmic events, combined with disruptions to terrestrial and marine ecosystems. Historically, the Jurassic/Cretaceous (J/K) boundary was classified as one of eight mass extinctions. However, more recent research has largely overturned this view, revealing a much more complex pattern of biotic and abiotic dynamics than has previously been appreciated. Here, we present a synthesis of our current knowledge of Late Jurassic-Early Cretaceous events, focusing particularly on events closest to the J/K boundary. We find evidence for a combination of short-term catastrophic events, large-scale tectonic processes and environmental perturbations, and major clade interactions that led to a seemingly dramatic faunal and ecological turnover in both the marine and terrestrial realms. This is coupled with a great reduction in global biodiversity which might in part be explained by poor sampling. Very few groups appear to have been entirely resilient to this J/K boundary 'event', which hints at a 'cascade model' of ecosystem changes driving faunal dynamics. Within terrestrial ecosystems, larger, more-specialised organisms, such as saurischian dinosaurs, appear to have suffered the most. Medium-sized tetanuran theropods declined, and were replaced by larger-bodied groups, and basal eusauropods were replaced by neosauropod faunas. The ascent of paravian theropods is emphasised by escalated competition with contemporary pterosaur groups, culminating in the explosive radiation of birds, although the timing of this is obfuscated by biases in sampling. Smaller, more ecologically diverse terrestrial non-archosaurs, such as lissamphibians and mammaliaforms, were comparatively resilient to extinctions, instead documenting the origination of many extant groups around the J/K boundary. In the marine realm, extinctions were focused on low-latitude, shallow marine shelf-dwelling faunas, corresponding to a significant eustatic sea-level fall in the latest Jurassic. More mobile and ecologically plastic marine groups, such as ichthyosaurs, survived the boundary relatively unscathed. High rates of extinction and turnover in other macropredaceous marine groups, including plesiosaurs, are accompanied by the origin of most major lineages of extant sharks. Groups which occupied both marine and terrestrial ecosystems, including crocodylomorphs, document a selective extinction in shallow marine forms, whereas turtles appear to have diversified. These patterns suggest that different extinction selectivity and ecological processes were operating between marine and terrestrial ecosystems, which were ultimately important in determining the fates of many key groups, as well as the origins of many major extant lineages. We identify a series of potential abiotic candidates for driving these patterns, including multiple bolide impacts, several episodes of flood basalt eruptions, dramatic climate change, and major disruptions to oceanic systems. The J/K transition therefore, although not a mass extinction, represents an important transitional period in the co-evolutionary history of life on Earth.

@article{doi101111brv12255,
    author = "Tennant, Jonathan P and Mannion, Philip D and Upchurch, Paul and Sutton, Mark D and Price, Gregory D",
    title = "Biotic and environmental dynamics through the Late Jurassic-Early Cretaceous transition: evidence for protracted faunal and ecological turnover.",
    year = "2017",
    journal = "Biological reviews of the Cambridge Philosophical Society",
    abstract = "The Late Jurassic to Early Cretaceous interval represents a time of environmental upheaval and cataclysmic events, combined with disruptions to terrestrial and marine ecosystems. Historically, the Jurassic/Cretaceous (J/K) boundary was classified as one of eight mass extinctions. However, more recent research has largely overturned this view, revealing a much more complex pattern of biotic and abiotic dynamics than has previously been appreciated. Here, we present a synthesis of our current knowledge of Late Jurassic-Early Cretaceous events, focusing particularly on events closest to the J/K boundary. We find evidence for a combination of short-term catastrophic events, large-scale tectonic processes and environmental perturbations, and major clade interactions that led to a seemingly dramatic faunal and ecological turnover in both the marine and terrestrial realms. This is coupled with a great reduction in global biodiversity which might in part be explained by poor sampling. Very few groups appear to have been entirely resilient to this J/K boundary 'event', which hints at a 'cascade model' of ecosystem changes driving faunal dynamics. Within terrestrial ecosystems, larger, more-specialised organisms, such as saurischian dinosaurs, appear to have suffered the most. Medium-sized tetanuran theropods declined, and were replaced by larger-bodied groups, and basal eusauropods were replaced by neosauropod faunas. The ascent of paravian theropods is emphasised by escalated competition with contemporary pterosaur groups, culminating in the explosive radiation of birds, although the timing of this is obfuscated by biases in sampling. Smaller, more ecologically diverse terrestrial non-archosaurs, such as lissamphibians and mammaliaforms, were comparatively resilient to extinctions, instead documenting the origination of many extant groups around the J/K boundary. In the marine realm, extinctions were focused on low-latitude, shallow marine shelf-dwelling faunas, corresponding to a significant eustatic sea-level fall in the latest Jurassic. More mobile and ecologically plastic marine groups, such as ichthyosaurs, survived the boundary relatively unscathed. High rates of extinction and turnover in other macropredaceous marine groups, including plesiosaurs, are accompanied by the origin of most major lineages of extant sharks. Groups which occupied both marine and terrestrial ecosystems, including crocodylomorphs, document a selective extinction in shallow marine forms, whereas turtles appear to have diversified. These patterns suggest that different extinction selectivity and ecological processes were operating between marine and terrestrial ecosystems, which were ultimately important in determining the fates of many key groups, as well as the origins of many major extant lineages. We identify a series of potential abiotic candidates for driving these patterns, including multiple bolide impacts, several episodes of flood basalt eruptions, dramatic climate change, and major disruptions to oceanic systems. The J/K transition therefore, although not a mass extinction, represents an important transitional period in the co-evolutionary history of life on Earth.",
    url = "https://pmc.ncbi.nlm.nih.gov/articles/PMC6849608/",
    doi = "10.1111/brv.12255",
    openalex = "W2283352195",
    pmcid = "PMC6849608",
    pmid = "26888552",
    references = "doi101007s1143001040949, doi1010160031018274900194, doi101016b9780444594259000263, doi101016jcretres201112005, doi101016jcretres201304001, doi101016jcub201408034, doi101016jearscirev201203002, doi101016jgloplacha201105009, doi101016s0009254199000819, doi101017s0016756812000994, doi1010291998rg000054, doi10102993rg02508, doi101038ncomms3827, doi101038ncomms7987, doi101038ncomms9438, doi101080027246342012694385, doi10108014772011003603556, doi101080147720192011630927, doi1010801477201920151059985, doi101086319243, doi101111brv12038, doi101111j1469185x200900107x, doi101111zoj12029, doi101126science1095964, doi101126science1116412, doi101126science1177265, doi101126science17540271199, doi101126science21545391501, doi101126science23547931156, doi101126scienceaaa3716, doi101144gslsp20032170111, doi101144sp35813, doi101371journalpone0029234, doi101371journalpone0103152, doi101371journalpone0112055, doi101371journalpone0125819, doi1016660022336020040780989dapftc20co2, doi1016660094837320000260056cefisg20co2, doi1026879529, doi103090610262296200073181198, doi104202app20110144"
}

Troodontids are known from Asia and North America, with the most complete specimens from the Jurassic of China and the Cretaceous of Mongolia. North American troodontids are poorly known, and specimens that have been described are isolated elements or partial skeletons with limited material. A new troodontid from the upper Dinosaur Park Formation (upper Campanian) is based on partial skulls, several vertebrae, ribs, gastralia, chevrons, a sacrum, partial pelvis, and partial fore and hind limbs. It is the largest troodontid known, with an estimated height of 180 cm and length of 350 cm. Like other troodontids, it possesses an elongated ambiens process and has a horizontal ventral margin of the postacetabular process. It differs from all other derived troodontids in that the slightly retroverted pubis has a shaft that curves anteroventrally. Some specimens from the Dinosaur Park Formation previously assigned to Troodon are reassigned to the new taxon, including multiple partial crania, an associated dentary and metatarsus, and a partial skeleton. Previously undescribed elements from the lower part of the Dinosaur Park Formation are assigned to the resurrected Stenonychosaurus inequalis. Distinct stratigraphic separation of Stenonychosaurus inequalis and the new taxon indicates a replacement in troodontid fauna, similar to the turnover of large ornithischians in the same formation. The new taxon is phylogenetically more closely related to Mongolian taxa, indicating the replacement of Stenonychosaurus may have been from an earlier Asian form immigrating into North America.

@article{doi101139cjes20170031,
    author = "van der Reest, Aaron J. and Currie, Philip J.",
    title = "Troodontids (Theropoda) from the Dinosaur Park Formation, Alberta, with a description of a unique new taxon: implications for deinonychosaur diversity in North America",
    year = "2017",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "Troodontids are known from Asia and North America, with the most complete specimens from the Jurassic of China and the Cretaceous of Mongolia. North American troodontids are poorly known, and specimens that have been described are isolated elements or partial skeletons with limited material. A new troodontid from the upper Dinosaur Park Formation (upper Campanian) is based on partial skulls, several vertebrae, ribs, gastralia, chevrons, a sacrum, partial pelvis, and partial fore and hind limbs. It is the largest troodontid known, with an estimated height of 180 cm and length of 350 cm. Like other troodontids, it possesses an elongated ambiens process and has a horizontal ventral margin of the postacetabular process. It differs from all other derived troodontids in that the slightly retroverted pubis has a shaft that curves anteroventrally. Some specimens from the Dinosaur Park Formation previously assigned to Troodon are reassigned to the new taxon, including multiple partial crania, an associated dentary and metatarsus, and a partial skeleton. Previously undescribed elements from the lower part of the Dinosaur Park Formation are assigned to the resurrected Stenonychosaurus inequalis. Distinct stratigraphic separation of Stenonychosaurus inequalis and the new taxon indicates a replacement in troodontid fauna, similar to the turnover of large ornithischians in the same formation. The new taxon is phylogenetically more closely related to Mongolian taxa, indicating the replacement of Stenonychosaurus may have been from an earlier Asian form immigrating into North America.",
    url = "https://doi.org/10.1139/cjes-2017-0031",
    doi = "10.1139/cjes-2017-0031",
    openalex = "W2742325356",
    references = "doi101007s0011401411439, doi101007s1143400900096, doi101016jpalaeo201206024, doi101016jpalaeo201206027, doi101038415780a, doi101038nature02898, doi101038ncomms4289, doi101038ncomms4788, doi1010800272463420161269539, doi101139e93187, doi1012066481, doi1012067481, doi101371journalpone0024487, doi101371journalpone0054329, doi101371journalpone0093190, doi1016710272463420072787antdtf20co2, doi105860choice435902, doi105962p339375, openalexw2597671315"
}

The Late Jurassic Tendaguru Formation of Tanzania, southeastern Africa, records a diverse and abundant sauropod fauna, including the flagellicaudatan diplodocoids Dicraeosaurus and Tornieria, and the brachiosaurid titanosauriform Giraffatitan. However, the taxonomic affinities of other sympatric sauropod taxa and remains are poorly understood. Here, we critically reassess and redescribe these problematic taxa, and present the largest phylogenetic analysis for sauropods (117 taxa scored for 542 characters) to explore their placement within Eusauropoda. A full re-description of the holotype of Janenschia, and all referable remains, supports its validity and placement as a nonneosauropod eusauropod. New information on the internal pneumatic tissue structure of the anterior dorsal vertebrae of the enigmatic Tendaguria tanzaniensis, coupled with a full re-description, results in its novel placement as a turiasaur. A previously referred caudal sequence cannot be assigned to Janenschia and displays several features that indicate a close relationship with Middle–Late Jurassic East Asian mamenchisaurids. It can be diagnosed by six autapomorphies, and we erect the new taxon Wamweracaudia keranjei n. gen. n. sp. The Tendaguru Formation shares representatives of nearly all sauropod lineages with Middle Jurassic–earliest Cretaceous global faunas, but displays a greater range of diversity than any of those faunas considered individually.

@article{doi101093zoolinneanzly068,
    author = "Mannion, Philip D. and Upchurch, Paul and Schwarz, Daniela and Wings, Oliver",
    title = "Taxonomic affinities of the putative titanosaurs from the Late Jurassic Tendaguru Formation of Tanzania: phylogenetic and biogeographic implications for eusauropod dinosaur evolution",
    year = "2018",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "The Late Jurassic Tendaguru Formation of Tanzania, southeastern Africa, records a diverse and abundant sauropod fauna, including the flagellicaudatan diplodocoids Dicraeosaurus and Tornieria, and the brachiosaurid titanosauriform Giraffatitan. However, the taxonomic affinities of other sympatric sauropod taxa and remains are poorly understood. Here, we critically reassess and redescribe these problematic taxa, and present the largest phylogenetic analysis for sauropods (117 taxa scored for 542 characters) to explore their placement within Eusauropoda. A full re-description of the holotype of Janenschia, and all referable remains, supports its validity and placement as a nonneosauropod eusauropod. New information on the internal pneumatic tissue structure of the anterior dorsal vertebrae of the enigmatic Tendaguria tanzaniensis, coupled with a full re-description, results in its novel placement as a turiasaur. A previously referred caudal sequence cannot be assigned to Janenschia and displays several features that indicate a close relationship with Middle–Late Jurassic East Asian mamenchisaurids. It can be diagnosed by six autapomorphies, and we erect the new taxon Wamweracaudia keranjei n. gen. n. sp. The Tendaguru Formation shares representatives of nearly all sauropod lineages with Middle Jurassic–earliest Cretaceous global faunas, but displays a greater range of diversity than any of those faunas considered individually.",
    url = "https://doi.org/10.1093/zoolinnean/zly068",
    doi = "10.1093/zoolinnean/zly068",
    openalex = "W2911482806",
    references = "doi101002mmng19994860020102, doi101002mmng19994860020109, doi101002mmng200900004, doi101016jcretres201603008, doi101016jearscirev201203002, doi101016jgr201403014, doi101017s0016756804000330, doi101038ncomms3929, doi101038s41467018051281, doi101038srep19165, doi101038srep34467, doi101080027246342011557116, doi101080027246342012671204, doi101080027246342013776562, doi101093sysbiosyu056, doi101093zoolinneanzlx103, doi101098rspb20120660, doi101098rspb20171219, doi101111cla12160, doi101111j10960031200800217x, doi101111j10963642201000620x, doi101111pala12142, doi101111zoj12029, doi101111zoj12425, doi101144001676492006032, doi101371journalpone0006924, doi101371journalpone0017114, doi101371journalpone0037122, doi101371journalpone0079420, doi101371journalpone0125819, doi1018814epiiugs2013v36i3002, doi1021425f55419694, doi1022179revmacn7344, doi1023073802723, doi1026879529, doi10274700206814489791, doi105281zenodo16171435, doi105710amegh261210131889, doi105860choice331556, doi107717peerj857, heinrich1998late, openalexw1545181283"
}

Abstract The Flat Rocks locality in the Wonthaggi Formation (Strzelecki Group) of the Gippsland Basin, southeastern Australia, hosts fossils of a late Barremian vertebrate fauna that inhabited the ancient rift between Australia and Antarctica. Known from its dentary, Qantassaurus intrepidus Rich and Vickers-Rich, 1999 has been the only dinosaur named from this locality. However, the plethora of vertebrate fossils collected from Flat Rocks suggests that further dinosaurs await discovery. From this locality, we name a new small-bodied ornithopod, Galleonosaurus dorisae n. gen. n. sp. from craniodental remains. Five ornithopodan genera are now named from Victoria. Galleonosaurus dorisae n. gen. n. sp. is known from five maxillae, from which the first description of jaw growth in an Australian dinosaur is provided. The holotype of Galleonosaurus dorisae n. gen. n. sp. is the most complete dinosaur maxilla known from Victoria. Micro-CT imagery of the holotype reveals the complex internal anatomy of the neurovascular tract and antorbital fossa. We confirm that Q. intrepidus is uniquely characterized by a deep foreshortened dentary. Two dentaries originally referred to Q. intrepidus are reassigned to Q.? intrepidus and a further maxilla is referred to cf. Atlascopcosaurus loadsi Rich and Rich, 1989. A further ornithopod dentary morphotype is identified, more elongate than those of Q. intrepidus and Q.? intrepidus and with three more tooth positions. This dentary might pertain to Galleonosaurus dorisae n. gen. n. sp. Phylogenetic analysis recovered Cretaceous Victorian and Argentinian nonstyracosternan ornithopods within the exclusively Gondwanan clade Elasmaria. However, the large-bodied taxon Muttaburrasaurus langdoni Bartholomai and Molnar, 1981 is hypothesised as a basal iguanodontian with closer affinities to dryomorphans than to rhabdodontids. UUID: http://zoobank.org/4af87bb4-b687-42f3-9622-aa806a6b4116

@article{doi101017jpa201895,
    author = "Herne, Matthew and Nair, Jay P. and Evans, Alistair R. and Tait, Alan",
    title = "New small-bodied ornithopods (Dinosauria, Neornithischia) from the Early Cretaceous Wonthaggi Formation (Strzelecki Group) of the Australian-Antarctic rift system, with revision of Qantassaurus intrepidus Rich and Vickers-Rich, 1999",
    year = "2019",
    journal = "Journal of Paleontology",
    abstract = "Abstract The Flat Rocks locality in the Wonthaggi Formation (Strzelecki Group) of the Gippsland Basin, southeastern Australia, hosts fossils of a late Barremian vertebrate fauna that inhabited the ancient rift between Australia and Antarctica. Known from its dentary, Qantassaurus intrepidus Rich and Vickers-Rich, 1999 has been the only dinosaur named from this locality. However, the plethora of vertebrate fossils collected from Flat Rocks suggests that further dinosaurs await discovery. From this locality, we name a new small-bodied ornithopod, Galleonosaurus dorisae n. gen. n. sp. from craniodental remains. Five ornithopodan genera are now named from Victoria. Galleonosaurus dorisae n. gen. n. sp. is known from five maxillae, from which the first description of jaw growth in an Australian dinosaur is provided. The holotype of Galleonosaurus dorisae n. gen. n. sp. is the most complete dinosaur maxilla known from Victoria. Micro-CT imagery of the holotype reveals the complex internal anatomy of the neurovascular tract and antorbital fossa. We confirm that Q. intrepidus is uniquely characterized by a deep foreshortened dentary. Two dentaries originally referred to Q. intrepidus are reassigned to Q.? intrepidus and a further maxilla is referred to cf. Atlascopcosaurus loadsi Rich and Rich, 1989. A further ornithopod dentary morphotype is identified, more elongate than those of Q. intrepidus and Q.? intrepidus and with three more tooth positions. This dentary might pertain to Galleonosaurus dorisae n. gen. n. sp. Phylogenetic analysis recovered Cretaceous Victorian and Argentinian nonstyracosternan ornithopods within the exclusively Gondwanan clade Elasmaria. However, the large-bodied taxon Muttaburrasaurus langdoni Bartholomai and Molnar, 1981 is hypothesised as a basal iguanodontian with closer affinities to dryomorphans than to rhabdodontids. UUID: http://zoobank.org/4af87bb4-b687-42f3-9622-aa806a6b4116",
    url = "https://doi.org/10.1017/jpa.2018.95",
    doi = "10.1017/jpa.2018.95",
    openalex = "W2921822738",
    references = "doi101080027246342012694385, doi101080027246342013746229, doi1010800272463420161269539, doi1010800311551820181453085, doi1010801477201920171371258, doi101111j10963642201000620x, doi101111pala12236, doi102307jctt1zxz1md6, doi102307jctvxkn7tk, doi105860choice503272, doi107717peerj1523, openalexw575814759"
}

Titanosaurs were a globally distributed clade of Cretaceous sauropods. Historically regarded as a primarily Gondwanan radiation, there is a growing number of Eurasian taxa, with several putative titanosaurs contemporaneous with, or even pre-dating, the oldest known Southern Hemisphere remains. The early Late Cretaceous Jinhua Formation, in Zhejiang Province, China, has yielded two putative titanosaurs, Jiangshanosaurus lixianensis and Dongyangosaurus sinensis. Here, we provide a detailed re-description and diagnosis of Jiangshanosaurus, as well as new anatomical information on Dongyangosaurus. Previously, a 'derived' titanosaurian placement for Jiangshanosaurus was primarily based on the presence of procoelous anterior caudal centra. We show that this taxon had amphicoelous anterior-middle caudal centra. Its only titanosaurian synapomorphy is that the dorsal margins of the scapula and coracoid are approximately level with one another. Dongyangosaurus can clearly be differentiated from Jiangshanosaurus, and displays features that indicate a closer relationship to the titanosaur radiation. Revised scores for both taxa are incorporated into an expanded phylogenetic data matrix, comprising 124 taxa scored for 548 characters. Under equal weights parsimony, Jiangshanosaurus is recovered as a member of the non-titanosaurian East Asian somphospondylan clade Euhelopodidae, and Dongyangosaurus lies just outside of Titanosauria. However, when extended implied weighting is applied, both taxa are placed within Titanosauria. Most other 'middle' Cretaceous East Asian sauropods are probably non-titanosaurian somphospondylans, but at least Xianshanosaurus appears to belong to the titanosaur radiation. Our analyses also recover the Early Cretaceous European sauropod Normanniasaurus genceyi as a 'derived' titanosaur, clustering with Gondwanan taxa. These results provide further support for a widespread diversification of titanosaurs by at least the Early Cretaceous.

@article{doi101098rsos191057,
    author = "Mannion, Philip D. and Upchurch, Paul and Jin, Xingsheng and Zheng, Wenjie",
    title = "New information on the Cretaceous sauropod dinosaurs of Zhejiang Province, China: impact on Laurasian titanosauriform phylogeny and biogeography",
    year = "2019",
    journal = "Royal Society Open Science",
    abstract = "Titanosaurs were a globally distributed clade of Cretaceous sauropods. Historically regarded as a primarily Gondwanan radiation, there is a growing number of Eurasian taxa, with several putative titanosaurs contemporaneous with, or even pre-dating, the oldest known Southern Hemisphere remains. The early Late Cretaceous Jinhua Formation, in Zhejiang Province, China, has yielded two putative titanosaurs, Jiangshanosaurus lixianensis and Dongyangosaurus sinensis. Here, we provide a detailed re-description and diagnosis of Jiangshanosaurus, as well as new anatomical information on Dongyangosaurus. Previously, a 'derived' titanosaurian placement for Jiangshanosaurus was primarily based on the presence of procoelous anterior caudal centra. We show that this taxon had amphicoelous anterior-middle caudal centra. Its only titanosaurian synapomorphy is that the dorsal margins of the scapula and coracoid are approximately level with one another. Dongyangosaurus can clearly be differentiated from Jiangshanosaurus, and displays features that indicate a closer relationship to the titanosaur radiation. Revised scores for both taxa are incorporated into an expanded phylogenetic data matrix, comprising 124 taxa scored for 548 characters. Under equal weights parsimony, Jiangshanosaurus is recovered as a member of the non-titanosaurian East Asian somphospondylan clade Euhelopodidae, and Dongyangosaurus lies just outside of Titanosauria. However, when extended implied weighting is applied, both taxa are placed within Titanosauria. Most other 'middle' Cretaceous East Asian sauropods are probably non-titanosaurian somphospondylans, but at least Xianshanosaurus appears to belong to the titanosaur radiation. Our analyses also recover the Early Cretaceous European sauropod Normanniasaurus genceyi as a 'derived' titanosaur, clustering with Gondwanan taxa. These results provide further support for a widespread diversification of titanosaurs by at least the Early Cretaceous.",
    url = "https://doi.org/10.1098/rsos.191057",
    doi = "10.1098/rsos.191057",
    openalex = "W2970495169",
    references = "doi101016jcretres201603008, doi101016jgr201403014, doi101016jjsames201411008, doi101016jpalaeo201206008, doi101038srep34467, doi101080027246342012671204, doi101093zoolinneanzlx103, doi101093zoolinneanzly068, doi101098rspb20171219, doi101111brv12255, doi1011646zootaxa384811, doi101371journalpone0125819, doi103897zookeys4698439"
}

ABSTRACT Microbially induced sedimentary structures may help preserve unique glimpses of ancient shoreline habitats, but are little known from Mesozoic epicontinental settings. To help fill this knowledge gap, we describe a diverse suite of microbial structures from the Upper Cretaceous “J” Sandstone (South Platte Formation, Dakota Group) that are spectacularly exposed at Dinosaur Ridge in Morrison, Colorado, USA. Structures include “tattered” bed surfaces and ferruginous sand chips in supratidal flat facies. A large over-flip structure is preserved in a channel locally known as Crocodile Creek. In upper-intertidal facies, multidirectional ripple marks occur. Perhaps the most well-known microbial structures are exposed on extensive bedding surfaces known as “Slimy Beach,” where lower supratidal-flat facies are dominated by decimeter-scale erosional remnants and pockets. Morphologies and superposition of the structures allows identification of three generations of erosional pockets. Generation A of these erosional pockets exhibit size similarities to ornithomimid, sauropod, and ornithopod dinosaur tracks from adjacent bedding planes, raising the question of whether initial disturbance of the mat-bound surface could have been from track making. Generation B erosional pockets are older and record continuous erosion of the initial pockets until they were eventually overgrown and sealed by microbial mats. Generation C pockets are the oldest ones, exposing wide areas of barren sediment that could not be overgrown by microbial mats anymore. In concert, the microbial structures point to seasonally variable meteorological conditions along the coastline of the Western Interior Seaway and indicate that the “Slimy Beach” bedding plane represents a multi-year record of dinosaur locomotion.

@article{doi102110jsr201957,
    author = "Noffke, Nora and Hagadorn, James W. and Bartlett, Sam",
    title = "Microbial structures and dinosaur trackways from a Cretaceous coastal environment (Dakota Group, Colorado, U.S.A.)",
    year = "2019",
    journal = "Journal of Sedimentary Research",
    abstract = "ABSTRACT Microbially induced sedimentary structures may help preserve unique glimpses of ancient shoreline habitats, but are little known from Mesozoic epicontinental settings. To help fill this knowledge gap, we describe a diverse suite of microbial structures from the Upper Cretaceous “J” Sandstone (South Platte Formation, Dakota Group) that are spectacularly exposed at Dinosaur Ridge in Morrison, Colorado, USA. Structures include “tattered” bed surfaces and ferruginous sand chips in supratidal flat facies. A large over-flip structure is preserved in a channel locally known as Crocodile Creek. In upper-intertidal facies, multidirectional ripple marks occur. Perhaps the most well-known microbial structures are exposed on extensive bedding surfaces known as “Slimy Beach,” where lower supratidal-flat facies are dominated by decimeter-scale erosional remnants and pockets. Morphologies and superposition of the structures allows identification of three generations of erosional pockets. Generation A of these erosional pockets exhibit size similarities to ornithomimid, sauropod, and ornithopod dinosaur tracks from adjacent bedding planes, raising the question of whether initial disturbance of the mat-bound surface could have been from track making. Generation B erosional pockets are older and record continuous erosion of the initial pockets until they were eventually overgrown and sealed by microbial mats. Generation C pockets are the oldest ones, exposing wide areas of barren sediment that could not be overgrown by microbial mats anymore. In concert, the microbial structures point to seasonally variable meteorological conditions along the coastline of the Western Interior Seaway and indicate that the “Slimy Beach” bedding plane represents a multi-year record of dinosaur locomotion.",
    url = "https://doi.org/10.2110/jsr.2019.57",
    doi = "10.2110/jsr.2019.57",
    openalex = "W2989574286",
    references = "doi101016jearscirev200810005, doi101016jjmarsys200405013, doi101016s0037073800000981, doi101038srep18952, doi101046j13653091200000284x, doi10108008912960903503345, doi10108010420940802471027, doi101111j13653091201101278x, doi101146annurevearth271313, doi101371journalpone0126946, openalexw431002082"
}

The first fossil remains of vertebrates, invertebrates, plants and palynomorphs of the Chorrillo Formation (Austral Basin), about 30km to the SW of the town of El Calafate (Province of Santa Cruz), are described. Fossils include the elasmarian (basal Iguanodontia) Isasicursor santacrucensis gen. et sp. nov., the large titanosaur Nullotitan glaciaris gen. et sp. nov., both large and small Megaraptoridae indet., and fragments of sauropod and theropod eggshells. The list of vertebrates is also composed by the Neognathae Kookne yeutensis gen. et sp. nov., two isolated caudal vertebrae of Mammalia indet., and isolated teeth of a large mosasaur. Remains of fishes, anurans, turtles, and snakes are represented by fragmentary material of low taxonomical value, with the exception of remains belonging to Calyptocephalellidae. On the other hand, a remarkable diversity of terrestrial and freshwater gastropods has been documented, as well as fossil woods and palinological assemblages. The Chorrillo Formation continues south, in the Las Chinas River valley, southern Chile, where it is called Dorotea Formation. Both units share in their lower two thirds abundant materials of titanosaurs, whose remains cease to appear in the upper third, registering only elasmarians (Chorrillo Formation) and hadrosaurs (Dorotea Formation). Above both units there are levels with remains of invertebrates and marine reptiles. It is striking that the dinosaurs of the lower two thirds of the Chorrillo and Dorotea formations are represented by large basal titanosaurs and Megaraptoridae coelurosaurs, being the Saltasaurinae and Aeolosaurinae sauropods and Abelisauridae theropods totally absent. In contrast, these taxa are dominant components in sedimentary units of central and northern Patagonia (e.g., Allen, Los Alamitos, La Colonia formations). Such differences could reflect, in part, a greater antiquity (i.e., late Campanian-early Maastrichtian) for the Chorrillo fossils, or, more probably, different environmental conditions. Thus, knowledge of the biota of the southern tip of Patagonia is expanded, particularly those temporarily close to the K-Pg boundary.

@article{doi1022179revmacn21655,
    author = "Novas, Fernando E. and Agnolín, Federico L. and Rozadilla, Sebastián and Aranciaga-Rolando, Alexis Mauro and Brissón-Eli, Federico and Motta, Matías J. and Cerroni, Mauricio A. and Ezcurra, Martín D. and Martinelli, Agustín G. and ́Angelo, Julia D and Álvarez-Herrera, Gerardo P. and Gentil, Adriel R. and Bogan, Sergio and Chimento, Nicolás R. and Garcia-Marsà, Jordi A. and Coco, Gastón Lo and Miquel, Sergio E. and Brito, Fátima and Vera, Ezequiel I. and Loinaze, Valeria S. Pérez and Fernández, Mariela Soledad and Salgado, Leonardo",
    title = "Paleontological discoveries in the Chorrillo Formation (upper Campanian-lower Maastrichtian, Upper Cretaceous), Santa Cruz Province, Patagonia, Argentina",
    year = "2019",
    journal = "Revista del Museo Argentino de Ciencias Naturales",
    abstract = "The first fossil remains of vertebrates, invertebrates, plants and palynomorphs of the Chorrillo Formation (Austral Basin), about 30km to the SW of the town of El Calafate (Province of Santa Cruz), are described. Fossils include the elasmarian (basal Iguanodontia) Isasicursor santacrucensis gen. et sp. nov., the large titanosaur Nullotitan glaciaris gen. et sp. nov., both large and small Megaraptoridae indet., and fragments of sauropod and theropod eggshells. The list of vertebrates is also composed by the Neognathae Kookne yeutensis gen. et sp. nov., two isolated caudal vertebrae of Mammalia indet., and isolated teeth of a large mosasaur. Remains of fishes, anurans, turtles, and snakes are represented by fragmentary material of low taxonomical value, with the exception of remains belonging to Calyptocephalellidae. On the other hand, a remarkable diversity of terrestrial and freshwater gastropods has been documented, as well as fossil woods and palinological assemblages. The Chorrillo Formation continues south, in the Las Chinas River valley, southern Chile, where it is called Dorotea Formation. Both units share in their lower two thirds abundant materials of titanosaurs, whose remains cease to appear in the upper third, registering only elasmarians (Chorrillo Formation) and hadrosaurs (Dorotea Formation). Above both units there are levels with remains of invertebrates and marine reptiles. It is striking that the dinosaurs of the lower two thirds of the Chorrillo and Dorotea formations are represented by large basal titanosaurs and Megaraptoridae coelurosaurs, being the Saltasaurinae and Aeolosaurinae sauropods and Abelisauridae theropods totally absent. In contrast, these taxa are dominant components in sedimentary units of central and northern Patagonia (e.g., Allen, Los Alamitos, La Colonia formations). Such differences could reflect, in part, a greater antiquity (i.e., late Campanian-early Maastrichtian) for the Chorrillo fossils, or, more probably, different environmental conditions. Thus, knowledge of the biota of the southern tip of Patagonia is expanded, particularly those temporarily close to the K-Pg boundary.",
    url = "https://doi.org/10.22179/revmacn.21.655",
    doi = "10.22179/revmacn.21.655",
    openalex = "W2993538476",
    references = "doi101016jcretres200806007, doi101016jrevpalbo200709004, doi101038s41598019453069, doi101038srep06196, doi101093zoolinneanzlx103, doi101098rspb20171219, doi101371journalpone0044318"
}

@book{doi102307jctvqc6gzx,
    author = "OSTROM, JOHN H.",
    title = "Osteology of Deinonychus antirrhopus, an Unusual Theropod from the Lower Cretaceous of Montana",
    year = "2019",
    booktitle = "Yale University Press eBooks",
    url = "https://doi.org/10.2307/j.ctvqc6gzx",
    doi = "10.2307/j.ctvqc6gzx",
    openalex = "W4245768089"
}

@misc{ostrom2019osteology,
    author = "Ostrom, John H.",
    title = "Osteology of Deinonychus antirrhopus, an Unusual Theropod from the Lower Cretaceous of Montana",
    year = "2019",
    url = "https://doi.org/10.12987/9781933789408",
    doi = "10.12987/9781933789408"
}

Abstract The titanosaurian sauropod dinosaur Diamantinasaurus matildae is represented by two individuals from the Cenomanian–lower Turonian ‘upper’ Winton Formation of central Queensland, north-eastern Australia. The type specimen has been described in detail, whereas the referred specimen, which includes several elements not present in the type series (partial skull, atlas, axis and postaxial cervical vertebrae), has only been described briefly. Herein, we provide a comprehensive description of this referred specimen, including a thorough assessment of the external and internal anatomy of the braincase, and identify several new autapomorphies of D. matildae. Via an expanded data matrix consisting of 125 taxa scored for 552 characters, we recover a close, well-supported relationship between Diamantinasaurus and its contemporary, Savannasaurus elliottorum. Unlike previous iterations of this data matrix, under a parsimony framework we consistently recover Diamantinasaurus and Savannasaurus as early-diverging members of Titanosauria using both equal weighting and extended implied weighting, with the overall topology largely consistent between analyses. We erect a new clade, named Diamantinasauria herein, that also includes the contemporaneous Sarmientosaurus musacchioi from southern Argentina, which shares several cranial features with the referred Diamantinasaurus specimen. Thus, Diamantinasauria is represented in the mid-Cretaceous of both South America and Australia, supporting the hypothesis that some titanosaurians, in addition to megaraptoran theropods and possibly some ornithopods, were able to disperse between these two continents via Antarctica. Conversely, there is no evidence for rebbachisaurids in Australia, which might indicate that they were unable to expand into high latitudes before their extinction in the Cenomanian–Turonian. Likewise, there is no evidence for titanosaurs with procoelous caudal vertebrae in the mid-Cretaceous Australian record, despite scarce but compelling evidence for their presence in both Antarctica and New Zealand during the Campanian–Maastrichtian. These later titanosaurs presumably dispersed into these landmasses from South America before the Campanian (~85 Mya), when seafloor spreading between Zealandia and Australia commenced. Although Australian mid-Cretaceous dinosaur faunas appear to be cosmopolitan at higher taxonomic levels, closer affinities with South America at finer scales are becoming better supported for sauropods, theropods and ornithopods.

@article{doi101093zoolinneanzlaa173,
    author = "Poropat, Stephen F. and Kundrát, Martin and Mannion, Philip D. and Upchurch, Paul and Tischler, Travis R. and Elliott, David A.",
    title = "Second specimen of the Late Cretaceous Australian sauropod dinosaur Diamantinasaurus matildae provides new anatomical information on the skull and neck of early titanosaurs",
    year = "2020",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "Abstract The titanosaurian sauropod dinosaur Diamantinasaurus matildae is represented by two individuals from the Cenomanian–lower Turonian ‘upper’ Winton Formation of central Queensland, north-eastern Australia. The type specimen has been described in detail, whereas the referred specimen, which includes several elements not present in the type series (partial skull, atlas, axis and postaxial cervical vertebrae), has only been described briefly. Herein, we provide a comprehensive description of this referred specimen, including a thorough assessment of the external and internal anatomy of the braincase, and identify several new autapomorphies of D. matildae. Via an expanded data matrix consisting of 125 taxa scored for 552 characters, we recover a close, well-supported relationship between Diamantinasaurus and its contemporary, Savannasaurus elliottorum. Unlike previous iterations of this data matrix, under a parsimony framework we consistently recover Diamantinasaurus and Savannasaurus as early-diverging members of Titanosauria using both equal weighting and extended implied weighting, with the overall topology largely consistent between analyses. We erect a new clade, named Diamantinasauria herein, that also includes the contemporaneous Sarmientosaurus musacchioi from southern Argentina, which shares several cranial features with the referred Diamantinasaurus specimen. Thus, Diamantinasauria is represented in the mid-Cretaceous of both South America and Australia, supporting the hypothesis that some titanosaurians, in addition to megaraptoran theropods and possibly some ornithopods, were able to disperse between these two continents via Antarctica. Conversely, there is no evidence for rebbachisaurids in Australia, which might indicate that they were unable to expand into high latitudes before their extinction in the Cenomanian–Turonian. Likewise, there is no evidence for titanosaurs with procoelous caudal vertebrae in the mid-Cretaceous Australian record, despite scarce but compelling evidence for their presence in both Antarctica and New Zealand during the Campanian–Maastrichtian. These later titanosaurs presumably dispersed into these landmasses from South America before the Campanian (\textasciitilde 85 Mya), when seafloor spreading between Zealandia and Australia commenced. Although Australian mid-Cretaceous dinosaur faunas appear to be cosmopolitan at higher taxonomic levels, closer affinities with South America at finer scales are becoming better supported for sauropods, theropods and ornithopods.",
    url = "https://doi.org/10.1093/zoolinnean/zlaa173",
    doi = "10.1093/zoolinnean/zlaa173",
    openalex = "W3124534006",
    references = "doi101016jgr201403014, doi101016jjsames2019102460, doi101038s41467018051281, doi101038s41598020576677, doi101038srep34467, doi101080027246342013776562, doi1010800272463420161269539, doi1010800311551820181453085, doi1010800891296320201793979, doi101093zoolinneanzlx103, doi101093zoolinneanzly068, doi1011646zootaxa370131, doi1011646zootaxa384811, doi101371journalpone0030060, doi101371journalpone0054991, doi101371journalpone0151661, doi1029920070860302, doi105710amegh261210131889, openalexw3015256845"
}

The independent evolution of gigantism among dinosaurs has been a topic of long-standing interest, but it remains unclear if gigantic theropods, the largest bipeds in the fossil record, all achieved massive sizes in the same manner, or through different strategies. We perform multi-element histological analyses on a phylogenetically broad dataset sampled from eight theropod families, with a focus on gigantic tyrannosaurids and carcharodontosaurids, to reconstruct the growth strategies of these lineages and test if particular bones consistently preserve the most complete growth record. We find that in skeletally mature gigantic theropods, weight-bearing bones consistently preserve extensive growth records, whereas non-weight-bearing bones are remodelled and less useful for growth reconstruction, contrary to the pattern observed in smaller theropods and some other dinosaur clades. We find a heterochronic pattern of growth fitting an acceleration model in tyrannosaurids, with allosauroid carcharodontosaurids better fitting a model of hypermorphosis. These divergent growth patterns appear phylogenetically constrained, representing extreme versions of the growth patterns present in smaller coelurosaurs and allosauroids, respectively. This provides the first evidence of a lack of strong mechanistic or physiological constraints on size evolution in the largest bipeds in the fossil record and evidence of one of the longest-living individual dinosaurs ever documented.

@article{doi101098rspb20202258,
    author = "Cullen, Thomas M. and Canale, Juan I. and Apesteguı́a, Sebastián and Smith, Nathan D. and Hu, Dongyu and Makovicky, Peter J.",
    title = "Osteohistological analyses reveal diverse strategies of theropod dinosaur body-size evolution",
    year = "2020",
    journal = "Proceedings of the Royal Society B Biological Sciences",
    abstract = "The independent evolution of gigantism among dinosaurs has been a topic of long-standing interest, but it remains unclear if gigantic theropods, the largest bipeds in the fossil record, all achieved massive sizes in the same manner, or through different strategies. We perform multi-element histological analyses on a phylogenetically broad dataset sampled from eight theropod families, with a focus on gigantic tyrannosaurids and carcharodontosaurids, to reconstruct the growth strategies of these lineages and test if particular bones consistently preserve the most complete growth record. We find that in skeletally mature gigantic theropods, weight-bearing bones consistently preserve extensive growth records, whereas non-weight-bearing bones are remodelled and less useful for growth reconstruction, contrary to the pattern observed in smaller theropods and some other dinosaur clades. We find a heterochronic pattern of growth fitting an acceleration model in tyrannosaurids, with allosauroid carcharodontosaurids better fitting a model of hypermorphosis. These divergent growth patterns appear phylogenetically constrained, representing extreme versions of the growth patterns present in smaller coelurosaurs and allosauroids, respectively. This provides the first evidence of a lack of strong mechanistic or physiological constraints on size evolution in the largest bipeds in the fossil record and evidence of one of the longest-living individual dinosaurs ever documented.",
    url = "https://doi.org/10.1098/rspb.2020.2258",
    doi = "10.1098/rspb.2020.2258",
    openalex = "W3110230871",
    references = "doi101016jcub201408034, doi101017s0094837300006588, doi101017s0094837300021308, doi101029sc005p0175, doi101038nature02699, doi101038ncomms3827, doi101073pnas0708903105, doi101098rspb20122526, doi101126sciadvaax6250, doi101126science1225376, doi101126science1258750, doi101146annurevearth060313054858, doi101186174170071060, doi101186s1289801601068, doi101371journalpone0033539, doi1016710272463420000200115lbhoth20co2, doi10560219780801881206, doi105860choice490282, erickson2014on"
}

Pittman, Michael, Xu, Xing (2020): Pennaraptoran Theropod Dinosaurs Past Progress And New Frontiers. Bulletin of the American Museum of Natural History 2020 (440): 1-353, DOI: 10.1206/0003-0090.440.1.1, URL: https://doi.org/10.1206/0003-0090.440.1.1

@article{doi1012060003009044011,
    author = "Pittman, Michael and Xu, Xing",
    title = "Pennaraptoran Theropod Dinosaurs Past Progress and New Frontiers",
    year = "2020",
    journal = "Bulletin of the American Museum of Natural History",
    abstract = "Pittman, Michael, Xu, Xing (2020): Pennaraptoran Theropod Dinosaurs Past Progress And New Frontiers. Bulletin of the American Museum of Natural History 2020 (440): 1-353, DOI: 10.1206/0003-0090.440.1.1, URL: https://doi.org/10.1206/0003-0090.440.1.1",
    url = "https://doi.org/10.1206/0003-0090.440.1.1",
    doi = "10.1206/0003-0090.440.1.1",
    openalex = "W3000686130",
    references = "cau2018redescription, doi101002ar24241, doi101007s0011401209171, doi101007s0011401311075, doi101007s0011401411439, doi101016jcretres200806007, doi101016jcub201508003, doi101016jcub201804062, doi101016jcub202006105, doi101016jjsames201810005, doi101016jpalaeo201206027, doi101017njg201815, doi1010292018gc007584, doi101038nature13467, doi101038nature14423, doi101038nature19417, doi101038nature24679, doi101038ncomms14972, doi101038s4146701909259x, doi101073pnas1006970107, doi101073pnas1813206116, doi101080027246342012717567, doi101080027246342012719176, doi101080147720192010488045, doi101098rsbl20060523, doi101111cla12160, doi101111evo12150, doi101111j109600311993tb00209x, doi101111j109600311999tb00278x, doi101111j10960031200800217x, doi101111j109636421978tb01049x, doi101126science1126377, doi101126science1157704, doi101126science1253451, doi101127njgpm19821982440, doi101139cjes20170031, doi101139cjes20170034, doi101144001676492006032, doi101371journalpone0014329, doi101371journalpone0036790, doi101371journalpone0080557, doi101371journalpone0092022, doi101371journalpone0112055, doi101371journalpone0126791, doi1015468gcrned, doi10159023174889201500020001, doi101590s000137652011000100008, doi1016660022336020010750208lcsdaf20co2, doi10166613052, doi1016710272463420050250897anotmf20co2, doi1016710272463420072787antdtf20co2, doi1017161paleo180818764, doi1022179revmacn12239, doi1022179revmacn8325, doi1033740140540102, doi103389feart201800252, doi105281zenodo16171435, doi105962p339375, doi107717peerj1032, doi107717peerj2159, doi107717peerj4558, doi107717peerj7247, lee2019a, longrich2008a, osmólska1982hulsanpes, sues1978a, xu2010a"
}

Limb length, cursoriality and speed have long been areas of significant interest in theropod paleobiology, since locomotory capacity, especially running ability, is critical in the pursuit of prey and to avoid becoming prey. The impact of allometry on running ability, and the limiting effect of large body size, are aspects that are traditionally overlooked. Since several different non-avian theropod lineages have each independently evolved body sizes greater than any known terrestrial carnivorous mammal, ~1000kg or more, the effect that such large mass has on movement ability and energetics is an area with significant implications for Mesozoic paleoecology. Here, using expansive datasets that incorporate several different metrics to estimate body size, limb length and running speed, we calculate the effects of allometry on running ability. We test traditional metrics used to evaluate cursoriality in non-avian theropods such as distal limb length, relative hindlimb length, and compare the energetic cost savings of relative hindlimb elongation between members of the Tyrannosauridae and more basal megacarnivores such as Allosauroidea or Ceratosauridae. We find that once the limiting effects of body size increase is incorporated there is no significant correlation to top speed between any of the commonly used metrics, including the newly suggested distal limb index (Tibia + Metatarsus/ Femur length). The data also shows a significant split between large and small bodied theropods in terms of maximizing running potential suggesting two distinct strategies for promoting limb elongation based on the organisms' size. For small and medium sized theropods increased leg length seems to correlate with a desire to increase top speed while amongst larger taxa it corresponds more closely to energetic efficiency and reducing foraging costs. We also find, using 3D volumetric mass estimates, that the Tyrannosauridae show significant cost of transport savings compared to more basal clades, indicating reduced energy expenditures during foraging and likely reduced need for hunting forays. This suggests that amongst theropods, hindlimb evolution was not dictated by one particular strategy. Amongst smaller bodied taxa the competing pressures of being both a predator and a prey item dominant while larger ones, freed from predation pressure, seek to maximize foraging ability. We also discuss the implications both for interactions amongst specific clades and Mesozoic paleobiology and paleoecological reconstructions as a whole.

@article{doi101371journalpone0223698,
    author = "Dececchi, T. Alexander and Mloszewska, Aleksandra M. and Holtz, Thomas R. and Habib, Michael and Larsson, Hans C. E.",
    title = "The fast and the frugal: Divergent locomotory strategies drive limb lengthening in theropod dinosaurs",
    year = "2020",
    journal = "PLoS ONE",
    abstract = "Limb length, cursoriality and speed have long been areas of significant interest in theropod paleobiology, since locomotory capacity, especially running ability, is critical in the pursuit of prey and to avoid becoming prey. The impact of allometry on running ability, and the limiting effect of large body size, are aspects that are traditionally overlooked. Since several different non-avian theropod lineages have each independently evolved body sizes greater than any known terrestrial carnivorous mammal, \textasciitilde 1000kg or more, the effect that such large mass has on movement ability and energetics is an area with significant implications for Mesozoic paleoecology. Here, using expansive datasets that incorporate several different metrics to estimate body size, limb length and running speed, we calculate the effects of allometry on running ability. We test traditional metrics used to evaluate cursoriality in non-avian theropods such as distal limb length, relative hindlimb length, and compare the energetic cost savings of relative hindlimb elongation between members of the Tyrannosauridae and more basal megacarnivores such as Allosauroidea or Ceratosauridae. We find that once the limiting effects of body size increase is incorporated there is no significant correlation to top speed between any of the commonly used metrics, including the newly suggested distal limb index (Tibia + Metatarsus/ Femur length). The data also shows a significant split between large and small bodied theropods in terms of maximizing running potential suggesting two distinct strategies for promoting limb elongation based on the organisms' size. For small and medium sized theropods increased leg length seems to correlate with a desire to increase top speed while amongst larger taxa it corresponds more closely to energetic efficiency and reducing foraging costs. We also find, using 3D volumetric mass estimates, that the Tyrannosauridae show significant cost of transport savings compared to more basal clades, indicating reduced energy expenditures during foraging and likely reduced need for hunting forays. This suggests that amongst theropods, hindlimb evolution was not dictated by one particular strategy. Amongst smaller bodied taxa the competing pressures of being both a predator and a prey item dominant while larger ones, freed from predation pressure, seek to maximize foraging ability. We also discuss the implications both for interactions amongst specific clades and Mesozoic paleobiology and paleoecological reconstructions as a whole.",
    url = "https://doi.org/10.1371/journal.pone.0223698",
    doi = "10.1371/journal.pone.0223698",
    openalex = "W3025614156",
    references = "doi101038s4155901908880, doi107717peerj885"
}

embryos are remarkably rare. Here we report an exceptionally preserved, articulated oviraptorid embryo inside an elongatoolithid egg, from the Late Cretaceous Hekou Formation of southern China. The head lies ventral to the body, with the feet on either side, and the back curled along the blunt pole of the egg, in a posture previously unrecognized in a non-avian dinosaur, but reminiscent of a late-stage modern bird embryo. Comparison to other late-stage oviraptorid embryos suggests that prehatch oviraptorids developed avian-like postures late in incubation, which in modern birds are related to coordinated embryonic movements associated with tucking - a behavior controlled by the central nervous system, critical for hatching success. We propose that such pre-hatching behavior, previously considered unique to birds, may have originated among non-avian theropods, which can be further investigated with additional discoveries of embryo fossils.

@article{doi101016jisci2021103516,
    author = "Xing, Lida and Niu, Kecheng and Ma, Waisum and Zelenitsky, Darla K. and Yang, Tzu-Ruei and Brusatte, Stephen L.",
    title = "An exquisitely preserved in-ovo theropod dinosaur embryo sheds light on avian-like prehatching postures",
    year = "2021",
    journal = "iScience",
    abstract = "embryos are remarkably rare. Here we report an exceptionally preserved, articulated oviraptorid embryo inside an elongatoolithid egg, from the Late Cretaceous Hekou Formation of southern China. The head lies ventral to the body, with the feet on either side, and the back curled along the blunt pole of the egg, in a posture previously unrecognized in a non-avian dinosaur, but reminiscent of a late-stage modern bird embryo. Comparison to other late-stage oviraptorid embryos suggests that prehatch oviraptorids developed avian-like postures late in incubation, which in modern birds are related to coordinated embryonic movements associated with tucking - a behavior controlled by the central nervous system, critical for hatching success. We propose that such pre-hatching behavior, previously considered unique to birds, may have originated among non-avian theropods, which can be further investigated with additional discoveries of embryo fossils.",
    url = "https://doi.org/10.1016/j.isci.2021.103516",
    doi = "10.1016/j.isci.2021.103516",
    openalex = "W4200185644",
    references = "doi101038ncomms4788, doi1012060003009044011, doi101642auk152161, doi1033740140540102, lee2019a"
}

Well-sampled dinosaur communities from the Jurassic through the early Late Cretaceous show greater taxonomic diversity among larger (>50 kg) theropod taxa than communities of the Campano-Maastrichtian, particularly to those of eastern/central Asia and Laramidia. The large carnivore guilds in Asiamerican assemblages are monopolized by tyrannosaurids, with adult medium-sized (50–500 kg) predators rare or absent. In contrast, various clades of theropods are found to occupy these body sizes in earlier faunas, including early tyrannosauroids. Assemblages with “missing middle-sized” predators are not found to have correspondingly sparser diversity of potential prey species recorded in these same faunas. The “missing middle-sized” niches in the theropod guilds of Late Cretaceous Laramidia and Asia may have been assimilated by juvenile and subadults of tyrannosaurid species, functionally distinct from their adult ecomorphologies. It is speculated that if tyrannosaurids assimilated the niches previously occupied by mid-sized theropod predators, we would expect the evolution of distinct transitions in morphology and possibly the delay of the achievement of somatic maturity in species of this taxon.

@article{doi101139cjes20200174,
    author = "Holtz, Thomas R.",
    title = "Theropod guild structure and the tyrannosaurid niche assimilation hypothesis: implications for predatory dinosaur macroecology and ontogeny in later Late Cretaceous Asiamerica 1",
    year = "2021",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "Well-sampled dinosaur communities from the Jurassic through the early Late Cretaceous show greater taxonomic diversity among larger (>50 kg) theropod taxa than communities of the Campano-Maastrichtian, particularly to those of eastern/central Asia and Laramidia. The large carnivore guilds in Asiamerican assemblages are monopolized by tyrannosaurids, with adult medium-sized (50–500 kg) predators rare or absent. In contrast, various clades of theropods are found to occupy these body sizes in earlier faunas, including early tyrannosauroids. Assemblages with “missing middle-sized” predators are not found to have correspondingly sparser diversity of potential prey species recorded in these same faunas. The “missing middle-sized” niches in the theropod guilds of Late Cretaceous Laramidia and Asia may have been assimilated by juvenile and subadults of tyrannosaurid species, functionally distinct from their adult ecomorphologies. It is speculated that if tyrannosaurids assimilated the niches previously occupied by mid-sized theropod predators, we would expect the evolution of distinct transitions in morphology and possibly the delay of the achievement of somatic maturity in species of this taxon.",
    url = "https://doi.org/10.1139/cjes-2020-0174",
    doi = "10.1139/cjes-2020-0174",
    openalex = "W3168560974",
    references = "doi101016jcub201803042, doi101017pab201519, doi101017s0094837300011891, doi10103846266, doi101038nature02699, doi101038ncomms3827, doi101038s4155901908880, doi101038s41598019517095, doi101038srep20252, doi101073pnas1600140113, doi101093nsrnwu055, doi101098rspb20202258, doi101111brv12638, doi101111j1469185x201000137x, doi101111j15023931200900187x, doi101126sciadvaax6250, doi101126science1065522, doi101126science1161833, doi101126science28454232137, doi101139cjes20120185, doi101139cjes20170031, doi101139cjes20190019, doi101371journalpone0054329, doi101371journalpone0188426, doi1017161paleo180818764, doi1023071942327, doi1023072411924, doi1029920070860302, doi103897zookeys92847517, doi107717peerj9192, openalexw2183707334, openalexw2971401580"
}

Modern birds are typified by the presence of feathers, complex evolutionary innovations that were already widespread in the group of theropod dinosaurs (Maniraptoriformes) that include crown Aves. Squamous or scaly reptilian-like skin is, however, considered the plesiomorphic condition for theropods and dinosaurs more broadly. Here, we review the morphology and distribution of non-feathered integumentary structures in non-avialan theropods, covering squamous skin and naked skin as well as dermal ossifications. The integumentary record of non-averostran theropods is limited to tracks, which ubiquitously show a covering of tiny reticulate scales on the plantar surface of the pes. This is consistent also with younger averostran body fossils, which confirm an arthral arrangement of the digital pads. Among averostrans, squamous skin is confirmed in Ceratosauria (Carnotaurus), Allosauroidea (Allosaurus, Concavenator, Lourinhanosaurus), Compsognathidae (Juravenator), and Tyrannosauroidea (Santanaraptor, Albertosaurus, Daspletosaurus, Gorgosaurus, Tarbosaurus, Tyrannosaurus), whereas dermal ossifications consisting of sagittate and mosaic osteoderms are restricted to Ceratosaurus. Naked, non-scale bearing skin is found in the contentious tetanuran Sciurumimus, ornithomimosaurians (Ornithomimus) and possibly tyrannosauroids (Santanaraptor), and also on the patagia of scansoriopterygids (Ambopteryx, Yi). Scales are surprisingly conservative among non-avialan theropods compared to some dinosaurian groups (e.g. hadrosaurids); however, the limited preservation of tegument on most specimens hinders further interrogation. Scale patterns vary among and/or within body regions in Carnotaurus, Concavenator and Juravenator, and include polarised, snake-like ventral scales on the tail of the latter two genera. Unusual but more uniformly distributed patterning also occurs in Tyrannosaurus, whereas feature scales are present only in Albertosaurus and Carnotaurus. Few theropods currently show compelling evidence for the co-occurrence of scales and feathers (e.g. Juravenator, Sinornithosaurus), although reticulate scales were probably retained on the mani and pedes of many theropods with a heavy plumage. Feathers and filamentous structures appear to have replaced widespread scaly integuments in maniraptorans. Theropod skin, and that of dinosaurs more broadly, remains a virtually untapped area of study and the appropriation of commonly used techniques in other palaeontological fields to the study of skin holds great promise for future insights into the biology, taphonomy and relationships of these extinct animals.

@article{doi101111brv12829,
    author = "Hendrickx, Christophe and Bell, Phil R. and Pittman, Michael and Milner, Andrew R. and Cuesta, Elena and O’Connor, Jingmai K. and Loewen, Mark A. and Currie, Philip J. and Mateus, Octávio and Kaye, Thomas G. and Delcourt, Rafael",
    title = "Morphology and distribution of scales, dermal ossifications, and other non‐feather integumentary structures in non‐avialan theropod dinosaurs",
    year = "2022",
    journal = "Biological reviews/Biological reviews of the Cambridge Philosophical Society",
    abstract = "Modern birds are typified by the presence of feathers, complex evolutionary innovations that were already widespread in the group of theropod dinosaurs (Maniraptoriformes) that include crown Aves. Squamous or scaly reptilian-like skin is, however, considered the plesiomorphic condition for theropods and dinosaurs more broadly. Here, we review the morphology and distribution of non-feathered integumentary structures in non-avialan theropods, covering squamous skin and naked skin as well as dermal ossifications. The integumentary record of non-averostran theropods is limited to tracks, which ubiquitously show a covering of tiny reticulate scales on the plantar surface of the pes. This is consistent also with younger averostran body fossils, which confirm an arthral arrangement of the digital pads. Among averostrans, squamous skin is confirmed in Ceratosauria (Carnotaurus), Allosauroidea (Allosaurus, Concavenator, Lourinhanosaurus), Compsognathidae (Juravenator), and Tyrannosauroidea (Santanaraptor, Albertosaurus, Daspletosaurus, Gorgosaurus, Tarbosaurus, Tyrannosaurus), whereas dermal ossifications consisting of sagittate and mosaic osteoderms are restricted to Ceratosaurus. Naked, non-scale bearing skin is found in the contentious tetanuran Sciurumimus, ornithomimosaurians (Ornithomimus) and possibly tyrannosauroids (Santanaraptor), and also on the patagia of scansoriopterygids (Ambopteryx, Yi). Scales are surprisingly conservative among non-avialan theropods compared to some dinosaurian groups (e.g. hadrosaurids); however, the limited preservation of tegument on most specimens hinders further interrogation. Scale patterns vary among and/or within body regions in Carnotaurus, Concavenator and Juravenator, and include polarised, snake-like ventral scales on the tail of the latter two genera. Unusual but more uniformly distributed patterning also occurs in Tyrannosaurus, whereas feature scales are present only in Albertosaurus and Carnotaurus. Few theropods currently show compelling evidence for the co-occurrence of scales and feathers (e.g. Juravenator, Sinornithosaurus), although reticulate scales were probably retained on the mani and pedes of many theropods with a heavy plumage. Feathers and filamentous structures appear to have replaced widespread scaly integuments in maniraptorans. Theropod skin, and that of dinosaurs more broadly, remains a virtually untapped area of study and the appropriation of commonly used techniques in other palaeontological fields to the study of skin holds great promise for future insights into the biology, taphonomy and relationships of these extinct animals.",
    url = "https://doi.org/10.1111/brv.12829",
    doi = "10.1111/brv.12829",
    openalex = "W4206485050",
    references = "crossref1998encyclopedia, doi101002jmor10382, doi101016jcub201706071, doi101016jcub202006105, doi101016jgca201006017, doi101016s001678780180047x, doi101017jpa202014, doi10103831635, doi10103834356, doi10103835047056, doi101038ncomms14972, doi101038s41598018371862, doi101038srep44942, doi1010800272463420211897604, doi101080147720192013781067, doi101093biolinneanblaa105, doi101093zoolinneanzly009, doi101111brv12829, doi101111cla12160, doi101126science28454232137, doi1011270077774920100125, doi101146annurevearth060313054858, doi1012063521, doi101371journalpone0044012, doi101371journalpone0125819, doi1017161paleo180818764, doi1017161pc180818764, doi10230725058147, doi105962bhltitle5716, doi107717peerj4066, doi107717peerj7247, doi107717peerj7963, doi107717peerj9192, erickson2014on, openalexw1915591379, openalexw2619609965"
}

Titanosaurian sauropod dinosaurs were diverse and abundant throughout the Cretaceous, with a global distribution. However, few titanosaurian taxa are represented by multiple skeletons, let alone skulls. Diamantinasaurus matildae, from the lower Upper Cretaceous Winton Formation of Queensland, Australia, was heretofore represented by three specimens, including one that preserves a braincase and several other cranial elements. Herein, we describe a fourth specimen of Diamantinasaurus matildae that preserves a more complete skull-including numerous cranial elements not previously known for this taxon-as well as a partial postcranial skeleton. The skull of Diamantinasaurus matildae shows many similarities to that of the coeval Sarmientosaurus musacchioi from Argentina (e.g. quadratojugal with posterior tongue-like process; braincase with more than one ossified exit for cranial nerve V; compressed-cone-chisel-like teeth), providing further support for the inclusion of both taxa within the clade Diamantinasauria. The replacement teeth within the premaxilla of the new specimen are morphologically congruent with teeth previously attributed to Diamantinasaurus matildae, and Diamantinasauria more broadly, corroborating those referrals. Plesiomorphic characters of the new specimen include a sacrum comprising five vertebrae (also newly demonstrated in the holotype of Diamantinasaurus matildae), rather than the six or more that typify other titanosaurs. However, we demonstrate that there have been a number of independent acquisitions of a six-vertebrae sacrum among Somphospondyli and/or that there have been numerous reversals to a five-vertebrae sacrum, suggesting that sacral count is relatively plastic. Other newly identified plesiomorphic features include: the overall skull shape, which is more similar to brachiosaurids than 'derived' titanosaurs; anterior caudal centra that are amphicoelous, rather than procoelous; and a pedal phalangeal formula estimated as 2-2-3-2-0. These features are consistent with either an early-branching position within Titanosauria, or a position just outside the titanosaurian radiation, for Diamantinasauria, as indicated by alternative character weighting approaches applied in our phylogenetic analyses, and help to shed light on the early assembly of titanosaurian anatomy that has until now been obscured by a poor fossil record.

@article{doi101098rsos221618,
    author = "Poropat, Stephen F. and Mannion, Philip D. and Rigby, Samantha L. and Duncan, Ruairidh J. and Pentland, Adele H. and Bevitt, Joseph J. and Sloan, Trish and Elliott, David A.",
    title = "A nearly complete skull of the sauropod dinosaur Diamantinasaurus matildae from the Upper Cretaceous Winton Formation of Australia and implications for the early evolution of titanosaurs",
    year = "2023",
    journal = "Royal Society Open Science",
    abstract = "Titanosaurian sauropod dinosaurs were diverse and abundant throughout the Cretaceous, with a global distribution. However, few titanosaurian taxa are represented by multiple skeletons, let alone skulls. Diamantinasaurus matildae, from the lower Upper Cretaceous Winton Formation of Queensland, Australia, was heretofore represented by three specimens, including one that preserves a braincase and several other cranial elements. Herein, we describe a fourth specimen of Diamantinasaurus matildae that preserves a more complete skull-including numerous cranial elements not previously known for this taxon-as well as a partial postcranial skeleton. The skull of Diamantinasaurus matildae shows many similarities to that of the coeval Sarmientosaurus musacchioi from Argentina (e.g. quadratojugal with posterior tongue-like process; braincase with more than one ossified exit for cranial nerve V; compressed-cone-chisel-like teeth), providing further support for the inclusion of both taxa within the clade Diamantinasauria. The replacement teeth within the premaxilla of the new specimen are morphologically congruent with teeth previously attributed to Diamantinasaurus matildae, and Diamantinasauria more broadly, corroborating those referrals. Plesiomorphic characters of the new specimen include a sacrum comprising five vertebrae (also newly demonstrated in the holotype of Diamantinasaurus matildae), rather than the six or more that typify other titanosaurs. However, we demonstrate that there have been a number of independent acquisitions of a six-vertebrae sacrum among Somphospondyli and/or that there have been numerous reversals to a five-vertebrae sacrum, suggesting that sacral count is relatively plastic. Other newly identified plesiomorphic features include: the overall skull shape, which is more similar to brachiosaurids than 'derived' titanosaurs; anterior caudal centra that are amphicoelous, rather than procoelous; and a pedal phalangeal formula estimated as 2-2-3-2-0. These features are consistent with either an early-branching position within Titanosauria, or a position just outside the titanosaurian radiation, for Diamantinasauria, as indicated by alternative character weighting approaches applied in our phylogenetic analyses, and help to shed light on the early assembly of titanosaurian anatomy that has until now been obscured by a poor fossil record.",
    url = "https://doi.org/10.1098/rsos.221618",
    doi = "10.1098/rsos.221618",
    openalex = "W4365147243",
    references = "doi101038srep19165, doi101093zoolinneanzlx103, doi101093zoolinneanzly068, doi101111cla12524, doi1011646zootaxa370131, doi1011646zootaxa384811, doi101371journalpone0151661"
}

@article{wang2023a,
    author = "Wang, Xuri and Cau, Andrea and Wang, Zhengdong and Yu, Kaifeng and Wu, Wenhao and Wang, Yang and Liu, Yichuan",
    title = "A new theropod dinosaur from the Lower Cretaceous Longjiang Formation of Inner Mongolia (China)",
    year = "2023",
    journal = "Cretaceous Research",
    url = "https://doi.org/10.1016/j.cretres.2023.105605",
    doi = "10.1016/j.cretres.2023.105605",
    openalex = "W4379468821",
    pages = "105605",
    volume = "151",
    references = "doi10103831635, doi101038nature00930, doi101038nature01342, doi101038nature08322, doi101038nature10288, doi101111j10960031200800217x, doi10230730135049, doi105281zenodo16171435, doi105860choice434677, openalexw3215057009"
}

@article{buntin2025a,
    author = "Buntin, Rogers C.C. and Moklestad, Tom and Matthews, Neffra A. and Breithaupt, Brent and Murphey, Paul C. and Kapinos, Ian and Noffke, Nora",
    title = "A new theropod dinosaur lek in the Cretaceous Dakota Sandstone (Dinosaur Ridge, Colorado, USA)",
    year = "2025",
    journal = "Cretaceous Research",
    url = "https://doi.org/10.1016/j.cretres.2025.106176",
    doi = "10.1016/j.cretres.2025.106176",
    pages = "106176",
    volume = "176"
}