Compsognathoids

It is a remarkable fact that the seven skeletons of Triassic dinosaurs now known from the eastern part of this continent are all carnivorous forms and of moderate size.There is abundant evidence from footprints that large herbivorous dinosaurs lived here at the same time, but no bones nor teeth have yet been found.In the western part of this country a few fragments of a large dinosaur have been discovered in strata of supposed Triassic age, but with this possible exception osseous remains of these forms appear to be wanting in this horizon.Fragmentary remains, also, of dinosaurs have been found in the Triassic deposits of Pennsylvania and North Carolina, but they throw little light on the animals they represent.Footprints, apparently made by dinosaurs, occur in New Jersey in the same horizon as those of the Connecticut Valley.Impressions of similar form have been discovered also in the Triassic sandstones of New Mexico.A few bones of a large dinosaurian were found by Prof. J.S. Newberry, in strata apparently of this age, in southeastern Utah.These remains were named by Professor Cope, Dystropheus viemale, in 1877, but their near affinities have not been determined.A single vertebra, apparently belonging in this group, had been previously found at Bathurst Island, Arctic America, and described by Prof. Leith Adams, in 1875, under the generic name Arctosaurus.The European Triassic dinosaurs, with which the American forms may be compared, are mainly represented by the two genera Thecodontosaurus Riley and Stutchbury, from the upper Trias, or Rheetic, near Bristol, in England, and Plateosaurus (Zanclodon) von Meyer, from nearly the same horizon in Germany.The writer has investigated with care the type specimens and nearly all the other known remains of these genera found at these localities.Remains of dinosaurs have been found in Triassic strata, also, in India, in South Africa, and in Australia, but the specimens discovered were mostly fragmentary, and apparently indicate no new types.BeAG Re tele: JURASSIC DINOSAURS.During the Jurassic period the dinosaurs of North America attained remarkable development, and, asa group, appear to have reached their culmination.The Theropoda, or carnivorous forms, which were so abundant, though of moderate size, in the Triassic, were represented in the Jurassic by many and various forms; some were very minute, but others were of gigantic size and dominated all living creatures during this age.

@book{doi105962bhltitle60562,
    author = "Marsh, O. C.",
    title = "The dinosaurs of North America",
    year = "1896",
    booktitle = "Govt. Print. Off. eBooks",
    abstract = "It is a remarkable fact that the seven skeletons of Triassic dinosaurs now known from the eastern part of this continent are all carnivorous forms and of moderate size.There is abundant evidence from footprints that large herbivorous dinosaurs lived here at the same time, but no bones nor teeth have yet been found.In the western part of this country a few fragments of a large dinosaur have been discovered in strata of supposed Triassic age, but with this possible exception osseous remains of these forms appear to be wanting in this horizon.Fragmentary remains, also, of dinosaurs have been found in the Triassic deposits of Pennsylvania and North Carolina, but they throw little light on the animals they represent.Footprints, apparently made by dinosaurs, occur in New Jersey in the same horizon as those of the Connecticut Valley.Impressions of similar form have been discovered also in the Triassic sandstones of New Mexico.A few bones of a large dinosaurian were found by Prof. J.S. Newberry, in strata apparently of this age, in southeastern Utah.These remains were named by Professor Cope, Dystropheus viemale, in 1877, but their near affinities have not been determined.A single vertebra, apparently belonging in this group, had been previously found at Bathurst Island, Arctic America, and described by Prof. Leith Adams, in 1875, under the generic name Arctosaurus.The European Triassic dinosaurs, with which the American forms may be compared, are mainly represented by the two genera Thecodontosaurus Riley and Stutchbury, from the upper Trias, or Rheetic, near Bristol, in England, and Plateosaurus (Zanclodon) von Meyer, from nearly the same horizon in Germany.The writer has investigated with care the type specimens and nearly all the other known remains of these genera found at these localities.Remains of dinosaurs have been found in Triassic strata, also, in India, in South Africa, and in Australia, but the specimens discovered were mostly fragmentary, and apparently indicate no new types.BeAG Re tele: JURASSIC DINOSAURS.During the Jurassic period the dinosaurs of North America attained remarkable development, and, asa group, appear to have reached their culmination.The Theropoda, or carnivorous forms, which were so abundant, though of moderate size, in the Triassic, were represented in the Jurassic by many and various forms; some were very minute, but others were of gigantic size and dominated all living creatures during this age.",
    url = "https://doi.org/10.5962/bhl.title.60562",
    doi = "10.5962/bhl.title.60562",
    openalex = "W649905387"
}

@article{openalexw1821824396,
    author = "Osborn, Henry Fairfield",
    title = "Ornitholestes hermanni, a new compsognathoid dinosaur from the Upper Jurassic. Bulletin of the AMNH; v. 19, article 12.",
    year = "1903",
    journal = "Biodiversity Heritage Library (Smithsonian Institution)",
    url = "https://openalex.org/W1821824396",
    openalex = "W1821824396"
}

@techreport{osborn1903ornitholestes1,
    author = "Osborn, H. F",
    title = "Ornitholestes hermanni, a new compsognathoid dinosaur from the Upper Jurassic",
    year = "1903",
    howpublished = "Bulletin of the American Museum of Natural History, v. 19, p. 459-464",
    note = "talkorigins\_source = {true}; raw\_reference = {Osborn, H. F., 1903, Ornitholestes hermanni, a new compsognathoid dinosaur from the Upper Jurassic: Bulletin of the American Museum of Natural History, v. 19, p. 459-464.}"
}

@article{schuchert1934the,
    author = "Schuchert, C.",
    title = "The upper Jurassic age of the Tendaguru dinosaur beds",
    year = "1934",
    journal = "American Journal of Science",
    url = "https://doi.org/10.2475/ajs.s5-27.162.463",
    doi = "10.2475/ajs.s5-27.162.463",
    number = "162",
    openalex = "W2313906088",
    pages = "463-466",
    volume = "s5-27"
}

The Upper Jurassic Morrison Formation has yielded one of the richest dinosaur faunas of the world. Morrison sediments are distributed over more than a million square kilometers in the western United States and represent a mosaic of riverine, lacustrine and floodplain environments developed on a vast alluvial plain nourished by debris from the ancestral Rocky Mountains. Plant productivity must have been reasonably high to support abundant large-bodied herbivores, but the absence of coals, scarcity of small aquatic vertebrates, the abundance of oxidized sediments, and presence of calcretes lead us to believe that water was periodically in short supply. A strongly seasonal climate may have necessitated annual large-scale movements of large herbivores, accounting in part for their remarkably broad and uniform geographic distribution. Dinosaur diversity is lower in the Morrison than in the Late Cretaceous, and taphonomic alteration is higher. Massed accumulations of thousands of bones are characteristic of the Morrison. Morrison dinosaurs were not confined to specific depositional environments but were distributed across the complete spectrum of available habitats, from lakes to dry floodplains; this type of distribution is similar to that of large terrestrial mammals such as elephants and rhinos and is different from that of hippos and crocodiles. Common Morrison taxa were Camarasaurus, Apatosaurus, Diplodocus, Allosaurus and Stegosaurus; these genera probably constituted a true dinosaur community. Stegosaurus may have been partially segregated from the other genera, and Camptosaurus more strongly so. Camarasaurus and Diplodocus were gregarious, with juveniles and subadults of the former particularly common; Apatosaurus was less abundant and more solitary in its habits. Juveniles and subadults are known for a number of dinosaurs.

@article{doi101017s009483730000676x,
    author = "Dodson, Peter and Behrensmeyer, Anna K. and Bakker, Robert T. and McIntosh, John S.",
    title = "Taphonomy and Paleoecology of the Dinosaur Beds of the Jurassic Morrison Formation",
    year = "1980",
    journal = "Paleobiology",
    abstract = "The Upper Jurassic Morrison Formation has yielded one of the richest dinosaur faunas of the world. Morrison sediments are distributed over more than a million square kilometers in the western United States and represent a mosaic of riverine, lacustrine and floodplain environments developed on a vast alluvial plain nourished by debris from the ancestral Rocky Mountains. Plant productivity must have been reasonably high to support abundant large-bodied herbivores, but the absence of coals, scarcity of small aquatic vertebrates, the abundance of oxidized sediments, and presence of calcretes lead us to believe that water was periodically in short supply. A strongly seasonal climate may have necessitated annual large-scale movements of large herbivores, accounting in part for their remarkably broad and uniform geographic distribution. Dinosaur diversity is lower in the Morrison than in the Late Cretaceous, and taphonomic alteration is higher. Massed accumulations of thousands of bones are characteristic of the Morrison. Morrison dinosaurs were not confined to specific depositional environments but were distributed across the complete spectrum of available habitats, from lakes to dry floodplains; this type of distribution is similar to that of large terrestrial mammals such as elephants and rhinos and is different from that of hippos and crocodiles. Common Morrison taxa were Camarasaurus, Apatosaurus, Diplodocus, Allosaurus and Stegosaurus; these genera probably constituted a true dinosaur community. Stegosaurus may have been partially segregated from the other genera, and Camptosaurus more strongly so. Camarasaurus and Diplodocus were gregarious, with juveniles and subadults of the former particularly common; Apatosaurus was less abundant and more solitary in its habits. Juveniles and subadults are known for a number of dinosaurs.",
    url = "https://doi.org/10.1017/s009483730000676x",
    doi = "10.1017/s009483730000676x",
    openalex = "W2198607068",
    references = "crossref1976allosaurus, doi101017s0094837300005820, doi101111j109636421961tb00220x, doi101111j146979981975tb01405x, doi10113000167606196879429sobina20co2, doi1023071935678, doi1023072424244, doi102475ajss31484514, doi102475ajss319111253, doi105962bhlpart22969, doi105962p234849, madsen1976a"
}

ABSTRACT The sandstones and coquinas of the upper 20 m of the Sundance Formation are interpreted as a tidal inlet, back‐barrier shoal and sandy tidal‐flat sequence deposited at the close of marine Jurassic sedimentation in north‐central Wyoming. The barrier strandline maintained a generally E‐W trend as it prograded to the north. The lateral migration of inter‐barrier tidal inlets along the regressive shoreline of the late Sundance sea caused the coquinas and sandstones of the uppermost Sundance Formation to be deposited as tabular, laterally‐extensive units. Tidal bundles, sigmoidal reactivation surfaces, herringbone cross‐lamination and abundant mud drapes within the sandstones are evidence of considerable tidal influence during the deposition of the uppermost Sundance Formation. Earlier models, which attach an offshore environment of deposition to the sequence, do not explain the tabular geometries of the sandstone and coquina units and their conformable stratigraphic relationship with the overlying non‐marine sediments of the Morrison Formation.

@article{doi101111j136530911988tb01248x,
    author = "Uhlir, D.M. and Akers, A. and Vondra, Carl F.",
    title = "Tidal inlet sequence, Sundance Formation (Upper Jurassic), north‐central Wyoming",
    year = "1988",
    journal = "Sedimentology",
    abstract = "ABSTRACT The sandstones and coquinas of the upper 20 m of the Sundance Formation are interpreted as a tidal inlet, back‐barrier shoal and sandy tidal‐flat sequence deposited at the close of marine Jurassic sedimentation in north‐central Wyoming. The barrier strandline maintained a generally E‐W trend as it prograded to the north. The lateral migration of inter‐barrier tidal inlets along the regressive shoreline of the late Sundance sea caused the coquinas and sandstones of the uppermost Sundance Formation to be deposited as tabular, laterally‐extensive units. Tidal bundles, sigmoidal reactivation surfaces, herringbone cross‐lamination and abundant mud drapes within the sandstones are evidence of considerable tidal influence during the deposition of the uppermost Sundance Formation. Earlier models, which attach an offshore environment of deposition to the sequence, do not explain the tabular geometries of the sandstone and coquina units and their conformable stratigraphic relationship with the overlying non‐marine sediments of the Morrison Formation.",
    url = "https://doi.org/10.1111/j.1365-3091.1988.tb01248.x",
    doi = "10.1111/j.1365-3091.1988.tb01248.x",
    openalex = "W2036213223",
    references = "doi101016b978012197502950006x, doi101111j136530911974tb01788x, doi101111j136530911981tb01674x, doi101111j136530911984tb00723x, doi101111j136530911985tb00491x, doi10113000167606198697381stbaot20co2, doi1011300091761319808543ncrihs20co2, doi101306212f78b52b2411d78648000102c1865d, doi101306212f85032b2411d78648000102c1865d, doi105724gcs84030347, kvaleNonepaleoenvironments"
}

The record of life on land has been a principal concern of historical biology not only because of our fascination with our own past (and with giants, dragons, and other ancient monsters) but because of special opportunities and challenges for development of methods, principles, and concepts of explanation. The Beginning of the Age of Dinosaurs treats an intriguing phase of that history, one that included the first appearance of dinosaurs, and mammals, the extinction or near extinction of many clades of vertebrates, and extensive changes in plant associations. Further, the patterns of change (and of stasis) raise general questions about macroecologic and macroevolutionary processes and factors and even about the roles of chance and determination in biological history. Although the book was published initially in 1986 (and was based on a 1984 symposium sponsored by the Society of Vertebrate Paleontologists), its content remains current and its release in paperback form (for $34.50 rather than $75.00 for the hardcover version) justifies a review even at this late date. The Introduction and the Summary and Prospectus, written by the editor, Kevin Padian, demonstrate the significance of the interval from mid-Triassic to early Jurassic-particularly for vertebrates on land. Advanced mammal-like reptiles (therapsids) dominate lower Triassic assemblages in abundance, taxonomic diversity, and ecological variety; non-therapsids (mostly archosaurs) are rare elements and apparently of little ecological importance. In upper Triassic and lower Jurassic assemblages the situation is reversed, therapsids rare with limited diversity and variety but archosaurs abundant, diverse and varied. The archosaur expansion starts in middle of the succession; pterodactyls, crocodylomorphs, and dinosaurs appear (as archosaur subclades) in approximate coincidence with a marked decline in therapsids. Mammals (at least 3 subclades) occur along with two other subclades of very mammal-like therapsids very close to the top. In the upper Triassic two relatively sharp breaks in faunal composition appear, one relatively low, in the top of the Carnian and base of the Norian stages (around 225 Ma), and one higher, at the top of the Norian (around 215 Ma). These breaks, if real and not a consequence of miscorrelations or gaps in sampling, suggest high rates of taxonomic extinction and origination and have been interpreted as intervals of catastrophic extinction. These changes coincide more or less with some in the flora (except that the latter seem continuous rather than stepped) and thus with overall changes in terrestrial ecosystems. Radically different explanations have been offered for these patterns, at one extreme a deterministic argument from the competitive superiority of dinosaurs to the other, an opportunistic one based on chance differences in survival through episodes of mass extinction. This book can be viewed (and reviewed) as an extended example of analysis and interpretation in historical biology. The concerns of the discipline are twofold, chronicle and narrative (the concepts those of O'Hara, 1988). Chronicle comprises when, what, and where; narrative, how. A chronicle extends of course beyond description and chronologic ordering of fossils to paleobiogeographic, paleoecologic, and phylogenetic reconstructions. The latter derive from patterns in form and occurrence of fossils as analyzed in terms of taphonomic, constructional, functional, and phylogenetic processes and factors (viz Seilacher, 1970) and of stratigraphic and geographic distribution. Each reconstruction represents a particular state, and stratigraphic analysis arranges these reconstructions into a chronicle. Narrative, in contrast, involves explanation of the patterns (temporal, geographic, ecologic and phyletic) in the chronicle by a sequence of biological and physical circumstances and by evolutionary processes and factors (genetic, phylogenetic, and ecological). Of the 26 papers in this volume, 24 focus primarily on the chronicle and are dominated by consideration of what-when, i.e., the stratigraphic distribution of various groups of fossils, and of what-how, i.e., the phylogenetic and functional analyses. Among those in the what-when group are papers by Colbert on historical aspects of upper Triassic-lower Jurassic stratigraphy, by Ash on fossil plants, by Olsen and Baird on the ichnogenus Atreipus, by Chatterjee and by Parrish and Carpenter on vertebrates of the Dockum Group (Texas and New Mexico), and by Long and Padian on biostratigraphy of the Chinle Formation (Arizona). Also best included here are the studies by McCune and Schaeffer on Triassic and Jurassic fishes, Gaffney on turtles, Clemens on mammals, Olson and Padian on crocodylomorph ichnogenera, Sun and Cui on saurishians from the lower Lufeng (China), Clark and Fastovsky on the vertebrates of the Glen Canyon Group (Arizona), Haubold on archosaur trackways, Sigogneau-Russell, Frank, and Hemmerle on a new family of Triassic

@article{doi1023073514751,
    author = "Beerbower, Richard and Padian, Kevin",
    title = "The Beginning of the Age of Dinosaurs",
    year = "1989",
    journal = "Palaios",
    abstract = "The record of life on land has been a principal concern of historical biology not only because of our fascination with our own past (and with giants, dragons, and other ancient monsters) but because of special opportunities and challenges for development of methods, principles, and concepts of explanation. The Beginning of the Age of Dinosaurs treats an intriguing phase of that history, one that included the first appearance of dinosaurs, and mammals, the extinction or near extinction of many clades of vertebrates, and extensive changes in plant associations. Further, the patterns of change (and of stasis) raise general questions about macroecologic and macroevolutionary processes and factors and even about the roles of chance and determination in biological history. Although the book was published initially in 1986 (and was based on a 1984 symposium sponsored by the Society of Vertebrate Paleontologists), its content remains current and its release in paperback form (for $34.50 rather than $75.00 for the hardcover version) justifies a review even at this late date. The Introduction and the Summary and Prospectus, written by the editor, Kevin Padian, demonstrate the significance of the interval from mid-Triassic to early Jurassic-particularly for vertebrates on land. Advanced mammal-like reptiles (therapsids) dominate lower Triassic assemblages in abundance, taxonomic diversity, and ecological variety; non-therapsids (mostly archosaurs) are rare elements and apparently of little ecological importance. In upper Triassic and lower Jurassic assemblages the situation is reversed, therapsids rare with limited diversity and variety but archosaurs abundant, diverse and varied. The archosaur expansion starts in middle of the succession; pterodactyls, crocodylomorphs, and dinosaurs appear (as archosaur subclades) in approximate coincidence with a marked decline in therapsids. Mammals (at least 3 subclades) occur along with two other subclades of very mammal-like therapsids very close to the top. In the upper Triassic two relatively sharp breaks in faunal composition appear, one relatively low, in the top of the Carnian and base of the Norian stages (around 225 Ma), and one higher, at the top of the Norian (around 215 Ma). These breaks, if real and not a consequence of miscorrelations or gaps in sampling, suggest high rates of taxonomic extinction and origination and have been interpreted as intervals of catastrophic extinction. These changes coincide more or less with some in the flora (except that the latter seem continuous rather than stepped) and thus with overall changes in terrestrial ecosystems. Radically different explanations have been offered for these patterns, at one extreme a deterministic argument from the competitive superiority of dinosaurs to the other, an opportunistic one based on chance differences in survival through episodes of mass extinction. This book can be viewed (and reviewed) as an extended example of analysis and interpretation in historical biology. The concerns of the discipline are twofold, chronicle and narrative (the concepts those of O'Hara, 1988). Chronicle comprises when, what, and where; narrative, how. A chronicle extends of course beyond description and chronologic ordering of fossils to paleobiogeographic, paleoecologic, and phylogenetic reconstructions. The latter derive from patterns in form and occurrence of fossils as analyzed in terms of taphonomic, constructional, functional, and phylogenetic processes and factors (viz Seilacher, 1970) and of stratigraphic and geographic distribution. Each reconstruction represents a particular state, and stratigraphic analysis arranges these reconstructions into a chronicle. Narrative, in contrast, involves explanation of the patterns (temporal, geographic, ecologic and phyletic) in the chronicle by a sequence of biological and physical circumstances and by evolutionary processes and factors (genetic, phylogenetic, and ecological). Of the 26 papers in this volume, 24 focus primarily on the chronicle and are dominated by consideration of what-when, i.e., the stratigraphic distribution of various groups of fossils, and of what-how, i.e., the phylogenetic and functional analyses. Among those in the what-when group are papers by Colbert on historical aspects of upper Triassic-lower Jurassic stratigraphy, by Ash on fossil plants, by Olsen and Baird on the ichnogenus Atreipus, by Chatterjee and by Parrish and Carpenter on vertebrates of the Dockum Group (Texas and New Mexico), and by Long and Padian on biostratigraphy of the Chinle Formation (Arizona). Also best included here are the studies by McCune and Schaeffer on Triassic and Jurassic fishes, Gaffney on turtles, Clemens on mammals, Olson and Padian on crocodylomorph ichnogenera, Sun and Cui on saurishians from the lower Lufeng (China), Clark and Fastovsky on the vertebrates of the Glen Canyon Group (Arizona), Haubold on archosaur trackways, Sigogneau-Russell, Frank, and Hemmerle on a new family of Triassic",
    url = "https://doi.org/10.2307/3514751",
    doi = "10.2307/3514751",
    openalex = "W2320472492",
    references = "doi101017cbo9780511608551, doi1023072807146, doi1023072992272"
}

The Upper Jurassic egg described here is the first known egg from the 100-million-year gap in the fossil record between Lower Jurassic (South Africa) and upper Lower Cretaceous (Utah). The discovery of the egg, which was found mixed in with thousands of dinosaur bones rather than in a nest, the pathological multilayering of the eggshell as found in modern and fossil reptilians, and the pliable condition of the eggshell at the time of burial indicate an oviducal retention of the egg at the time of burial.

@article{hirsch1989upper,
    author = "Hirsch, Karl F. and Stadtman, Kenneth L. and Miller, Wade E. and Madsen, James H.",
    title = "Upper Jurassic Dinosaur Egg from Utah",
    year = "1989",
    journal = "Science",
    abstract = "The Upper Jurassic egg described here is the first known egg from the 100-million-year gap in the fossil record between Lower Jurassic (South Africa) and upper Lower Cretaceous (Utah). The discovery of the egg, which was found mixed in with thousands of dinosaur bones rather than in a nest, the pathological multilayering of the eggshell as found in modern and fossil reptilians, and the pliable condition of the eggshell at the time of burial indicate an oviducal retention of the egg at the time of burial.",
    url = "https://doi.org/10.1126/science.243.4899.1711",
    doi = "10.1126/science.243.4899.1711",
    number = "4899",
    pages = "1711-1713",
    volume = "243"
}

In 1987, a Sino-Canadian expedition known as the Dinosaur Project (China – Canada – Alberta – Ex Terra) discovered a large theropod skeleton in the Upper Jurassic Shishugou Formation of the Junggar Basin in northwestern China. The well-preserved skeleton lacks much of the tail and most of the arms, but is otherwise nearly complete. The new genus and species, Sinraptor dongi, represents a poorly understood stage of theropod evolution, even though a related form, Megalosaurus, was the first dinosaur described and named (by W. Buckland in 1824). Sinraptor has a large pneumatopore in the jugal, a pronounced postorbital rugosity, a relatively long intertemporal bar in which the postorbital appears very short in lateral aspect, and a pneumatic palatine. It is more advanced than Piatnitzkysaurus from Argentina, less derived than Allosaurus, and shows its strongest similarities to Yangchuanosaurus. The preorbital skull length of Sinraptor is relatively longer than in Yangchuanosaurus, but the skull is relatively lower. A specimen from Sichuan recently described as "Yangchuanosaurus" hepingensis represents a second species of Sinraptor. Sinraptor and Yangchuanosaurus are united in a new family of theropods, the Sinraptoridae.

@article{doi101139e93179,
    author = "Currie, Philip J. and Zhao, Xi-Jin",
    title = "A new carnosaur (Dinosauria, Theropoda) from the Jurassic of Xinjiang, People's Republic of China",
    year = "1993",
    journal = "Canadian Journal of Earth Sciences",
    abstract = {In 1987, a Sino-Canadian expedition known as the Dinosaur Project (China – Canada – Alberta – Ex Terra) discovered a large theropod skeleton in the Upper Jurassic Shishugou Formation of the Junggar Basin in northwestern China. The well-preserved skeleton lacks much of the tail and most of the arms, but is otherwise nearly complete. The new genus and species, Sinraptor dongi, represents a poorly understood stage of theropod evolution, even though a related form, Megalosaurus, was the first dinosaur described and named (by W. Buckland in 1824). Sinraptor has a large pneumatopore in the jugal, a pronounced postorbital rugosity, a relatively long intertemporal bar in which the postorbital appears very short in lateral aspect, and a pneumatic palatine. It is more advanced than Piatnitzkysaurus from Argentina, less derived than Allosaurus, and shows its strongest similarities to Yangchuanosaurus. The preorbital skull length of Sinraptor is relatively longer than in Yangchuanosaurus, but the skull is relatively lower. A specimen from Sichuan recently described as "Yangchuanosaurus" hepingensis represents a second species of Sinraptor. Sinraptor and Yangchuanosaurus are united in a new family of theropods, the Sinraptoridae.},
    url = "https://doi.org/10.1139/e93-179",
    doi = "10.1139/e93-179",
    openalex = "W2126252810"
}

@article{foster1995tridactyl,
    author = "Foster, John R. and Lockley, Martin G.",
    title = "Tridactyl dinosaur footprints from the Morrison Formation (Upper Jurassic) of northeast Wyoming",
    year = "1995",
    journal = "Ichnos",
    url = "https://doi.org/10.1080/10420949509380112",
    doi = "10.1080/10420949509380112",
    number = "1",
    openalex = "W2035328845",
    pages = "35-41",
    volume = "4",
    references = "doi1010079789400904095, doi101038261129a0, doi101086410790, doi1023073514816, doi105860choice260307, doi105860choice332752, doi105962bhltitle70405, doi107312lock90868, openalexw603337959"
}

@article{meyer1998the,
    author = "Meyer, Christian A. and Hunt, Adrian P.",
    title = "The first stegosaurian dinosaur (Ornithischia: Thyreophora) from the Upper Jurassic of Switzerland",
    year = "1998",
    journal = "Neues Jahrbuch für Geologie und Paläontologie - Monatshefte",
    url = "https://doi.org/10.1127/njgpm/1998/1998/141",
    doi = "10.1127/njgpm/1998/1998/141",
    number = "3",
    openalex = "W2995070984",
    pages = "141-145",
    volume = "1998"
}

Tendaguru is one of the most important dinosaur localities in Africa. The Tendaguru Beds have produced a diverse Late Jurassic (Kimmeridgian to Tithonian) dinosaur assemblage, including sauropods (Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia), theropods (e.g., Elaphrosaurus, Ceratosaurus, Allosaurus), and ornithischians (Kentrosaurus, Dryosaurus). Contrary to the well studied skeletal anatomy of the Tendaguru dinosaurs, the available taphonomic information is rather limited, and a generally accepted taphonomic model has not yet been established. Assessment of unpublished excavation sketches by the German Tendaguru expedition (1909–1913) document bone assemblages of sauropod and ornithischian dinosaurs from the Middle Saurian Bed, Upper Saurian Bed, and the Transitional Sands above the Trigonia smeei Bed, and shed some light on the taphonomy of the Tendaguru dinosaurs. Stages of disarticulation range from incomplete skeletons to solitary bones, and strongly argue for carcass decay and post-mortem transport prior to burial. The sauropod bone accumulations are dominated by adult individuals, and juveniles are rare or missing. The occurrence of bones in different superimposed dinosaur-bearing horizons indicates that skeletal remains were accumulated over a long time span during the Late Jurassic, and the majority of the bone accumulations are probably attritional. These accumulations are likely to have resulted from long-term bone imput due to normal mortality events caused by starvation, seasonal drought, disease, old age and weakness. The depositional environment of the Middle and Upper Saurian Bed was mainly limnic to brackish in origin, while the palaeoenvironment of the Transitional Sands was marginal marine. Tendaguru zählt zu den bedeutendsten Dinosaurier-Lagerstätten Afrikas. Aus den Tendaguru-Schichten sind zahlreiche Skelettreste von Sauropoden (Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia), Theropoden (z.B. Elaphrosaurus, Ceratosaurus, Allosaurus) und Ornithischiern (Kentrosaurus, Dryosaurus) geborgen worden. Sie stammen aus der späten Jura-Zeit (Kimmeridge — Tithon). Während der Skelettbau der Tendagurusaurier gut untersucht ist, wirft die Taphonomie des Sauriervorkommens von Tendaguru noch immer Fragen auf. Unklar ist bislang, wie die enormen Anreicherungen von Dinosaurierknochen in den Tendaguru-Schichten zustandekamen. Unveröffentlichte Grabungsskizzen der Deutschen Tendaguru Expedition (1909–1913) erweitern unsere Kenntnisse über die Taphonomie der Tendagurusaurier. In den ausgewerteten Grabungsskizzen sind Knochenansammlungen von Sauropoden und Ornithischiern aus dem Mittleren und Oberen Sauriermergel sowie aus den Übergangsschichten über der Trigonia smeei-Schicht dokumentiert. Die Lage und der Erhaltungszustand der Funde lassen auf erheblichen Zerfall der Kadaver und post-mortalen Transport von Skelettelementen vor der Einbettung schließen. Das Vorkommen von Saurierknochen in mehreren übereinanderliegenden Profilabschnitten der Tendaguru-Schichten zeigt, daß Skelettreste während der späten Jura-Zeit über einen längeren Zeitraum hinweg akkumuliert wurden. Die Ansammlungen von Skelettresten gehen wahrscheinlich auf „normale” Sterbe-Ereignisse zurück, wie z. B. Verhungern, Verdursten, Kankheit, Altersschwäche und jahreszeitliche Dürre. Als Ablagerungsraum der Mittleren und Oberen Saurierschicht kommt ein küstennaher limnischer, zeitweise wohl auch brackischer Küstenstreifen in Betracht. Die knochenführenden Übergangsschichten unter- und oberhalb der Saurierschichten sind randlich marine Ablagerungen. doi:10.1002/mmng.1999.4860020102

@article{doi101002mmng19994860020102,
    author = "Heinrich, Wolf‐Dieter",
    title = "The taphonomy of dinosaurs from the Upper Jurassic of Tendaguru (Tanzania) based on field sketches of the German tendaguru expedition (1909-1913)",
    year = "1999",
    journal = "Fossil Record",
    abstract = "Tendaguru is one of the most important dinosaur localities in Africa. The Tendaguru Beds have produced a diverse Late Jurassic (Kimmeridgian to Tithonian) dinosaur assemblage, including sauropods (Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia), theropods (e.g., Elaphrosaurus, Ceratosaurus, Allosaurus), and ornithischians (Kentrosaurus, Dryosaurus). Contrary to the well studied skeletal anatomy of the Tendaguru dinosaurs, the available taphonomic information is rather limited, and a generally accepted taphonomic model has not yet been established. Assessment of unpublished excavation sketches by the German Tendaguru expedition (1909–1913) document bone assemblages of sauropod and ornithischian dinosaurs from the Middle Saurian Bed, Upper Saurian Bed, and the Transitional Sands above the Trigonia smeei Bed, and shed some light on the taphonomy of the Tendaguru dinosaurs. Stages of disarticulation range from incomplete skeletons to solitary bones, and strongly argue for carcass decay and post-mortem transport prior to burial. The sauropod bone accumulations are dominated by adult individuals, and juveniles are rare or missing. The occurrence of bones in different superimposed dinosaur-bearing horizons indicates that skeletal remains were accumulated over a long time span during the Late Jurassic, and the majority of the bone accumulations are probably attritional. These accumulations are likely to have resulted from long-term bone imput due to normal mortality events caused by starvation, seasonal drought, disease, old age and weakness. The depositional environment of the Middle and Upper Saurian Bed was mainly limnic to brackish in origin, while the palaeoenvironment of the Transitional Sands was marginal marine. Tendaguru zählt zu den bedeutendsten Dinosaurier-Lagerstätten Afrikas. Aus den Tendaguru-Schichten sind zahlreiche Skelettreste von Sauropoden (Brachiosaurus, Barosaurus, Dicraeosaurus, Janenschia), Theropoden (z.B. Elaphrosaurus, Ceratosaurus, Allosaurus) und Ornithischiern (Kentrosaurus, Dryosaurus) geborgen worden. Sie stammen aus der späten Jura-Zeit (Kimmeridge — Tithon). Während der Skelettbau der Tendagurusaurier gut untersucht ist, wirft die Taphonomie des Sauriervorkommens von Tendaguru noch immer Fragen auf. Unklar ist bislang, wie die enormen Anreicherungen von Dinosaurierknochen in den Tendaguru-Schichten zustandekamen. Unveröffentlichte Grabungsskizzen der Deutschen Tendaguru Expedition (1909–1913) erweitern unsere Kenntnisse über die Taphonomie der Tendagurusaurier. In den ausgewerteten Grabungsskizzen sind Knochenansammlungen von Sauropoden und Ornithischiern aus dem Mittleren und Oberen Sauriermergel sowie aus den Übergangsschichten über der Trigonia smeei-Schicht dokumentiert. Die Lage und der Erhaltungszustand der Funde lassen auf erheblichen Zerfall der Kadaver und post-mortalen Transport von Skelettelementen vor der Einbettung schließen. Das Vorkommen von Saurierknochen in mehreren übereinanderliegenden Profilabschnitten der Tendaguru-Schichten zeigt, daß Skelettreste während der späten Jura-Zeit über einen längeren Zeitraum hinweg akkumuliert wurden. Die Ansammlungen von Skelettresten gehen wahrscheinlich auf „normale” Sterbe-Ereignisse zurück, wie z. B. Verhungern, Verdursten, Kankheit, Altersschwäche und jahreszeitliche Dürre. Als Ablagerungsraum der Mittleren und Oberen Saurierschicht kommt ein küstennaher limnischer, zeitweise wohl auch brackischer Küstenstreifen in Betracht. Die knochenführenden Übergangsschichten unter- und oberhalb der Saurierschichten sind randlich marine Ablagerungen. doi:10.1002/mmng.1999.4860020102",
    url = "https://doi.org/10.1002/mmng.1999.4860020102",
    doi = "10.1002/mmng.1999.4860020102",
    openalex = "W2150973288",
    references = "doi101002mmng19994860020112, doi101002mmng19994860020115, doi101007bf02988144, doi101007bf02988803, doi101007bf03042228, doi101016003101829290100j, doi101016s0031018298000741, doi10108002724634199510011209, doi105860choice300309, openalexw3206774529, openalexw605949302, schuchert1934the"
}

Two previously unknown rare Middle Jurassic dinosaur megatracksites are reported from the Bighorn Basin of northern Wyoming in the Western Interior of the United States.These trace fossils occur in carbonate units once thought to be totally marine in origin, and constitute the two most extensive Middle Jurassic dinosaur tracksites currently known in North America.The youngest of these occurs primarily along a single horizon at or near the top of the ''basal member'' of the ''lower'' Sundance Formation, is mid-Bathonian in age, and dates to ϳ167 ma.This discovery necessitates a major change in the paleogeographic reconstructions for Wyoming for this period.The older tracksites occur at multiple horizons within a 1 m interval in the middle part of the Gypsum Spring Formation.This interval is uppermost Bajocian in age and dates to ϳ170 ma.Terrestrial tracks found, to date, have been all bipedal tridactyl dinosaur prints.At least some of these prints can be attributed to theropods.Possible swim tracks of bipedal dinosaurs are also present in the Gypsum Spring Formation.Digitigrade prints dominate the Sundance trackways, with both plantigrade and digitigrade prints being preserved in the Gypsum Spring trackways.The Sundance track-bearing surface locally covers 7.5 square kilometers in the vicinity of Shell, Wyoming.Other tracks occur apparently on the same horizon approximately 25 kilometers to the west, north of the town of Greybull.The Gypsum Spring megatracksite is locally preserved across the same 25 kilometer east-west expanse, with the Gypsum Spring megatracksite more extensive in a north-south direction with tracks occurring locally across a 100 kilometer extent.Conservative estimates for the trackway density based on regional mapping in the Sundance tracksite discovery area near Shell suggests that over 150,000 in situ tracks may be preserved per square kilometer in the Sundance Formation in this area.Comparable estimates have not been made for other areas.Similarities between the two megatracksites include their formation and preservation in upper intertidal to supratidal sediments deposited under at least seasonally arid conditions.Microbial mat growth on the ancient tidal flats apparently initiated the preservation of these prints.

@article{doi1016690883135120010160233mjbabd20co2,
    author = "Kvale, Erik P. and JOHNSON, A. D. and Mickelson, Debra L. and Keller, Kenneth W. and Furer, L.C. and Archer, Allen W.",
    title = "Middle Jurassic (Bajocian and Bathonian) Dinosaur Megatracksites, Bighorn Basin, Wyoming, U.S.A",
    year = "2001",
    journal = "Palaios",
    abstract = "Two previously unknown rare Middle Jurassic dinosaur megatracksites are reported from the Bighorn Basin of northern Wyoming in the Western Interior of the United States.These trace fossils occur in carbonate units once thought to be totally marine in origin, and constitute the two most extensive Middle Jurassic dinosaur tracksites currently known in North America.The youngest of these occurs primarily along a single horizon at or near the top of the ''basal member'' of the ''lower'' Sundance Formation, is mid-Bathonian in age, and dates to ϳ167 ma.This discovery necessitates a major change in the paleogeographic reconstructions for Wyoming for this period.The older tracksites occur at multiple horizons within a 1 m interval in the middle part of the Gypsum Spring Formation.This interval is uppermost Bajocian in age and dates to ϳ170 ma.Terrestrial tracks found, to date, have been all bipedal tridactyl dinosaur prints.At least some of these prints can be attributed to theropods.Possible swim tracks of bipedal dinosaurs are also present in the Gypsum Spring Formation.Digitigrade prints dominate the Sundance trackways, with both plantigrade and digitigrade prints being preserved in the Gypsum Spring trackways.The Sundance track-bearing surface locally covers 7.5 square kilometers in the vicinity of Shell, Wyoming.Other tracks occur apparently on the same horizon approximately 25 kilometers to the west, north of the town of Greybull.The Gypsum Spring megatracksite is locally preserved across the same 25 kilometer east-west expanse, with the Gypsum Spring megatracksite more extensive in a north-south direction with tracks occurring locally across a 100 kilometer extent.Conservative estimates for the trackway density based on regional mapping in the Sundance tracksite discovery area near Shell suggests that over 150,000 in situ tracks may be preserved per square kilometer in the Sundance Formation in this area.Comparable estimates have not been made for other areas.Similarities between the two megatracksites include their formation and preservation in upper intertidal to supratidal sediments deposited under at least seasonally arid conditions.Microbial mat growth on the ancient tidal flats apparently initiated the preservation of these prints.",
    url = "https://doi.org/10.1669/0883-1351(2001)016<0233:mjbabd>2.0.co;2",
    doi = "10.1669/0883-1351(2001)016<0233:mjbabd>2.0.co;2",
    openalex = "W2179114768",
    references = "doi101111j136530911988tb01248x"
}

Analysis of tetrapod footprints and skeletal material from more than 70 localities in eastern North America shows that large theropod dinosaurs appeared less than 10,000 years after the Triassic-Jurassic boundary and less than 30,000 years after the last Triassic taxa, synchronous with a terrestrial mass extinction. This extraordinary turnover is associated with an iridium anomaly (up to 285 parts per trillion, with an average maximum of 141 parts per trillion) and a fern spore spike, suggesting that a bolide impact was the cause. Eastern North American dinosaurian diversity reached a stable maximum less than 100,000 years after the boundary, marking the establishment of dinosaur-dominated communities that prevailed for the next 135 million years.

@article{doi101126science1065522,
    author = "Olsen, Paul E. and Kent, Dennis V. and Sues, Hans‐Dieter and Koeberl, Christian and Huber, Heinz and Montanari, Alessandro and Rainforth, Emma C. and Fowell, Sarah J. and Szajna, Michael J. and Hartline, B. W.",
    title = "Ascent of Dinosaurs Linked to an Iridium Anomaly at the Triassic-Jurassic Boundary",
    year = "2002",
    journal = "Science",
    abstract = "Analysis of tetrapod footprints and skeletal material from more than 70 localities in eastern North America shows that large theropod dinosaurs appeared less than 10,000 years after the Triassic-Jurassic boundary and less than 30,000 years after the last Triassic taxa, synchronous with a terrestrial mass extinction. This extraordinary turnover is associated with an iridium anomaly (up to 285 parts per trillion, with an average maximum of 141 parts per trillion) and a fern spore spike, suggesting that a bolide impact was the cause. Eastern North American dinosaurian diversity reached a stable maximum less than 100,000 years after the boundary, marking the establishment of dinosaur-dominated communities that prevailed for the next 135 million years.",
    url = "https://doi.org/10.1126/science.1065522",
    doi = "10.1126/science.1065522",
    openalex = "W2107051375",
    references = "doi1010160031018295001719, doi101126science22546661030, doi101126science3616622, doi1023073514751, doi105860choice332752, doi107312lock90868"
}

The debate on avian ancestry: phylogeny, function, and fossils / Lawrence M. Witmer -- Cladistic approaches to the relationships of birds to other theropod dinosaurs / James M. Clark, Mark A. Norell and Peter J. Makovicky -- The enigmatic birdlike dinosaur Avimimus portentosus: comments and a pictorial atlas / Patricia Vickers-Rich, Luis M. Chiappe and Sergei Kurzanov -- The Cretaceous short-armed Alvarezsauridae: Mononykus and its kin / Luis M. Chiappe, Mark A. Norell and James M. Clark -- Alvarezsaurid relationships reconsidered / Fernando E. Novas and Diego Pol -- Archaeopterygidae (Upper Jurassic of Germany) / Andrzej Elzanowski -- The discovery and study of Mesozoic birds in China / Zhou Zhonghe and Hou Lianhai -- Sinornis santensis (Aves: Enantiornithes) from the early Cretaceous of northeastern China / Paul C. Sereno, Rao Chenggang and Li Jianjun -- The birds from the Lower Cretaceous of Las Hoyas (Province of Cuenca, Spain) / Jose L. Sanz... [et al.] -- Nogueromis gonzalezi (Aves: Ornithothoraces) from the early Cretaceous of Spain / Luis M. Chiappe and Antonio Lacasa-Ruiz -- Skeletal morphology and systematics of the Cretaceous Euenantiornithes (Ornithothoraces: Enantiornithes) / Luis M. Chiappe and Cyril A. Walker -- Vorona berivotrensis, a primitive bird from the late Cretaceous of Madagascar / Catherine A. Forster... [et al.] -- Osteology of the flightless Patagopteryx deferrariisi from the late Cretaceous of Patagonia (Argentina) / Luis M. Chiappe -- Enaliornis, an early Cretaceous hesperornithiform bird from England, with comments on other Hesperornithiformes / Peter M. Galton and Larry D. Martin -- The Mesozoic radiation of Neornithes / Sylvia Hope -- A review of avian Mesozoic fossil feathers / Alexander W.A. Kellner -- The track record of Mesozoic birds and pterosaurs: an ichnological and paleoecological perspective / Martin G. Lockley and Emma C. Rainforth -- Bone microstructure of early birds / Anusuya Chinsamy -- Locomotor evolution on the line to modern birds / Stephen M. Gatesy -- Basal bird phylogeny: problems and solutions / Luis M. Chiappe.

@article{doi1016660022336020030770822mbatho20co2,
    author = "Clarke, Julia",
    title = "Mesozoic Birds: Above the Heads of Dinosaurs",
    year = "2003",
    journal = "Journal of Paleontology",
    abstract = "The debate on avian ancestry: phylogeny, function, and fossils / Lawrence M. Witmer -- Cladistic approaches to the relationships of birds to other theropod dinosaurs / James M. Clark, Mark A. Norell and Peter J. Makovicky -- The enigmatic birdlike dinosaur Avimimus portentosus: comments and a pictorial atlas / Patricia Vickers-Rich, Luis M. Chiappe and Sergei Kurzanov -- The Cretaceous short-armed Alvarezsauridae: Mononykus and its kin / Luis M. Chiappe, Mark A. Norell and James M. Clark -- Alvarezsaurid relationships reconsidered / Fernando E. Novas and Diego Pol -- Archaeopterygidae (Upper Jurassic of Germany) / Andrzej Elzanowski -- The discovery and study of Mesozoic birds in China / Zhou Zhonghe and Hou Lianhai -- Sinornis santensis (Aves: Enantiornithes) from the early Cretaceous of northeastern China / Paul C. Sereno, Rao Chenggang and Li Jianjun -- The birds from the Lower Cretaceous of Las Hoyas (Province of Cuenca, Spain) / Jose L. Sanz... [et al.] -- Nogueromis gonzalezi (Aves: Ornithothoraces) from the early Cretaceous of Spain / Luis M. Chiappe and Antonio Lacasa-Ruiz -- Skeletal morphology and systematics of the Cretaceous Euenantiornithes (Ornithothoraces: Enantiornithes) / Luis M. Chiappe and Cyril A. Walker -- Vorona berivotrensis, a primitive bird from the late Cretaceous of Madagascar / Catherine A. Forster... [et al.] -- Osteology of the flightless Patagopteryx deferrariisi from the late Cretaceous of Patagonia (Argentina) / Luis M. Chiappe -- Enaliornis, an early Cretaceous hesperornithiform bird from England, with comments on other Hesperornithiformes / Peter M. Galton and Larry D. Martin -- The Mesozoic radiation of Neornithes / Sylvia Hope -- A review of avian Mesozoic fossil feathers / Alexander W.A. Kellner -- The track record of Mesozoic birds and pterosaurs: an ichnological and paleoecological perspective / Martin G. Lockley and Emma C. Rainforth -- Bone microstructure of early birds / Anusuya Chinsamy -- Locomotor evolution on the line to modern birds / Stephen M. Gatesy -- Basal bird phylogeny: problems and solutions / Luis M. Chiappe.",
    url = "https://doi.org/10.1666/0022-3360(2003)077<0822:mbatho>2.0.co;2",
    doi = "10.1666/0022-3360(2003)077<0822:mbatho>2.0.co;2",
    openalex = "W4301871956",
    references = "doi101038292051a0"
}

Fragmentary theropod remains from the Upper Jurassic (Kimmeridgian) of Guimarota, Portugal, represent a new taxon of theropod dinosaurs, Aviatyrannis jurassica gen. et sp. nov. Together with Stokesosaurus from the Morrison Formation of North America, Aviatyrannis represents the oldest known tyrannosauroid, indicating that tyrannosauroid origins may be found in the Middle–Late Jurassic of Europe/North America. Furthermore, current evidence suggests that early tyrannosaurs were rather small animals, which is in general accordance with their origin amongst the generally rather small coelurosaurs.

@article{rauhut2003a,
    author = "Rauhut, Oliver W. M.",
    title = "A tyrannosauroid dinosaur from the Upper Jurassic of Portugal",
    year = "2003",
    journal = "Palaeontology",
    abstract = "Fragmentary theropod remains from the Upper Jurassic (Kimmeridgian) of Guimarota, Portugal, represent a new taxon of theropod dinosaurs, Aviatyrannis jurassica gen. et sp. nov. Together with Stokesosaurus from the Morrison Formation of North America, Aviatyrannis represents the oldest known tyrannosauroid, indicating that tyrannosauroid origins may be found in the Middle–Late Jurassic of Europe/North America. Furthermore, current evidence suggests that early tyrannosaurs were rather small animals, which is in general accordance with their origin amongst the generally rather small coelurosaurs.",
    url = "https://doi.org/10.1111/1475-4983.00325",
    doi = "10.1111/1475-4983.00325",
    number = "5",
    openalex = "W2138498181",
    pages = "903-910",
    volume = "46"
}

Dinosaur traces are well known from the western United States in the Colorado Plateau region (Utah, Colorado, New Mexico, and Arizona). Utah contains the greatest abundance of known and documented dinosaur footprints and trackways. Far less well known, however, is the occurrence and distribution of dinosaur footprint-bearing horizons in Wyoming. Scientific studies over the past 10 years have shown that three of the four Middle and Upper Jurassic formations in northern Wyoming contain dinosaur footprints. Two of the footprint-bearing horizons are located in geologic intervals that were once thought to have been deposited in offshore to nearshore marine settings and represent rare North American examples of Middle Jurassic (Bajocian and Bathonian) dinosaur remains. Some of these new Wyoming sites can be correlated to known dinosaur footprint-bearing horizons or intervals in Utah. Wyoming has a great potential for additional discoveries of new dinosaur footprint-bearing horizons, and further prospecting and study is warranted and will ultimately lead to a much better understanding of the geographic distribution and behavior of the potential footprint-makers.

@article{doi10108010420940490428823,
    author = "Kvale, Erik P. and Mickelson, Debra L. and Hasiotis, Stephen T. and Johnson, Gary D.",
    title = "The History of Dinosaur Footprint Discoveries in Wyoming with Emphasis on the Bighorn Basin",
    year = "2004",
    journal = "Ichnos/Ichnos : an international journal for plant and animal traces",
    abstract = "Dinosaur traces are well known from the western United States in the Colorado Plateau region (Utah, Colorado, New Mexico, and Arizona). Utah contains the greatest abundance of known and documented dinosaur footprints and trackways. Far less well known, however, is the occurrence and distribution of dinosaur footprint-bearing horizons in Wyoming. Scientific studies over the past 10 years have shown that three of the four Middle and Upper Jurassic formations in northern Wyoming contain dinosaur footprints. Two of the footprint-bearing horizons are located in geologic intervals that were once thought to have been deposited in offshore to nearshore marine settings and represent rare North American examples of Middle Jurassic (Bajocian and Bathonian) dinosaur remains. Some of these new Wyoming sites can be correlated to known dinosaur footprint-bearing horizons or intervals in Utah. Wyoming has a great potential for additional discoveries of new dinosaur footprint-bearing horizons, and further prospecting and study is warranted and will ultimately lead to a much better understanding of the geographic distribution and behavior of the potential footprint-makers.",
    url = "https://doi.org/10.1080/10420940490428823",
    doi = "10.1080/10420940490428823",
    openalex = "W1969074631",
    references = "doi1010160031018274900248, doi1010160031018285900070, doi101111j136530911988tb01248x, doi101111j136530911997tb01531x, doi101130gsab43383, doi1016690883135120010160233mjbabd20co2, doi105860choice332752, doi107312lock90868, foster1995tridactyl, kvaleNonepaleoenvironments, openalexw1533729705, openalexw1603783104"
}

Abstract A comprehensive taphonomic analysis has yielded a novel interpretation for one of the most famous dinosaur quarries in the world. The Cleveland-Lloyd Dinosaur Quarry (CLDQ) traditionally has been interpreted as an attritional predator trap. This scenario is based largely on a remarkable 3:1 predator:prey ratio, dominated by the remains of the theropod Allosaurus fragilis. This study addresses the taphonomy of CLDQ by combining analyses of fossils and entombing sediments along with putative modern analogues. Thousands of bones have been excavated from CLDQ, representing at least 70 individual dinosaurs from a minimum of nine genera. The fossils occur in a 1-m-thick fine-grained calcareous mudstone interpreted as a floodplain ephemeral-pond deposit. The bones show minimal carnivore modification and surface weathering, whereas approximately 1/3 of the elements studied possess pre-depositional fractures and evidence of abrasion. The vast majority of elements are found horizontal to subhorizontal, wit...

@article{doi102110palo2003p0322,
    author = "Gates, Tim",
    title = "The Late Jurassic Cleveland-Lloyd Dinosaur Quarry as a Drought-Induced Assemblage",
    year = "2005",
    journal = "Palaios",
    abstract = "Abstract A comprehensive taphonomic analysis has yielded a novel interpretation for one of the most famous dinosaur quarries in the world. The Cleveland-Lloyd Dinosaur Quarry (CLDQ) traditionally has been interpreted as an attritional predator trap. This scenario is based largely on a remarkable 3:1 predator:prey ratio, dominated by the remains of the theropod Allosaurus fragilis. This study addresses the taphonomy of CLDQ by combining analyses of fossils and entombing sediments along with putative modern analogues. Thousands of bones have been excavated from CLDQ, representing at least 70 individual dinosaurs from a minimum of nine genera. The fossils occur in a 1-m-thick fine-grained calcareous mudstone interpreted as a floodplain ephemeral-pond deposit. The bones show minimal carnivore modification and surface weathering, whereas approximately 1/3 of the elements studied possess pre-depositional fractures and evidence of abrasion. The vast majority of elements are found horizontal to subhorizontal, wit...",
    url = "https://doi.org/10.2110/palo.2003.p03-22",
    doi = "10.2110/palo.2003.p03-22",
    openalex = "W2173872034",
    references = "crossref1976allosaurus, doi1010029780470344903, doi1010160278416583900089, doi1010160305440388900817, doi101017s0094837300005820, doi10102994jb01889, doi102113gsrocky8specialpaper11, doi105860choice300309, doi105962bhlpart22969, hirsch1989upper, openalexw1576457137"
}

Abstract: Ornitholestes hermanni is a Late Jurassic theropod dinosaur from North America. This kinematic study of Ornitholestes uses manual manipulations of forelimb casts to determine range of motion. The manual phalanges of the O. hermanni holotype, previously unidentified, are here identified as phalanges I-1, I-2 (ungual), II-2 and II-3 (ungual). At all represented manual joints, hyperextensibility is small or absent, whereas flexion is strong, as in most other theropods. The elbow can be strongly flexed beyond a right angle. When data on range of forelimb motion in Ornitholestes are added to such data from other theropods, high elbow flexion is present in maniraptoriform coelurosaurs but not in basal theropods. Forelimb functions requiring strong elbow flexion (such as holding objects to the chest, or tucking the forearms in for their protection or to reduce wind resistance or heat loss) were therefore available to maniraptoriform coelurosaurs but not to basal theropods.

@article{doi101111j14754983200600585x,
    author = "Senter, Phil",
    title = "FORELIMB FUNCTION IN ORNITHOLESTES HERMANNI OSBORN (DINOSAURIA, THEROPODA)",
    year = "2006",
    journal = "Palaeontology",
    abstract = "Abstract: Ornitholestes hermanni is a Late Jurassic theropod dinosaur from North America. This kinematic study of Ornitholestes uses manual manipulations of forelimb casts to determine range of motion. The manual phalanges of the O. hermanni holotype, previously unidentified, are here identified as phalanges I-1, I-2 (ungual), II-2 and II-3 (ungual). At all represented manual joints, hyperextensibility is small or absent, whereas flexion is strong, as in most other theropods. The elbow can be strongly flexed beyond a right angle. When data on range of forelimb motion in Ornitholestes are added to such data from other theropods, high elbow flexion is present in maniraptoriform coelurosaurs but not in basal theropods. Forelimb functions requiring strong elbow flexion (such as holding objects to the chest, or tucking the forearms in for their protection or to reduce wind resistance or heat loss) were therefore available to maniraptoriform coelurosaurs but not to basal theropods.",
    url = "https://doi.org/10.1111/j.1475-4983.2006.00585.x",
    doi = "10.1111/j.1475-4983.2006.00585.x",
    openalex = "W1509107308",
    references = "crossref1976allosaurus, doi10103832884, doi101139e93187, doi1012060003008220023810001nsomzt20co2, doi102475ajss31695411, doi105281zenodo16171435, doi105860choice393984, doi105860choice434677, openalexw2788234611, openalexw3190253505"
}

Abstract: A new genus and species of diplodocid sauropod (Sauropoda, Diplodocoidea), Australodocus bohetii, is described. The type material from the Upper Jurassic (Tithonian) Tendaguru Beds of Tanzania, East Africa, consists of two successive mid‐cervical vertebrae. These vertebrae do not show the extreme elongation of the cervical vertebrae that is diagnostic for Tornieria, and, apart from proportional differences, exhibit four autapomorphic characters not seen in other diplodocids: (1) pleurocoel weakly developed; (2) ridge posterolateral to the anterior condyle strongly posteroventrally orientated; (3) triangular pneumatic cavity ventral to the prezygapophysis, enclosed by the lateral ramus of the centroprezygapophyseal lamina and an anteriorly extended prezygodiapophyseal lamina; and (4) prominent prezygapophyseal process pointed, laterally keeled and surpassing the prezygapophysis anteriorly. Australodocus bohetii is the second diplodocid known from Tendaguru, and thereby the second diplodocid known from Gondwana. This impedes the customary reference of isolated East African diplodocid material to Tornieria, which can now only be assigned to Diplodocidae indet. The find supports previously proposed vicariance models of diplodocid palaeobiogeography.

@article{doi101111j14754983200700652x,
    author = "Remes, Kristian",
    title = "A SECOND GONDWANAN DIPLODOCID DINOSAUR FROM THE UPPER JURASSIC TENDAGURU BEDS OF TANZANIA, EAST AFRICA",
    year = "2007",
    journal = "Palaeontology",
    abstract = "Abstract: A new genus and species of diplodocid sauropod (Sauropoda, Diplodocoidea), Australodocus bohetii, is described. The type material from the Upper Jurassic (Tithonian) Tendaguru Beds of Tanzania, East Africa, consists of two successive mid‐cervical vertebrae. These vertebrae do not show the extreme elongation of the cervical vertebrae that is diagnostic for Tornieria, and, apart from proportional differences, exhibit four autapomorphic characters not seen in other diplodocids: (1) pleurocoel weakly developed; (2) ridge posterolateral to the anterior condyle strongly posteroventrally orientated; (3) triangular pneumatic cavity ventral to the prezygapophysis, enclosed by the lateral ramus of the centroprezygapophyseal lamina and an anteriorly extended prezygodiapophyseal lamina; and (4) prominent prezygapophyseal process pointed, laterally keeled and surpassing the prezygapophysis anteriorly. Australodocus bohetii is the second diplodocid known from Tendaguru, and thereby the second diplodocid known from Gondwana. This impedes the customary reference of isolated East African diplodocid material to Tornieria, which can now only be assigned to Diplodocidae indet. The find supports previously proposed vicariance models of diplodocid palaeobiogeography.",
    url = "https://doi.org/10.1111/j.1475-4983.2007.00652.x",
    doi = "10.1111/j.1475-4983.2007.00652.x",
    openalex = "W2093488609",
    references = "openalexw605949302, schuchert1934the"
}

Synopsis Measurements of Middle Jurassic tridactyl dinosaur tracks from the Bathonian, Lealt Shale, Valtos Sandstone, Duntulm and Kilmaluag formations of the Isle of Skye, UK, are compared to the same measurements taken for dinosaur footprints from the Bajocian, Gypsum Spring and the Bathonian, Sundance Formation of the Bighorn Basin, Wyoming, USA. Principal component analysis of the data suggests that the smaller footprints from the Valtos Sandstone and Kilmaluag formations are indistinguishable from the footprints of the Sundance Formation. The single footprint from the Lealt Shale Formation is similar to the larger footprints from the Valtos Sandstone Formation. The footprints from the Duntulm and Gypsum Springs formations form distinct groupings from all other footprints. Four different groupings of dinosaur footprints can be recognized from the principal component analysis that may represent at least four different types of dinosaur.

@article{doi101144sjg44020139,
    author = "Clark, Neil D. L. and Brett-Surman, Michael K.",
    title = "A comparison between dinosaur footprints from the Middle Jurassic of the Isle of Skye, Scotland, UK, and Shell, Wyoming, USA",
    year = "2008",
    journal = "Scottish Journal of Geology",
    abstract = "Synopsis Measurements of Middle Jurassic tridactyl dinosaur tracks from the Bathonian, Lealt Shale, Valtos Sandstone, Duntulm and Kilmaluag formations of the Isle of Skye, UK, are compared to the same measurements taken for dinosaur footprints from the Bajocian, Gypsum Spring and the Bathonian, Sundance Formation of the Bighorn Basin, Wyoming, USA. Principal component analysis of the data suggests that the smaller footprints from the Valtos Sandstone and Kilmaluag formations are indistinguishable from the footprints of the Sundance Formation. The single footprint from the Lealt Shale Formation is similar to the larger footprints from the Valtos Sandstone Formation. The footprints from the Duntulm and Gypsum Springs formations form distinct groupings from all other footprints. Four different groupings of dinosaur footprints can be recognized from the principal component analysis that may represent at least four different types of dinosaur.",
    url = "https://doi.org/10.1144/sjg44020139",
    doi = "10.1144/sjg44020139",
    openalex = "W2059387217",
    references = "doi10108010420940490428823"
}

Dinosaur tracks in Portugal are known from Bajocian-Bathonian (Jurassic) through middle Cenomanian (Cretaceous) rocks. The Portuguese track record includes two outstanding Middle Jurassic track sites both in Central W Portugal: the Vale de Meios track site, showing dozens of parallel theropod trackways, and the Galinha site, where several long sauropod trackways can be seen. There are two other major areas with important dinosaur track sites: SW Algarve (S Portugal), Lower Cretaceous, and the Sesimbra region (Central W Portugal), Upper Jurassic-Lower Cretaceous. Huge track sites such as the Vale de Meios and Galinha sites can not be excavated and removed into museums; therefore, they must be preserved in situ, to be studied and visited in their original geological context. Track sites such as these are important not only for their scientific, ichnological, significance; they are also valuable for science popularization and to stimulate public inter - est for the preservation of the geological/palaeontological heritage. In Portugal, in 1996 and 1997, five dinosaur track sites have been declared natural monuments. In such sites it is possible to teach and show Palaeontology, as well as other aspects of Earth sciences in their original geological context, to children from different school levels and to a broad public with dif- ferent scientific backgrounds. Educational programmes for school children and the general public are paramount in order to elucidate them about dinosaurs and their tracks, but also to improve their attitude towards the scientific and cultural value of this palaeontological ichnoheritage. Educational activities are essential to the success of geoconservation. They boost public awareness, which, in turn, is fundamental for the protection and valorisation of the geological and palaeontological heritage. When local communities are conscious of the scientific and cultural value of the natural heritage in their home region they become proud of it and this fact dramatically increases the odds of its effective protection. Nevertheless, up until now the Galinha track site is the only Portuguese track site prepared to receive visitors and to offer them palaeontological educational programmes.

@article{openalexw2182538351,
    author = "dos Santos, Vanda Faria and da Silva, Carlos Marques and Rodrigues, Luís Azevedo",
    title = "Dinosaur track sites from Portugal: Scientific and cultural signifi- cance",
    year = "2008",
    journal = "reroDoc Digital Library",
    abstract = "Dinosaur tracks in Portugal are known from Bajocian-Bathonian (Jurassic) through middle Cenomanian (Cretaceous) rocks. The Portuguese track record includes two outstanding Middle Jurassic track sites both in Central W Portugal: the Vale de Meios track site, showing dozens of parallel theropod trackways, and the Galinha site, where several long sauropod trackways can be seen. There are two other major areas with important dinosaur track sites: SW Algarve (S Portugal), Lower Cretaceous, and the Sesimbra region (Central W Portugal), Upper Jurassic-Lower Cretaceous. Huge track sites such as the Vale de Meios and Galinha sites can not be excavated and removed into museums; therefore, they must be preserved in situ, to be studied and visited in their original geological context. Track sites such as these are important not only for their scientific, ichnological, significance; they are also valuable for science popularization and to stimulate public inter - est for the preservation of the geological/palaeontological heritage. In Portugal, in 1996 and 1997, five dinosaur track sites have been declared natural monuments. In such sites it is possible to teach and show Palaeontology, as well as other aspects of Earth sciences in their original geological context, to children from different school levels and to a broad public with dif- ferent scientific backgrounds. Educational programmes for school children and the general public are paramount in order to elucidate them about dinosaurs and their tracks, but also to improve their attitude towards the scientific and cultural value of this palaeontological ichnoheritage. Educational activities are essential to the success of geoconservation. They boost public awareness, which, in turn, is fundamental for the protection and valorisation of the geological and palaeontological heritage. When local communities are conscious of the scientific and cultural value of the natural heritage in their home region they become proud of it and this fact dramatically increases the odds of its effective protection. Nevertheless, up until now the Galinha track site is the only Portuguese track site prepared to receive visitors and to offer them palaeontological educational programmes.",
    openalex = "W2182538351",
    references = "doi10108010420940490428823"
}

Abstract. The well-known Late Jurassic to Early Cretaceous Tendaguru Beds of southern Tanzania have yielded fossil plant remains, invertebrates and vertebrates, notably dinosaurs, of exceptional scientific importance. Based on data of the German-Tanzanian Tendaguru Expedition 2000 and previous studies, and in accordance with the international stratigraphic guide, we raise the Tendaguru Beds to formational rank and recognise six members (from bottom to top): Lower Dinosaur Member, Nerinella Member, Middle Dinosaur Member, Indotrigonia africana Member, Upper Dinosaur Member, and Rutitrigonia bornhardti-schwarzi Member. We characterise and discuss each member in detail in terms of derivation of name, definition of a type section, distribution, thickness, lithofacies, boundaries, palaeontology, and age. The age of the whole formation apparently ranges at least from the middle Oxfordian to the Valanginian through Hauterivian or possibly Aptian. The Tendaguru Formation constitutes a cyclic sedimentary succession, consisting of three marginal marine, sandstone-dominated depositional units and three predominantly coastal to tidal plain, fine-grained depositional units with dinosaur remains. It represents four third-order sequences, which are composed of transgressive and highstand systems tracts. Sequence boundaries are represented by transgressive ravinement surfaces and maximum flooding surfaces. In a more simple way, the depositional sequences can be subdivided into transgressive and regressive sequences/systems tracts. Whereas the transgressive systems tracts are mainly represented by shallow marine shoreface, tidal channel and sand bar sandstones, the regressive systems tracts predominantly consist of shallow tidal channel, tidal flat, and marginal lagoonal to supratidal deposits. doi: 10.1002/mmng.200900004

@article{doi101002mmng200900004,
    author = "Bussert, Robert and Heinrich, Wolf‐Dieter and Aberhan, M.",
    title = "The Tendaguru Formation (Late Jurassic to Early Cretaceous, southern Tanzania): definition, palaeoenvironments, and sequence stratigraphy",
    year = "2009",
    journal = "Fossil Record",
    abstract = "Abstract. The well-known Late Jurassic to Early Cretaceous Tendaguru Beds of southern Tanzania have yielded fossil plant remains, invertebrates and vertebrates, notably dinosaurs, of exceptional scientific importance. Based on data of the German-Tanzanian Tendaguru Expedition 2000 and previous studies, and in accordance with the international stratigraphic guide, we raise the Tendaguru Beds to formational rank and recognise six members (from bottom to top): Lower Dinosaur Member, Nerinella Member, Middle Dinosaur Member, Indotrigonia africana Member, Upper Dinosaur Member, and Rutitrigonia bornhardti-schwarzi Member. We characterise and discuss each member in detail in terms of derivation of name, definition of a type section, distribution, thickness, lithofacies, boundaries, palaeontology, and age. The age of the whole formation apparently ranges at least from the middle Oxfordian to the Valanginian through Hauterivian or possibly Aptian. The Tendaguru Formation constitutes a cyclic sedimentary succession, consisting of three marginal marine, sandstone-dominated depositional units and three predominantly coastal to tidal plain, fine-grained depositional units with dinosaur remains. It represents four third-order sequences, which are composed of transgressive and highstand systems tracts. Sequence boundaries are represented by transgressive ravinement surfaces and maximum flooding surfaces. In a more simple way, the depositional sequences can be subdivided into transgressive and regressive sequences/systems tracts. Whereas the transgressive systems tracts are mainly represented by shallow marine shoreface, tidal channel and sand bar sandstones, the regressive systems tracts predominantly consist of shallow tidal channel, tidal flat, and marginal lagoonal to supratidal deposits. doi: 10.1002/mmng.200900004",
    url = "https://doi.org/10.1002/mmng.200900004",
    doi = "10.1002/mmng.200900004",
    openalex = "W2011013054",
    references = "doi1010029781444313710, doi101002mmng20010040113, doi101002mmng4860040113, doi101016001670379290334f, doi1010160037073895900225, doi101016s0031018200002297, doi101306m26490c6, doi1015468gbdyof, doi1018814epiiugs2004v27i2002, doi102110pec87410241, doi102110pec88010071, kahlert1999die, openalexw2687631996, openalexw605949302, schuchert1934the"
}

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"
}

The well-known Late Jurassic to Early Cretaceous Tendaguru Beds of southern Tanzania have yielded fossil plant remains, invertebrates and vertebrates, notably dinosaurs, of exceptional scientific importance. Based on data of the German-Tanzanian Tendaguru Expedition 2000 and previous studies, and in accordance with the international stratigraphic guide, we raise the Tendaguru Beds to formational rank and recognise six members (from bottom to top): Lower Dinosaur Member, Nerinella Member, Middle Dinosaur Member, Indotrigonia africana Member, Upper Dinosaur Member, and Rutitrigonia bornhardti-schwarzi Member. We characterise and discuss each member in detail in terms of derivation of name, definition of a type section, distribution, thickness, lithofacies, boundaries, palaeontology, and age. The age of the whole formation apparently ranges at least from the middle Oxfordian to the Valanginian through Hauterivian or possibly Aptian. The Tendaguru Formation constitutes a cyclic sedimentary succession, consisting of three marginal marine, sandstone-dominated depositional units and three predominantly coastal to tidal plain, fine-grained depositional units with dinosaur remains. It represents four third-order sequences, which are composed of transgressive and highstand systems tracts. Sequence boundaries are represented by transgressive ravinement surfaces and maximum flooding surfaces. In a more simple way, the depositional sequences can be subdivided into transgressive and regressive sequences/systems tracts. Whereas the transgressive systems tracts are mainly represented by shallow marine shoreface, tidal channel and sand bar sandstones, the regressive systems tracts predominantly consist of shallow tidal channel, tidal flat, and marginal lagoonal to supratidal deposits. doi: 10.1002/mmng.200900004

@article{doi105194fr121412009,
    author = "Bussert, Robert and Heinrich, Wolf‐Dieter and Aberhan, M.",
    title = "The Tendaguru Formation (Late Jurassic to Early Cretaceous, southern Tanzania): definition, palaeoenvironments, and sequence stratigraphy",
    year = "2009",
    journal = "Fossil record",
    abstract = "The well-known Late Jurassic to Early Cretaceous Tendaguru Beds of southern Tanzania have yielded fossil plant remains, invertebrates and vertebrates, notably dinosaurs, of exceptional scientific importance. Based on data of the German-Tanzanian Tendaguru Expedition 2000 and previous studies, and in accordance with the international stratigraphic guide, we raise the Tendaguru Beds to formational rank and recognise six members (from bottom to top): Lower Dinosaur Member, Nerinella Member, Middle Dinosaur Member, Indotrigonia africana Member, Upper Dinosaur Member, and Rutitrigonia bornhardti-schwarzi Member. We characterise and discuss each member in detail in terms of derivation of name, definition of a type section, distribution, thickness, lithofacies, boundaries, palaeontology, and age. The age of the whole formation apparently ranges at least from the middle Oxfordian to the Valanginian through Hauterivian or possibly Aptian. The Tendaguru Formation constitutes a cyclic sedimentary succession, consisting of three marginal marine, sandstone-dominated depositional units and three predominantly coastal to tidal plain, fine-grained depositional units with dinosaur remains. It represents four third-order sequences, which are composed of transgressive and highstand systems tracts. Sequence boundaries are represented by transgressive ravinement surfaces and maximum flooding surfaces. In a more simple way, the depositional sequences can be subdivided into transgressive and regressive sequences/systems tracts. Whereas the transgressive systems tracts are mainly represented by shallow marine shoreface, tidal channel and sand bar sandstones, the regressive systems tracts predominantly consist of shallow tidal channel, tidal flat, and marginal lagoonal to supratidal deposits. doi: 10.1002/mmng.200900004",
    url = "https://doi.org/10.5194/fr-12-141-2009",
    doi = "10.5194/fr-12-141-2009",
    openalex = "W4239644658",
    references = "doi101002mmng4860040113, schuchert1934the"
}

@misc{brinkman2010the,
    author = "Brinkman, Paul D.",
    title = "The Second Jurassic Dinosaur Rush",
    year = "2010",
    url = "https://doi.org/10.7208/chicago/9780226074733.001.0001",
    doi = "10.7208/chicago/9780226074733.001.0001",
    openalex = "W4250846739"
}

Stegosaurus armatus Marsh 1877, based on a partial tail and a very large dermal plate from the Morrison Formation (Late Jurassic) of Morrison, Wyoming, USA, is a nomen dubium. Valid Morrison stegosaur species (with possible autapomorphies, dermal “armor” considered if present), with most holotypes consisting of a disarticulated partial postcranial skeleton at most, include: Hypsirhophus discurus Cope 1878 (characters of incomplete vertebrae, a dorsal and a caudal; Garden Park near Cañon City, Colorado); Stegosaurus ungulatus Marsh 1879 (half skeleton with partial skull; three pairs of small flat dermal spines adjacent to terminal tail spikes; Quarry 12, Como Bluff near Como station, Wyoming; syntype is holotype of S. duplex Marsh 1887, half skeleton lacking armor; Quarry 11, Como Bluff); Diracodon laticeps Marsh 1881b (just partial dentaries with few teeth, diastema between predentary and tooth 1; Quarry 13, Como Bluff); Stegosaurus sulcatus Marsh 1887 (pair of?tail spikes with greatly enlarged base; Quarry 13, Como Bluff); S. longispinus Gilmore 1914 (characters of distal caudal vertebrae, tail spikes: two pairs, sub-equal bases, transversely flattened, very elongate; Alcova, Wyoming); and Hesperosaurus mjosi Carpenter, Miles & Cloward, 2001 (?Stegosaurus mjosi; partial articulated skeleton with skull, no limbs, several plesiomorphic and autapomorphic characters, dorsal plates longer than tall; Wyoming). However, the well known valid nominal species, S. stenops Marsh 1887 (12 autapomorphies, three alternating flat plates adjacent to terminal tail spikes; Garden Park), is based on a virtually complete articulated skeleton lacking only the terminal caudal vertebrae and first pair of tail spikes. It includes 17 dermal plates, is still exposed as preserved on the block, and is the current basis for Stegosaurus. The International Commission on Zoological Nomenclature (ICZN) will be petitioned to designate S. stenops Marsh 1887 as the new type species of Stegosaurus Marsh 1877 in order to conserve Stegosauria Marsh 1877 and Stegosauridae Marsh 1880 (also Stegosauroidea, Stegosaurinae).

@article{doi101007s0001501000224,
    author = "Galton, Peter M.",
    title = "Species of plated dinosaur Stegosaurus (Morrison Formation, Late Jurassic) of western USA: new type species designation needed",
    year = "2010",
    journal = "Swiss Journal of Geosciences",
    abstract = "Stegosaurus armatus Marsh 1877, based on a partial tail and a very large dermal plate from the Morrison Formation (Late Jurassic) of Morrison, Wyoming, USA, is a nomen dubium. Valid Morrison stegosaur species (with possible autapomorphies, dermal “armor” considered if present), with most holotypes consisting of a disarticulated partial postcranial skeleton at most, include: Hypsirhophus discurus Cope 1878 (characters of incomplete vertebrae, a dorsal and a caudal; Garden Park near Cañon City, Colorado); Stegosaurus ungulatus Marsh 1879 (half skeleton with partial skull; three pairs of small flat dermal spines adjacent to terminal tail spikes; Quarry 12, Como Bluff near Como station, Wyoming; syntype is holotype of S. duplex Marsh 1887, half skeleton lacking armor; Quarry 11, Como Bluff); Diracodon laticeps Marsh 1881b (just partial dentaries with few teeth, diastema between predentary and tooth 1; Quarry 13, Como Bluff); Stegosaurus sulcatus Marsh 1887 (pair of?tail spikes with greatly enlarged base; Quarry 13, Como Bluff); S. longispinus Gilmore 1914 (characters of distal caudal vertebrae, tail spikes: two pairs, sub-equal bases, transversely flattened, very elongate; Alcova, Wyoming); and Hesperosaurus mjosi Carpenter, Miles \& Cloward, 2001 (?Stegosaurus mjosi; partial articulated skeleton with skull, no limbs, several plesiomorphic and autapomorphic characters, dorsal plates longer than tall; Wyoming). However, the well known valid nominal species, S. stenops Marsh 1887 (12 autapomorphies, three alternating flat plates adjacent to terminal tail spikes; Garden Park), is based on a virtually complete articulated skeleton lacking only the terminal caudal vertebrae and first pair of tail spikes. It includes 17 dermal plates, is still exposed as preserved on the block, and is the current basis for Stegosaurus. The International Commission on Zoological Nomenclature (ICZN) will be petitioned to designate S. stenops Marsh 1887 as the new type species of Stegosaurus Marsh 1877 in order to conserve Stegosauria Marsh 1877 and Stegosauridae Marsh 1880 (also Stegosauroidea, Stegosaurinae).",
    url = "https://doi.org/10.1007/s00015-010-0022-4",
    doi = "10.1007/s00015-010-0022-4",
    openalex = "W2090448514",
    references = "crossref1998dinosaurs, doi101007s0001501000206, doi101007s0001501000242"
}

@article{mateus2010a,
    author = "Mateus, Octávio and Milàn, Jesper",
    title = "A diverse Upper Jurassic dinosaur ichnofauna from central-west Portugal",
    year = "2010",
    journal = "Lethaia",
    url = "https://doi.org/10.1111/j.1502-3931.2009.00190.x",
    doi = "10.1111/j.1502-3931.2009.00190.x",
    number = "2",
    openalex = "W2105513065",
    pages = "245-257",
    volume = "43",
    references = "doi1010079789400904095, doi101016016093279290032k, doi101016s075339690180015x, doi101038261129a0, doi10108010420949409386390, doi105860choice332752, doi105860choice435907, doi107312lock90868, openalexw114509570, openalexw3215902281"
}

Recent discoveries in Asia have greatly increased our understanding of the evolution of dinosaurs' integumentary structures, revealing a previously unexpected diversity of "protofeathers" and feathers. However, all theropod dinosaurs with preserved feathers reported so far are coelurosaurs. Evidence for filaments or feathers in noncoelurosaurian theropods is circumstantial and debated. Here we report an exceptionally preserved skeleton of a juvenile megalosauroid, Sciurumimus albersdoerferi n. gen., n. sp., from the Late Jurassic of Germany, which preserves a filamentous plumage at the tail base and on parts of the body. These structures are identical to the type 1 feathers that have been reported in some ornithischians, the basal tyrannosaur Dilong, the basal therizinosauroid Beipiaosaurus, and, probably, in the basal coelurosaur Sinosauropteryx. Sciurumimus albersdoerferi represents the phylogenetically most basal theropod that preserves direct evidence for feathers and helps close the gap between feathers reported in coelurosaurian theropods and filaments in ornithischian dinosaurs, further supporting the homology of these structures. The specimen of Sciurumimus is the most complete megalosauroid yet discovered and helps clarify significant anatomical details of this important basal theropod clade, such as the complete absence of the fourth digit of the manus. The dentition of this probably early-posthatchling individual is markedly similar to that of basal coelurosaurian theropods, indicating that coelurosaur occurrences based on isolated teeth should be used with caution.

@article{doi101073pnas1203238109,
    author = "Rauhut, Oliver W. M. and Foth, Christian and Tischlinger, Helmut and Norell, Mark A.",
    title = "Exceptionally preserved juvenile megalosauroid theropod dinosaur with filamentous integument from the Late Jurassic of Germany",
    year = "2012",
    journal = "Proceedings of the National Academy of Sciences",
    abstract = {Recent discoveries in Asia have greatly increased our understanding of the evolution of dinosaurs' integumentary structures, revealing a previously unexpected diversity of "protofeathers" and feathers. However, all theropod dinosaurs with preserved feathers reported so far are coelurosaurs. Evidence for filaments or feathers in noncoelurosaurian theropods is circumstantial and debated. Here we report an exceptionally preserved skeleton of a juvenile megalosauroid, Sciurumimus albersdoerferi n. gen., n. sp., from the Late Jurassic of Germany, which preserves a filamentous plumage at the tail base and on parts of the body. These structures are identical to the type 1 feathers that have been reported in some ornithischians, the basal tyrannosaur Dilong, the basal therizinosauroid Beipiaosaurus, and, probably, in the basal coelurosaur Sinosauropteryx. Sciurumimus albersdoerferi represents the phylogenetically most basal theropod that preserves direct evidence for feathers and helps close the gap between feathers reported in coelurosaurian theropods and filaments in ornithischian dinosaurs, further supporting the homology of these structures. The specimen of Sciurumimus is the most complete megalosauroid yet discovered and helps clarify significant anatomical details of this important basal theropod clade, such as the complete absence of the fourth digit of the manus. The dentition of this probably early-posthatchling individual is markedly similar to that of basal coelurosaurian theropods, indicating that coelurosaur occurrences based on isolated teeth should be used with caution.},
    url = "https://doi.org/10.1073/pnas.1203238109",
    doi = "10.1073/pnas.1203238109",
    openalex = "W2033273405",
    references = "benson2008a, carr1999craniofacial, crossref2013dinosaurs, doi101002jmor10382, doi101002sici1097010x199912152854291aidjez130co29, doi101007s001140090614x, doi101016jearscirev201004001, doi10103832884, doi101038nature02699, doi101038nature04511, doi101038nature07856, doi10108002724634199610011283, doi10108002724634199910011161, doi101111j10963642200600232x, doi101111j10963642200900569x, doi1011270077774920100125, doi101139e93179, doi10120600030082200635451andtfu20co2, doi1023072424244, doi105479si03629236110i"
}

Neosauropods are well represented in the Late Jurassic fossil record, both in Laurasia and Gondwana. Among Macronaria, Europasaurus represents one of the most basal forms of this group. In addition to its systematic importance, Europasaurus is also the first unequivocal dwarf sauropod from which adult and juvenile material is available. Despite the abundance of sauropods in the fossil record, early juvenile specimens are rare, limiting knowledge about sauropod ontogeny. Therefore, the great amount of material of Europasaurus provides an excellent opportunity to improve our knowledge on the early evolution of Macronaria, as well as to shed light on some morphological changes through ontogeny. The postcranial axial skeleton of sauropods is extremely modified with respect to the anatomy observed in its ancestors, the ‘prosauropods’, proving to be one of the most informative regions of the body. Here we provide a detailed description of the axial skeleton of Europasaurus, including adult and juvenile elements, discussing its systematic and ontogenetic importance. We also analyse the phylogenetic position of Europasaurus through a cladistic analysis using TNT, which retrieves this taxon in a basal position among Camarasauromorpha. Additionally, the presence/absence of discrete characters and the comparison of juvenile elements with adult specimens allowed us to recognize different morphological ontogenetic stages (MOS). Whereas early stages lack derived characters (e.g. spinodiapophyseal lamina and prespinal lamina on dorsal vertebrae), all derived characters (including autapomorphies) are present in late immature specimens. Therefore, while late immature specimens provide the same phylogenetic signal as adult specimens of Europasaurus, more immature stages are recovered in a basal position among sauropods. Finally, we apply the MOS to other maturity criteria (e.g. neurocentral closure, sexual maturity) in a search for a wider definition of maturity.

@article{doi101080147720192013764935,
    author = "Carballido, José Luis and Sander, P. Martin",
    title = "Postcranial axial skeleton of Europasaurus holgeri (Dinosauria, Sauropoda) from the Upper Jurassic of Germany: implications for sauropod ontogeny and phylogenetic relationships of basal Macronaria",
    year = "2013",
    journal = "Journal of Systematic Palaeontology",
    abstract = "Neosauropods are well represented in the Late Jurassic fossil record, both in Laurasia and Gondwana. Among Macronaria, Europasaurus represents one of the most basal forms of this group. In addition to its systematic importance, Europasaurus is also the first unequivocal dwarf sauropod from which adult and juvenile material is available. Despite the abundance of sauropods in the fossil record, early juvenile specimens are rare, limiting knowledge about sauropod ontogeny. Therefore, the great amount of material of Europasaurus provides an excellent opportunity to improve our knowledge on the early evolution of Macronaria, as well as to shed light on some morphological changes through ontogeny. The postcranial axial skeleton of sauropods is extremely modified with respect to the anatomy observed in its ancestors, the ‘prosauropods’, proving to be one of the most informative regions of the body. Here we provide a detailed description of the axial skeleton of Europasaurus, including adult and juvenile elements, discussing its systematic and ontogenetic importance. We also analyse the phylogenetic position of Europasaurus through a cladistic analysis using TNT, which retrieves this taxon in a basal position among Camarasauromorpha. Additionally, the presence/absence of discrete characters and the comparison of juvenile elements with adult specimens allowed us to recognize different morphological ontogenetic stages (MOS). Whereas early stages lack derived characters (e.g. spinodiapophyseal lamina and prespinal lamina on dorsal vertebrae), all derived characters (including autapomorphies) are present in late immature specimens. Therefore, while late immature specimens provide the same phylogenetic signal as adult specimens of Europasaurus, more immature stages are recovered in a basal position among sauropods. Finally, we apply the MOS to other maturity criteria (e.g. neurocentral closure, sexual maturity) in a search for a wider definition of maturity.",
    url = "https://doi.org/10.1080/14772019.2013.764935",
    doi = "10.1080/14772019.2013.764935",
    openalex = "W2076978806",
    references = "doi101002jez513, doi10108002724634199510011271, doi101098rspl18870117, doi101371journalpone0017114, doi1016660094837320080340247ositlb20co2, doi10167102724634200727350asoitp20co2, doi102475ajss31695411, doi103998mpub9690664, doi105860choice490282"
}

Titanosauriforms represent a diverse and globally distributed clade of neosauropod dinosaurs, but their inter-relationships remain poorly understood. Here we redescribe Lusotitan atalaiensis from the Late Jurassic Lourinhã Formation of Portugal, a taxon previously referred to Brachiosaurus. The lectotype includes cervical, dorsal, and caudal vertebrae, and elements from the forelimb, hindlimb, and pelvic girdle. Lusotitan is a valid taxon and can be diagnosed by six autapomorphies, including the presence of elongate postzygapophyses that project well beyond the posterior margin of the neural arch in anterior-to-middle caudal vertebrae. A new phylogenetic analysis, focused on elucidating the evolutionary relationships of basal titanosauriforms, is presented, comprising 63 taxa scored for 279 characters. Many of these characters are heavily revised or novel to our study, and a number of ingroup taxa have never previously been incorporated into a phylogenetic analysis. We treated quantitative characters as discrete and continuous data in two parallel analyses, and explored the effect of implied weighting. Although we recovered monophyletic brachiosaurid and somphospondylan sister clades within Titanosauriformes, their compositions were affected by alternative treatments of quantitative data and, especially, by the weighting of such data. This suggests that the treatment of quantitative data is important and the wrong decisions might lead to incorrect tree topologies. In particular, the diversity of Titanosauria was greatly increased by the use of implied weights. Our results support the generic separation of the contemporaneous taxa Brachiosaurus, Giraffatitan, and Lusotitan, with the latter recovered as either a brachiosaurid or the sister taxon to Titanosauriformes. Although Janenschia was recovered as a basal macronarian, outside Titanosauria, the sympatric Australodocus provides body fossil evidence for the pre-Cretaceous origin of titanosaurs. We recovered evidence for a sauropod with close affinities to the Chinese taxon Mamenchisaurus in the Late Jurassic Tendaguru beds of Africa, and present new information demonstrating the wider distribution of caudal pneumaticity within Titanosauria. The earliest known titanosauriform body fossils are from the late Oxfordian (Late Jurassic), although trackway evidence indicates a Middle Jurassic origin. Diversity increased throughout the Late Jurassic, and titanosauriforms did not undergo a severe extinction across the Jurassic/Cretaceous boundary, in contrast to diplodocids and non-neosauropods. Titanosauriform diversity increased in the Barremian and Aptian–Albian as a result of radiations of derived somphospondylans and lithostrotians, respectively, but there was a severe drop (up to 40%) in species numbers at, or near, the Albian/Cenomanian boundary, representing a faunal turnover whereby basal titanosauriforms were replaced by derived titanosaurs, although this transition occurred in a spatiotemporally staggered fashion.

@article{doi101111zoj12029,
    author = "Mannion, Philip D. and Upchurch, Paul and Barnes, Rosie N. and Mateus, Octávio",
    title = "Osteology of the Late Jurassic Portuguese sauropod dinosaur Lusotitan atalaiensis (Macronaria) and the evolutionary history of basal titanosauriforms",
    year = "2013",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "Titanosauriforms represent a diverse and globally distributed clade of neosauropod dinosaurs, but their inter-relationships remain poorly understood. Here we redescribe Lusotitan atalaiensis from the Late Jurassic Lourinhã Formation of Portugal, a taxon previously referred to Brachiosaurus. The lectotype includes cervical, dorsal, and caudal vertebrae, and elements from the forelimb, hindlimb, and pelvic girdle. Lusotitan is a valid taxon and can be diagnosed by six autapomorphies, including the presence of elongate postzygapophyses that project well beyond the posterior margin of the neural arch in anterior-to-middle caudal vertebrae. A new phylogenetic analysis, focused on elucidating the evolutionary relationships of basal titanosauriforms, is presented, comprising 63 taxa scored for 279 characters. Many of these characters are heavily revised or novel to our study, and a number of ingroup taxa have never previously been incorporated into a phylogenetic analysis. We treated quantitative characters as discrete and continuous data in two parallel analyses, and explored the effect of implied weighting. Although we recovered monophyletic brachiosaurid and somphospondylan sister clades within Titanosauriformes, their compositions were affected by alternative treatments of quantitative data and, especially, by the weighting of such data. This suggests that the treatment of quantitative data is important and the wrong decisions might lead to incorrect tree topologies. In particular, the diversity of Titanosauria was greatly increased by the use of implied weights. Our results support the generic separation of the contemporaneous taxa Brachiosaurus, Giraffatitan, and Lusotitan, with the latter recovered as either a brachiosaurid or the sister taxon to Titanosauriformes. Although Janenschia was recovered as a basal macronarian, outside Titanosauria, the sympatric Australodocus provides body fossil evidence for the pre-Cretaceous origin of titanosaurs. We recovered evidence for a sauropod with close affinities to the Chinese taxon Mamenchisaurus in the Late Jurassic Tendaguru beds of Africa, and present new information demonstrating the wider distribution of caudal pneumaticity within Titanosauria. The earliest known titanosauriform body fossils are from the late Oxfordian (Late Jurassic), although trackway evidence indicates a Middle Jurassic origin. Diversity increased throughout the Late Jurassic, and titanosauriforms did not undergo a severe extinction across the Jurassic/Cretaceous boundary, in contrast to diplodocids and non-neosauropods. Titanosauriform diversity increased in the Barremian and Aptian–Albian as a result of radiations of derived somphospondylans and lithostrotians, respectively, but there was a severe drop (up to 40\%) in species numbers at, or near, the Albian/Cenomanian boundary, representing a faunal turnover whereby basal titanosauriforms were replaced by derived titanosaurs, although this transition occurred in a spatiotemporally staggered fashion.",
    url = "https://doi.org/10.1111/zoj.12029",
    doi = "10.1111/zoj.12029",
    openalex = "W1572867283",
    references = "doi101002jez513, doi101016jgr201212009, doi101017s0094837300026543, doi101038nature04633, doi101046j10963642200200029x, doi101073pnas1011369108, doi10108002724634199910011178, doi101080027246342012671204, doi101080147720192011630927, doi101093oso97801985052350010001, doi101111j109600311993tb00209x, doi101111j109600312003tb00376x, doi101111j10960031200800217x, doi101111j109636421998tb00569x, doi101111j1469185x200900107x, doi101111j1469185x201100190x, doi101139e93176, doi101144001676492006032, doi10129879781933789439, doi101371journalpone0001230, doi101371journalpone0006190, doi101371journalpone0006924, doi101371journalpone0017114, doi101525california97805202420980010001, doi101525california97805202420980030015, doi101525california97805202462320010001, doi10167102724634200727931dtftco20co2, doi1023071292217, doi1023073889325, doi102475ajss31695411, doi102475ajss319111253, doi104202app20080049, doi104202app20110051, doi105281zenodo16171435, martinsander2006bone, openalexw1025856234, openalexw2294506137, openalexw2611511275, openalexw3114518543, openalexw603337959, openalexw70084438, ostrom2020stratigraphy"
}

ABSTRACT The Early Cretaceous Jehol Biota of northeastern China has become famous over the last two decades as a source of feathered avialan and non-avialan theropods, preserved alongside an array of other fossil vertebrates, invertebrates, and plants. Still more recently, a rich assemblage referred to in this paper as the Daohugou Biota has begun to emerge from Jurassic strata in the same region. Like their counterparts from the Jehol Biota, Daohugou Biota vertebrate specimens are typically preserved in fine-grained lacustrine beds and often retain feathers and other soft-tissue features. At present, 30 vertebrate taxa (five salamanders, one anuran, two lizards, 13 pterosaurs, five dinosaurs, and four mammals) are known from the Daohugou Biota, which was first recognized at the Daohugou locality in Inner Mongolia. The presence of the salamander Chunerpeton tianyiensis, proposed in this paper as an index fossil for the Daohugou Biota, links the Daohugou locality to five other fossil-producing areas in the provinces of Hebei and Liaoning. The strata containing the Daohugou Biota are close to the Middle–Upper Jurassic boundary and belong at least partly to the regionally widespread Tiaojishan Formation. In general, the vertebrate fauna of the Daohugou Biota is strikingly different from that of the Jehol Biota, although paravian dinosaurs, anurognathid pterosaurs, and salamanders with cryptobranchid and hynobiid affinities occur in both. Nevertheless, the Daohugou Biota and the Jehol Biota are two successive Lagerstätte assemblages that collectively offer a taphonomically consistent window into the Mesozoic life of northeast Asia over a significant span of geologic time.

@article{doi101080027246342013787316,
    author = "Sullivan, Corwin and Wang, Yuan and Hone, David W. E. and Wang, Yuan and Xu, Xing and Zhang, Fucheng",
    title = "The vertebrates of the Jurassic Daohugou Biota of northeastern China",
    year = "2014",
    journal = "Journal of Vertebrate Paleontology",
    abstract = "ABSTRACT The Early Cretaceous Jehol Biota of northeastern China has become famous over the last two decades as a source of feathered avialan and non-avialan theropods, preserved alongside an array of other fossil vertebrates, invertebrates, and plants. Still more recently, a rich assemblage referred to in this paper as the Daohugou Biota has begun to emerge from Jurassic strata in the same region. Like their counterparts from the Jehol Biota, Daohugou Biota vertebrate specimens are typically preserved in fine-grained lacustrine beds and often retain feathers and other soft-tissue features. At present, 30 vertebrate taxa (five salamanders, one anuran, two lizards, 13 pterosaurs, five dinosaurs, and four mammals) are known from the Daohugou Biota, which was first recognized at the Daohugou locality in Inner Mongolia. The presence of the salamander Chunerpeton tianyiensis, proposed in this paper as an index fossil for the Daohugou Biota, links the Daohugou locality to five other fossil-producing areas in the provinces of Hebei and Liaoning. The strata containing the Daohugou Biota are close to the Middle–Upper Jurassic boundary and belong at least partly to the regionally widespread Tiaojishan Formation. In general, the vertebrate fauna of the Daohugou Biota is strikingly different from that of the Jehol Biota, although paravian dinosaurs, anurognathid pterosaurs, and salamanders with cryptobranchid and hynobiid affinities occur in both. Nevertheless, the Daohugou Biota and the Jehol Biota are two successive Lagerstätte assemblages that collectively offer a taphonomically consistent window into the Mesozoic life of northeast Asia over a significant span of geologic time.",
    url = "https://doi.org/10.1080/02724634.2013.787316",
    doi = "10.1080/02724634.2013.787316",
    openalex = "W2081152623",
    references = "doi101002gj1045, doi101007s0011400804883, doi101007s1143001040949, doi101038nature12168, doi101073pnas1203238109, doi101144gslsp20032170111, doi101666040141"
}

This article describes the sedimentological characteristics of dinosaur ichnites at three sites within the municipal area of El Castellar (in the Province of Teruel, Aragón, Spain): El Castellar (CT-1), El Pozo (CT-2), and Camino El Berzal (CT-3). These sites possess large concentrations of footprints made by quadrupedal (sauropod, stegosaurid and ornithopod) and bipedal theropod dinosaurs. Among the more than 800 documented footprints at CT-1 is a trail left by a large theropod, and at least one other made by a stegosaurid (the holotype of Deltapodus ibericus). CT-3 contains some of the largest sauropod footprints ever found in the Iberian Peninsula. The three sites lie within the Villar del Arzobispo Formation, which was deposited over the Tithonian-Berriasian period in an environment under tidal influence. Tidal carbonates host the largest number of footprints. Different footprint shapes and degrees of preservation are apparent, even within a single layer, reflecting the characteristics of the original sediment in which the footprints were made. The grain size and water content of the original sediment, primarily the micritic mud derived from the pellets when it contains some water, appear to have been the most important factors in determining the quality of the preserved prints. The presence of algal mats appear to have been less important, because the mats detected inside the massive or pelletoidal micrite were broken and deformed, and would therefore not have invested the substrate with cohesion enough to favor footprint preservation.

@article{doi101080104209402013873721,
    author = "Alcalá, Luís and Pérez‐Lorente, Félix and Luque, Luis and Cobos, Alberto and Royo‐Torres, Rafael and Mampel, Luis",
    title = "Preservation of Dinosaur Footprints in Shallow Intertidal Deposits of the Jurassic-Cretaceous Transition in the Iberian Range (Teruel, Spain)",
    year = "2014",
    journal = "Ichnos/Ichnos : an international journal for plant and animal traces",
    abstract = "This article describes the sedimentological characteristics of dinosaur ichnites at three sites within the municipal area of El Castellar (in the Province of Teruel, Aragón, Spain): El Castellar (CT-1), El Pozo (CT-2), and Camino El Berzal (CT-3). These sites possess large concentrations of footprints made by quadrupedal (sauropod, stegosaurid and ornithopod) and bipedal theropod dinosaurs. Among the more than 800 documented footprints at CT-1 is a trail left by a large theropod, and at least one other made by a stegosaurid (the holotype of Deltapodus ibericus). CT-3 contains some of the largest sauropod footprints ever found in the Iberian Peninsula. The three sites lie within the Villar del Arzobispo Formation, which was deposited over the Tithonian-Berriasian period in an environment under tidal influence. Tidal carbonates host the largest number of footprints. Different footprint shapes and degrees of preservation are apparent, even within a single layer, reflecting the characteristics of the original sediment in which the footprints were made. The grain size and water content of the original sediment, primarily the micritic mud derived from the pellets when it contains some water, appear to have been the most important factors in determining the quality of the preserved prints. The presence of algal mats appear to have been less important, because the mats detected inside the massive or pelletoidal micrite were broken and deformed, and would therefore not have invested the substrate with cohesion enough to favor footprint preservation.",
    url = "https://doi.org/10.1080/10420940.2013.873721",
    doi = "10.1080/10420940.2013.873721",
    openalex = "W2019550968",
    references = "doi101007s1254901200793"
}

Theropod dinosaurs form a highly diversified clade, and their teeth are some of the most common components of the Mesozoic dinosaur fossil record. This is the case in the Lourinhã Formation (Late Jurassic, Kimmeridgian-Tithonian) of Portugal, where theropod teeth are particularly abundant and diverse. Four isolated theropod teeth are here described and identified based on morphometric and anatomical data. They are included in a cladistic analysis performed on a data matrix of 141 dentition-based characters coded in 60 taxa, as well as a supermatrix combining our dataset with six recent datamatrices based on the whole theropod skeleton. The consensus tree resulting from the dentition-based data matrix reveals that theropod teeth provide reliable data for identification at approximately family level. Therefore, phylogenetic methods will help identifying theropod teeth with more confidence in the future. Although dental characters do not reliably indicate relationships among higher clades of theropods, they demonstrate interesting patterns of homoplasy suggesting dietary convergence in (1) alvarezsauroids, therizinosaurs and troodontids; (2) coelophysoids and spinosaurids; (3) compsognathids and dromaeosaurids; and (4) ceratosaurids, allosauroids and megalosaurids. Based on morphometric and cladistic analyses, the biggest tooth from Lourinhã is referred to a mesial crown of the megalosaurid Torvosaurus tanneri, due to the elliptical cross section of the crown base, the large size and elongation of the crown, medially positioned mesial and distal carinae, and the coarse denticles. The smallest tooth is identified as Richardoestesia, and as a close relative of R. gilmorei based on the weak constriction between crown and root, the "eight-shaped" outline of the base crown and, on the distal carina, the average of ten symmetrically rounded denticles per mm, as well as a subequal number of denticles basally and at mid-crown. Finally, the two medium-sized teeth belong to the same taxon and exhibit pronounced interdenticular sulci between distal denticles, hooked distal denticles for one of them, an irregular enamel texture, and a straight distal margin, a combination of features only observed in abelisaurids. They provide the first record of Abelisauridae in the Jurassic of Laurasia and one of the oldest records of this clade in the world, suggesting a possible radiation of Abelisauridae in Europe well before the Upper Cretaceous.

@article{doi1011646zootaxa375911,
    author = "Hendrickx, Christophe and Mateus, Octávio",
    title = "Abelisauridae (Dinosauria: Theropoda) from the Late Jurassic of Portugal and dentition-based phylogeny as a contribution for the identification of isolated theropod teeth",
    year = "2014",
    journal = "Zootaxa",
    abstract = {Theropod dinosaurs form a highly diversified clade, and their teeth are some of the most common components of the Mesozoic dinosaur fossil record. This is the case in the Lourinhã Formation (Late Jurassic, Kimmeridgian-Tithonian) of Portugal, where theropod teeth are particularly abundant and diverse. Four isolated theropod teeth are here described and identified based on morphometric and anatomical data. They are included in a cladistic analysis performed on a data matrix of 141 dentition-based characters coded in 60 taxa, as well as a supermatrix combining our dataset with six recent datamatrices based on the whole theropod skeleton. The consensus tree resulting from the dentition-based data matrix reveals that theropod teeth provide reliable data for identification at approximately family level. Therefore, phylogenetic methods will help identifying theropod teeth with more confidence in the future. Although dental characters do not reliably indicate relationships among higher clades of theropods, they demonstrate interesting patterns of homoplasy suggesting dietary convergence in (1) alvarezsauroids, therizinosaurs and troodontids; (2) coelophysoids and spinosaurids; (3) compsognathids and dromaeosaurids; and (4) ceratosaurids, allosauroids and megalosaurids. Based on morphometric and cladistic analyses, the biggest tooth from Lourinhã is referred to a mesial crown of the megalosaurid Torvosaurus tanneri, due to the elliptical cross section of the crown base, the large size and elongation of the crown, medially positioned mesial and distal carinae, and the coarse denticles. The smallest tooth is identified as Richardoestesia, and as a close relative of R. gilmorei based on the weak constriction between crown and root, the "eight-shaped" outline of the base crown and, on the distal carina, the average of ten symmetrically rounded denticles per mm, as well as a subequal number of denticles basally and at mid-crown. Finally, the two medium-sized teeth belong to the same taxon and exhibit pronounced interdenticular sulci between distal denticles, hooked distal denticles for one of them, an irregular enamel texture, and a straight distal margin, a combination of features only observed in abelisaurids. They provide the first record of Abelisauridae in the Jurassic of Laurasia and one of the oldest records of this clade in the world, suggesting a possible radiation of Abelisauridae in Europe well before the Upper Cretaceous.},
    url = "https://doi.org/10.11646/zootaxa.3759.1.1",
    doi = "10.11646/zootaxa.3759.1.1",
    openalex = "W2141232902",
    references = "benson2008a, carpenter2005the, crossref1976allosaurus, doi101002ara20206, doi101002jmor10372, doi101007bf02987808, doi101017s0016756804000330, doi101038324359a0, doi10103832884, doi10103835047056, doi101073pnas1011924108, doi101080027246342013820113, doi101098rspb20110410, doi101098rspb20120660, doi101098rspl18870117, doi101111j109600311994tb00179x, doi101111j10960031200800217x, doi101111j109636421978tb01049x, doi1011270077774920100125, doi101139e10005, doi10120600030082200635451andtfu20co2, doi1012063521, doi1012066481, doi101371journalpone0017932, doi101371journalpone0054329, doi1016660022336020010750208lcsdaf20co2, doi1016660022336020020760751stabtf20co2, doi101671027246342003231apfast20co2, doi1016710272463420050250865hitrif20co2, doi1016710272463420072787antdtf20co2, doi102475ajss319111253, doi1034191b109, doi104202app20120121, doi105281zenodo1048848, doi105281zenodo16171435, mateus2010a, openalexw1821824396, openalexw1879660213, openalexw2764433274, openalexw3215057009, openalexw834136096, rauhut2003a, sues1978a, zhao1998the"
}

The Isle of Skye, Scotland, has yielded a diverse Middle Jurassic terrestrial vertebrate fauna, but little is known about the predatory dinosaurs (theropods) occupying the top and secondary carnivore roles in these ecosystems, as their fossils have been limited to rare footprints of small- to mid-sized taxa. We describe two isolated theropod body fossils, a tooth and a middle-posterior caudal vertebra, from the late Bajocian–Bathonian Valtos Sandstone Formation of northeastern Skye, and use a variety of quantitative techniques to determine their taxonomic affinities. We conservatively refer both specimens to Theropoda indet., but suggest that the tooth most likely belonged to a megalosaurid, basal tyrannosauroid, or dromaeosaurid, and that the vertebra belonged to a small-bodied basal coelurosaur of approximately the same size as Coelurus (c. 2 m long, c. 30 kg mass). Although fragmentary, these fossils and the footprints demonstrate that both small and mid to large theropods were present in the Middle Jurassic of Scotland, and that these may have included some of the oldest coelurosaurs, and potentially some of the earliest-diverging tyrannosauroids and dromaeosaurids. Supplementary material Skye Theropod Tooth: Data and Analyses are available at www.geolsoc.org.uk/SUP18866

@article{doi101144sjg2014022,
    author = "Brusatte, Stephen L. and Clark, Neil D. L.",
    title = "Theropod dinosaurs from the Middle Jurassic (Bajocian–Bathonian) of Skye, Scotland",
    year = "2015",
    journal = "Scottish Journal of Geology",
    abstract = "The Isle of Skye, Scotland, has yielded a diverse Middle Jurassic terrestrial vertebrate fauna, but little is known about the predatory dinosaurs (theropods) occupying the top and secondary carnivore roles in these ecosystems, as their fossils have been limited to rare footprints of small- to mid-sized taxa. We describe two isolated theropod body fossils, a tooth and a middle-posterior caudal vertebra, from the late Bajocian–Bathonian Valtos Sandstone Formation of northeastern Skye, and use a variety of quantitative techniques to determine their taxonomic affinities. We conservatively refer both specimens to Theropoda indet., but suggest that the tooth most likely belonged to a megalosaurid, basal tyrannosauroid, or dromaeosaurid, and that the vertebra belonged to a small-bodied basal coelurosaur of approximately the same size as Coelurus (c. 2 m long, c. 30 kg mass). Although fragmentary, these fossils and the footprints demonstrate that both small and mid to large theropods were present in the Middle Jurassic of Scotland, and that these may have included some of the oldest coelurosaurs, and potentially some of the earliest-diverging tyrannosauroids and dromaeosaurids. Supplementary material Skye Theropod Tooth: Data and Analyses are available at www.geolsoc.org.uk/SUP18866",
    url = "https://doi.org/10.1144/sjg2014-022",
    doi = "10.1144/sjg2014-022",
    openalex = "W2264230805",
    references = "doi101007s1254901200793"
}

Upper Triassic and Middle Jurassic strata of the Xichang Basin in Sichuan Province, southwestern China, yielded important dinosaur ichnofossils. From the Xujiahe Formation of the Yiguojiao tracksite, we report a Late Triassic footprint assemblage in China and the first discovery of diagnostic Triassic sauropodomorph tracks in this region. The tracks share a number of features in common with the ichnogenera Eosauropus (Late Triassic) and Liujianpus (Early Jurassic). The neighboring Bingtu tracksite is stratigraphically younger (Shaximiao Formation, Middle Jurassic) and preserves small tridactyl theropod tracks that represent the first occurrence of the ichnotaxon Carmelopodus in China and Asia. While these tracks are morphologically comparable to those from the Middle Jurassic type locality in North America, the specimens from China show the proximal margin of the digit IV impression in a more cranial position, which may indicate a trackmaker with a relatively short metatarsal IV. In addition to the skeletal record, the Carmelopodus footprints document the presence of small theropods in the dinosaur fauna of the Middle Jurassic Shaximiao Formation.

@article{doi101016jjop201711004,
    author = "Xing, Lida and Ba, Jin and Lockley, Martin G. and Klein, Hendrik and Yan, Sheng-Wu and Romilio, Anthony and Chou, Chunyong and Persons, W. Scott",
    title = "Late Triassic sauropodomorph and Middle Jurassic theropod tracks from the Xichang Basin, Sichuan Province, southwestern China: First report of the ichnogenus Carmelopodus",
    year = "2017",
    journal = "Journal of Palaeogeography",
    abstract = "Upper Triassic and Middle Jurassic strata of the Xichang Basin in Sichuan Province, southwestern China, yielded important dinosaur ichnofossils. From the Xujiahe Formation of the Yiguojiao tracksite, we report a Late Triassic footprint assemblage in China and the first discovery of diagnostic Triassic sauropodomorph tracks in this region. The tracks share a number of features in common with the ichnogenera Eosauropus (Late Triassic) and Liujianpus (Early Jurassic). The neighboring Bingtu tracksite is stratigraphically younger (Shaximiao Formation, Middle Jurassic) and preserves small tridactyl theropod tracks that represent the first occurrence of the ichnotaxon Carmelopodus in China and Asia. While these tracks are morphologically comparable to those from the Middle Jurassic type locality in North America, the specimens from China show the proximal margin of the digit IV impression in a more cranial position, which may indicate a trackmaker with a relatively short metatarsal IV. In addition to the skeletal record, the Carmelopodus footprints document the presence of small theropods in the dinosaur fauna of the Middle Jurassic Shaximiao Formation.",
    url = "https://doi.org/10.1016/j.jop.2017.11.004",
    doi = "10.1016/j.jop.2017.11.004",
    openalex = "W2768452499",
    references = "doi101016jcretres200510009, doi101038261129a0, doi10108010420940390257914, doi10108010420940490442296, doi1011111755672412026, doi104202app003742017, doi105962bhltitle70405, doi10718895fylantbak30809522, lull1915triassic, openalexw2149387945, openalexw2619609965, openalexw3147398959"
}

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"
}

A new ichnospecies of a large theropod dinosaur, Megalosauripus transjuranicus, is described from the Reuchenette Formation (Early-Late Kimmeridgian, Late Jurassic) of NW Switzerland. It is based on very well-preserved and morphologically-distinct tracks (impressions) and several trackways, including different preservational types from different tracksites and horizons. All trackways were excavated along federal Highway A16 near Courtedoux (Canton Jura) and systematically documented in the field including orthophotos and laserscans. The best-preserved tracks were recovered and additional tracks were casted. Megalosauripus transjuranicus is characterized by tridactyl tracks with clear claw and digital pad impressions, and notably an exceptionally large and round first phalangeal pad on the fourth digit (PIV1) that is connected to digit IV and forms the round heel area. Due to this combination of features, M. transjuranicus clearly is of theropod (and not ornithopod) origin. M. transjuranicus is compared to other Megalosauripus tracks and similar ichnotaxa and other unassigned tracks from the Early Jurassic to Early Cretaceous. It is clearly different from other ichnogenera assigned to large theropods such as Eubrontes-Grallator from the Late Triassic and Early Jurassic or Megalosauripus-Megalosauropus-Bueckeburgichnus and Therangospodus tracks from the Late Jurassic and Early Cretaceous. A second tridactyl morphotype (called Morphotype II) is different from Megalosauripus transjuranicus in being subsymmetric, longer than wide (sometimes almost as wide as long), with blunt toe impressions and no evidence for discrete phalangeal pad and claw marks. Some Morphotype II tracks are found in trackways that are assigned to M. transjuranicus, to M.? transjuranicus or M. cf. transjuranicus indicating that some Morphotype II tracks are intra-trackway preservational variants of a morphological continuum of Megalosauripus transjuranicus. On the other hand, several up to 40 steps long trackways very consistently present Morphotype II features (notably blunt digits) and do not exhibit any of the features that are typical for Megalosauripus (notably phalangeal pads). Therefore, it is not very likely that these tracks are preservational variants of Megalosauripus transjuranicus or Megalosauripus isp. These trackways are interpreted to have been left by an ornithopod dinosaur. The high frequency of large theropod tracks in tidal-flat deposits of the Jura carbonate platform, associated on single ichnoassemblages with minute to medium-sized tridactyl and tiny to large sauropod tracks has important implications for the dinosaur community and for paleoenvironmental and paleogeographical reconstructions. As with most other known occurrences of Megalosauripus tracks, M. transjuranicus is found in coastal settings, which may reflect the preference of their theropod trackmakers for expanded carbonate flats where food was abundant.

@article{doi101371journalpone0180289,
    author = "Razzolini, Novella L. and Belvedere, Matteo and Marty, Daniel and Paratte, Géraldine and Lovis, Christel and Cattin, Marielle and Meyer, Christian A.",
    title = "Megalosauripus transjuranicus ichnosp. nov. A new Late Jurassic theropod ichnotaxon from NW Switzerland and implications for tridactyl dinosaur ichnology and ichnotaxomy",
    year = "2017",
    journal = "PLoS ONE",
    abstract = "A new ichnospecies of a large theropod dinosaur, Megalosauripus transjuranicus, is described from the Reuchenette Formation (Early-Late Kimmeridgian, Late Jurassic) of NW Switzerland. It is based on very well-preserved and morphologically-distinct tracks (impressions) and several trackways, including different preservational types from different tracksites and horizons. All trackways were excavated along federal Highway A16 near Courtedoux (Canton Jura) and systematically documented in the field including orthophotos and laserscans. The best-preserved tracks were recovered and additional tracks were casted. Megalosauripus transjuranicus is characterized by tridactyl tracks with clear claw and digital pad impressions, and notably an exceptionally large and round first phalangeal pad on the fourth digit (PIV1) that is connected to digit IV and forms the round heel area. Due to this combination of features, M. transjuranicus clearly is of theropod (and not ornithopod) origin. M. transjuranicus is compared to other Megalosauripus tracks and similar ichnotaxa and other unassigned tracks from the Early Jurassic to Early Cretaceous. It is clearly different from other ichnogenera assigned to large theropods such as Eubrontes-Grallator from the Late Triassic and Early Jurassic or Megalosauripus-Megalosauropus-Bueckeburgichnus and Therangospodus tracks from the Late Jurassic and Early Cretaceous. A second tridactyl morphotype (called Morphotype II) is different from Megalosauripus transjuranicus in being subsymmetric, longer than wide (sometimes almost as wide as long), with blunt toe impressions and no evidence for discrete phalangeal pad and claw marks. Some Morphotype II tracks are found in trackways that are assigned to M. transjuranicus, to M.? transjuranicus or M. cf. transjuranicus indicating that some Morphotype II tracks are intra-trackway preservational variants of a morphological continuum of Megalosauripus transjuranicus. On the other hand, several up to 40 steps long trackways very consistently present Morphotype II features (notably blunt digits) and do not exhibit any of the features that are typical for Megalosauripus (notably phalangeal pads). Therefore, it is not very likely that these tracks are preservational variants of Megalosauripus transjuranicus or Megalosauripus isp. These trackways are interpreted to have been left by an ornithopod dinosaur. The high frequency of large theropod tracks in tidal-flat deposits of the Jura carbonate platform, associated on single ichnoassemblages with minute to medium-sized tridactyl and tiny to large sauropod tracks has important implications for the dinosaur community and for paleoenvironmental and paleogeographical reconstructions. As with most other known occurrences of Megalosauripus tracks, M. transjuranicus is found in coastal settings, which may reflect the preference of their theropod trackmakers for expanded carbonate flats where food was abundant.",
    url = "https://doi.org/10.1371/journal.pone.0180289",
    doi = "10.1371/journal.pone.0180289",
    openalex = "W2735513027",
    references = "crossref1976allosaurus, doi1010079789400904095, doi101016s0012821x0100588x, doi101016s001669958880038x, doi101017cbo9780511628948, doi101038261129a0, doi101038srep31494, doi10108000241160600787890, doi10108008912960903503345, doi101080147720192011630927, doi101306m43478, doi101371journalpone0103613, doi1026879529, doi105860choice273305, doi107717peerj2059, fiorillo2014herd, mateus2010a, nouri2011tetradactyl"
}

@article{doi101007s4151301900106y,
    author = "Campos‐Soto, Sonia and Benito, M. Isabel and Cobos, Alberto and Caus, Esmeralda and Quijada, Isabel Emma and Suárez-González, Pablo and Mayoral, José Ramón Mas and Royo‐Torres, Rafael and Alcalá, Luís",
    title = "Revisiting the age and palaeoenvironments of the Upper Jurassic–Lower Cretaceous? dinosaur-bearing sedimentary record of eastern Spain: implications for Iberian palaeogeography",
    year = "2019",
    journal = "Journal of Iberian Geology",
    url = "https://doi.org/10.1007/s41513-019-00106-y",
    doi = "10.1007/s41513-019-00106-y",
    openalex = "W2943476570",
    references = "doi101007s1254901200793, doi101016s0016699588800913"
}

The Middle Jurassic is a largely mysterious interval in dinosaur evolution, as few fossils of this age are known worldwide. In recent years, the Isle of Skye has yielded a substantial record of trackways, and a more limited inventory of body fossils, that indicate a diverse fauna of Middle Jurassic dinosaurs living in and around lagoons and deltas. Comparatively little is known about the predators in these faunas (particularly theropod dinosaurs), as their fossils are among the rarest discoveries. We here report two new isolated theropod teeth, from the Valtos Sandstone Formation and Lealt Shale Formation of Skye, which we visualized and measured using high-resolution x-ray computed microtomographic scanning (µCT) and identified via statistical and phylogenetic analyses of a large comparative dental dataset. We argue that these teeth most likely represent at least two theropod species – one small-bodied and the other large-bodied – which likely belonged to one or several clades of basal avetheropods (ceratosaurs, megalosauroids, or allosauroids). These groups, which were diversifying during the Middle Jurassic and would become dominant in the Late Jurassic, filled various niches in the food chain of Skye, probably both on land and in the lagoons. Supplementary material: Character lists, datasets, and measurements are available at https://doi.org/10.6084/m9.figshare.c.4452533

@article{doi101144sjg2018020,
    author = "Young, Chloe M.E. and Hendrickx, Christophe and Challands, Thomas J. and Foffa, Davide and Ross, Dugald A. and Butler, Ian B. and Brusatte, Stephen L.",
    title = "New theropod dinosaur teeth from the Middle Jurassic of the Isle of Skye, Scotland",
    year = "2019",
    journal = "Scottish Journal of Geology",
    abstract = "The Middle Jurassic is a largely mysterious interval in dinosaur evolution, as few fossils of this age are known worldwide. In recent years, the Isle of Skye has yielded a substantial record of trackways, and a more limited inventory of body fossils, that indicate a diverse fauna of Middle Jurassic dinosaurs living in and around lagoons and deltas. Comparatively little is known about the predators in these faunas (particularly theropod dinosaurs), as their fossils are among the rarest discoveries. We here report two new isolated theropod teeth, from the Valtos Sandstone Formation and Lealt Shale Formation of Skye, which we visualized and measured using high-resolution x-ray computed microtomographic scanning (µCT) and identified via statistical and phylogenetic analyses of a large comparative dental dataset. We argue that these teeth most likely represent at least two theropod species – one small-bodied and the other large-bodied – which likely belonged to one or several clades of basal avetheropods (ceratosaurs, megalosauroids, or allosauroids). These groups, which were diversifying during the Middle Jurassic and would become dominant in the Late Jurassic, filled various niches in the food chain of Skye, probably both on land and in the lagoons. Supplementary material: Character lists, datasets, and measurements are available at https://doi.org/10.6084/m9.figshare.c.4452533",
    url = "https://doi.org/10.1144/sjg2018-020",
    doi = "10.1144/sjg2018-020",
    openalex = "W2927160134",
    references = "doi101080147720192013781067, doi101111zoj12425, doi101371journalpone0158334, doi104202app000562013"
}

The Upper Jurassic Morrison Formation of the western United States preserves one of the best-known Mesozoic paleoecosystems worldwide. The formation crops out over an area from New Mexico and Oklahoma to Montana and Utah and encompasses a time span of approximately eight million years. Recent studies indicate a high diversity of gigantic, herbivorous sauropod dinosaurs, but the geographic and temporal distributions of species or even genera of these animals remain poorly understood. In particular, sauropod specimens from northern outcrops of the formation have rarely been studied in detail, and temporal relationships among sites are imprecise. Here, we reassess the taxonomic diversity of the sauropods from a historic Carnegie Museum locality in northern Wyoming. Previous referrals of material to the well-known diplodocid genera Apatosaurus and Diplodocus cannot be confidently confirmed; instead, all these specimens more likely represent elements from the recently recognized Galeamopus. Specimens previously assigned to Camarasaurus and Haplocanthosaurus could not be referred to these genera based on apomorphies, due to a lack of detailed knowledge concerning the genus- and species-level taxonomy of these sauropods. Our findings imply that many referrals of incomplete diplodocid skeletons to Apatosaurus and Diplodocus must be reassessed. These reassessments are particularly important with regard to specimens from northern localities of the Morrison Formation, as it is becoming increasingly evident that diplodocids from this area were distinct from better-known, more southerly taxa. This geographic segregation does not seem to apply to nondiplodocid sauropods; however, these taxa are also in need of systematic revision, which may reveal species-level patterns similar to those observed in Diplodocidae.

@article{doi1012060003009043711,
    author = "Tschopp, Emanuel and Maidment, Susannah C. R. and Lamanna, Matthew C. and Norell, Mark A.",
    title = "Reassessment of a Historical Collection of Sauropod Dinosaurs from the Northern Morrison Formation of Wyoming, with Implications for Sauropod Biogeography",
    year = "2019",
    journal = "Bulletin of the American Museum of Natural History",
    abstract = "The Upper Jurassic Morrison Formation of the western United States preserves one of the best-known Mesozoic paleoecosystems worldwide. The formation crops out over an area from New Mexico and Oklahoma to Montana and Utah and encompasses a time span of approximately eight million years. Recent studies indicate a high diversity of gigantic, herbivorous sauropod dinosaurs, but the geographic and temporal distributions of species or even genera of these animals remain poorly understood. In particular, sauropod specimens from northern outcrops of the formation have rarely been studied in detail, and temporal relationships among sites are imprecise. Here, we reassess the taxonomic diversity of the sauropods from a historic Carnegie Museum locality in northern Wyoming. Previous referrals of material to the well-known diplodocid genera Apatosaurus and Diplodocus cannot be confidently confirmed; instead, all these specimens more likely represent elements from the recently recognized Galeamopus. Specimens previously assigned to Camarasaurus and Haplocanthosaurus could not be referred to these genera based on apomorphies, due to a lack of detailed knowledge concerning the genus- and species-level taxonomy of these sauropods. Our findings imply that many referrals of incomplete diplodocid skeletons to Apatosaurus and Diplodocus must be reassessed. These reassessments are particularly important with regard to specimens from northern localities of the Morrison Formation, as it is becoming increasingly evident that diplodocids from this area were distinct from better-known, more southerly taxa. This geographic segregation does not seem to apply to nondiplodocid sauropods; however, these taxa are also in need of systematic revision, which may reveal species-level patterns similar to those observed in Diplodocidae.",
    url = "https://doi.org/10.1206/0003-0090.437.1.1",
    doi = "10.1206/0003-0090.437.1.1",
    openalex = "W2985499099",
    references = "brinkman2010the, doi105962bhltitle102117"
}

Abstract Dinosaur remains were discovered in the 1860’s in the Kimmeridgian (Late Jurassic) Reuchenette Formation of Moutier, northwestern Switzerland. In the 1920’s, these were identified as a new species of sauropod, Ornithopsis greppini, before being reclassified as a species of Cetiosauriscus (C. greppini), otherwise known from the type species (C. stewarti) from the late Middle Jurassic (Callovian) of the UK. The syntype of “ C. greppini ” consists of skeletal elements from all body regions, and at least four individuals of different sizes can be distinguished. Here we fully re-describe this material, and re-evaluate its taxonomy and systematic placement. The Moutier locality also yielded a theropod tooth, and fragmentary cranial and vertebral remains of a crocodylomorph, also re-described here. “ C.” greppini is a small-sized (not more than 10 m long) non-neosauropod eusauropod. Cetiosauriscus stewarti and “ C.” greppini differ from each other in: (1) size; (2) the neural spine morphology and diapophyseal laminae of the anterior caudal vertebrae; (3) the length-to-height proportion in the middle caudal vertebrae; (4) the presence or absence of ridges and crests on the middle caudal centra; and (5) the shape and proportions of the coracoid, humerus, and femur. These anatomical differences, combined with their discrepancy in stratigraphic age, make it unlikely that C. stewarti and “ C.” greppini belong to the same genus, as also supported through our phylogenetic analysis. “ C.” greppini cannot be assigned to any other contemporaneous sauropod taxon from Europe, but is diagnosed by an autapomorphic rugosity on the posteromedial margin of the humerus, as well as a unique combination of features. As such, we erect the new genus name Amanzia for the Swiss taxon “ Ornithopsis ” greppini, augmenting the growing diversity of Late Jurassic European sauropods. Our phylogenetic analysis places it outside of Neosauropoda, either as the sister taxon to that clade, or as a member of Turiasauria. ZooBank LSID: urn:lsid:zoobank.org:pub:37860D8F-E49C-4F6B-9F51-705153499C1A.

@article{doi101186s00015020003555,
    author = "Schwarz, Daniela and Mannion, Philip D. and Wings, Oliver and Meyer, Christian A.",
    title = "Re-description of the sauropod dinosaur Amanzia (“Ornithopsis/Cetiosauriscus”) greppini n. gen. and other vertebrate remains from the Kimmeridgian (Late Jurassic) Reuchenette Formation of Moutier, Switzerland",
    year = "2020",
    journal = "Swiss Journal of Geosciences",
    abstract = "Abstract Dinosaur remains were discovered in the 1860’s in the Kimmeridgian (Late Jurassic) Reuchenette Formation of Moutier, northwestern Switzerland. In the 1920’s, these were identified as a new species of sauropod, Ornithopsis greppini, before being reclassified as a species of Cetiosauriscus (C. greppini), otherwise known from the type species (C. stewarti) from the late Middle Jurassic (Callovian) of the UK. The syntype of “ C. greppini ” consists of skeletal elements from all body regions, and at least four individuals of different sizes can be distinguished. Here we fully re-describe this material, and re-evaluate its taxonomy and systematic placement. The Moutier locality also yielded a theropod tooth, and fragmentary cranial and vertebral remains of a crocodylomorph, also re-described here. “ C.” greppini is a small-sized (not more than 10 m long) non-neosauropod eusauropod. Cetiosauriscus stewarti and “ C.” greppini differ from each other in: (1) size; (2) the neural spine morphology and diapophyseal laminae of the anterior caudal vertebrae; (3) the length-to-height proportion in the middle caudal vertebrae; (4) the presence or absence of ridges and crests on the middle caudal centra; and (5) the shape and proportions of the coracoid, humerus, and femur. These anatomical differences, combined with their discrepancy in stratigraphic age, make it unlikely that C. stewarti and “ C.” greppini belong to the same genus, as also supported through our phylogenetic analysis. “ C.” greppini cannot be assigned to any other contemporaneous sauropod taxon from Europe, but is diagnosed by an autapomorphic rugosity on the posteromedial margin of the humerus, as well as a unique combination of features. As such, we erect the new genus name Amanzia for the Swiss taxon “ Ornithopsis ” greppini, augmenting the growing diversity of Late Jurassic European sauropods. Our phylogenetic analysis places it outside of Neosauropoda, either as the sister taxon to that clade, or as a member of Turiasauria. ZooBank LSID: urn:lsid:zoobank.org:pub:37860D8F-E49C-4F6B-9F51-705153499C1A.",
    url = "https://doi.org/10.1186/s00015-020-00355-5",
    doi = "10.1186/s00015-020-00355-5",
    openalex = "W3028708868",
    references = "meyer1998the"
}

Abstract Ankylopollexia was an abundant and diverse clade of ornithopods present in North America, Europe, Africa, and Asia from the Late Jurassic to the Late Cretaceous. However, the relationships between the basal ankylopollexians are poorly understood. A new ankylopollexian ornithopod genus and species is described here, based on a dentary tooth, an ungual pollex of the manus, and an almost complete left hindlimb. The fossils come from deposits of the Villar del Arzobispo Formation (upper Kimmeridgian–Tithonian). Phylogenetic analysis revealed that Oblitosaurus bunnueli gen. et sp. nov. is the basalmost member of Ankylopollexia, together with Draconyx loureiroi. Furthermore, these results have relevant taxonomic implications for the genus Camptosaurus, being the first phylogenetic analysis to support the monophyly of Camptosaurus species. The estimated size of Oblitosaurus bunnueli suggests that it is the largest ornithopod described in the Upper Jurassic of Europe and one of the largest around the world, and could be the trackmaker of large ornithopod tracks found in the Upper Jurassic of the Iberian Peninsula. This discovery increases the known ankylopollexian diversity in Iberia, revealing the presence of an Iberian basal ankylopollexian clade that does not appear to be present in the contemporaneous outcrops of North America.

@article{doi101093zoolinneanzlad076,
    author = "Sánchez-Fenollosa, Sergio and Verdú, Francisco J. and Cobos, Alberto",
    title = "The largest ornithopod (Dinosauria: Ornithischia) from the Upper Jurassic of Europe sheds light on the evolutionary history of basal ankylopollexians",
    year = "2023",
    journal = "Zoological Journal of the Linnean Society",
    abstract = "Abstract Ankylopollexia was an abundant and diverse clade of ornithopods present in North America, Europe, Africa, and Asia from the Late Jurassic to the Late Cretaceous. However, the relationships between the basal ankylopollexians are poorly understood. A new ankylopollexian ornithopod genus and species is described here, based on a dentary tooth, an ungual pollex of the manus, and an almost complete left hindlimb. The fossils come from deposits of the Villar del Arzobispo Formation (upper Kimmeridgian–Tithonian). Phylogenetic analysis revealed that Oblitosaurus bunnueli gen. et sp. nov. is the basalmost member of Ankylopollexia, together with Draconyx loureiroi. Furthermore, these results have relevant taxonomic implications for the genus Camptosaurus, being the first phylogenetic analysis to support the monophyly of Camptosaurus species. The estimated size of Oblitosaurus bunnueli suggests that it is the largest ornithopod described in the Upper Jurassic of Europe and one of the largest around the world, and could be the trackmaker of large ornithopod tracks found in the Upper Jurassic of the Iberian Peninsula. This discovery increases the known ankylopollexian diversity in Iberia, revealing the presence of an Iberian basal ankylopollexian clade that does not appear to be present in the contemporaneous outcrops of North America.",
    url = "https://doi.org/10.1093/zoolinnean/zlad076",
    doi = "10.1093/zoolinnean/zlad076",
    openalex = "W4384666828",
    references = "doi101007s1254901200793"
}

Dinosaur eggshell fragments, from the Upper Jurassic Brushy Basin Member of the Morrison Formation, Utah, were examined using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive Spectroscopy, and Raman Spectroscopy. Analyses revealed that the mammillary tips on the shell interior contain carbonaceous residue. Comparison under the FESEM of these shells with modern bird shells, including some samples heated to diagenetic temperatures, indicate that the residue is degraded organic compounds (DOC). Bird egg membrane is composed of interlaced collagen fibers. Features observed on, and common to, modern bird and dinosaur egg fragments include: (1) irregular-shaped calcium carbonate grains “floating” in an organic matrix; (2) three-dimensional organic fiber matrix; (3) external calcium carbonate molds of fibers in the mammillary bodies; and in heated specimens, (4) carbonaceous residue with ovate to circular pores. However, unlike birds' eggs, the dinosaur eggs contain a calcium carbonate tube around fibrous organic material that emerges from the tube and spreads laterally in a ‘puddle-like' deposit. The sizes of circular organic matrix pores of the dinosaur egg fragments are significantly smaller than those in the bird shells. Gallus gallus domesticus eggshell membranes heated to diagenetic temperatures resulted in alteration of collagen fibers to gel-like substances. The organic matrix with ovate to circular pore openings and the puddle-like deposits in the dinosaur egg fragments are interpreted as the product of membrane thermal diagenesis. The recognition of carbonaceous residue of the shell membrane on dinosaur shell fragments opens newfound opportunities to explore DOC associated with fragmental dinosaur eggs.

@article{lazer2023preserved,
    author = "LAZER, KAYLA and STOUT, IAN P. and SIMPSON, EDWARD L. and WIZEVICH, MICHAEL C. and KEEBLER, ABIGAL M. and HETRICK, GRACE K.",
    title = "PRESERVED MEMBRANE ON DINOSAUR EGGSHELL FRAGMENTS, UPPER JURASSIC MORRISON FORMATION, EASTERN UTAH",
    year = "2023",
    journal = "PALAIOS",
    abstract = "Dinosaur eggshell fragments, from the Upper Jurassic Brushy Basin Member of the Morrison Formation, Utah, were examined using Field Emission Scanning Electron Microscope (FESEM), Energy Dispersive Spectroscopy, and Raman Spectroscopy. Analyses revealed that the mammillary tips on the shell interior contain carbonaceous residue. Comparison under the FESEM of these shells with modern bird shells, including some samples heated to diagenetic temperatures, indicate that the residue is degraded organic compounds (DOC). Bird egg membrane is composed of interlaced collagen fibers. Features observed on, and common to, modern bird and dinosaur egg fragments include: (1) irregular-shaped calcium carbonate grains “floating” in an organic matrix; (2) three-dimensional organic fiber matrix; (3) external calcium carbonate molds of fibers in the mammillary bodies; and in heated specimens, (4) carbonaceous residue with ovate to circular pores. However, unlike birds' eggs, the dinosaur eggs contain a calcium carbonate tube around fibrous organic material that emerges from the tube and spreads laterally in a ‘puddle-like' deposit. The sizes of circular organic matrix pores of the dinosaur egg fragments are significantly smaller than those in the bird shells. Gallus gallus domesticus eggshell membranes heated to diagenetic temperatures resulted in alteration of collagen fibers to gel-like substances. The organic matrix with ovate to circular pore openings and the puddle-like deposits in the dinosaur egg fragments are interpreted as the product of membrane thermal diagenesis. The recognition of carbonaceous residue of the shell membrane on dinosaur shell fragments opens newfound opportunities to explore DOC associated with fragmental dinosaur eggs.",
    url = "https://doi.org/10.2110/palo.2022.002",
    doi = "10.2110/palo.2022.002",
    number = "1",
    openalex = "W4318309511",
    pages = "43-55",
    volume = "38",
    references = "doi1010160022283679905072, doi101016jbpj201104033, doi101016jcoal201604008, doi101016jearscirev2019102936, doi101016jijbiomac200507004, doi10103833573, doi101038ncomms14220, doi101038s4158602024128, doi101111ggr12178, doi101111j13653121201000956x"
}

Gondwanan dinosaur faunae during the 20 Myr preceding the Cretaceous-Palaeogene (K/Pg) extinction included several lineages that were absent or poorly represented in Laurasian landmasses. Among these, the South American fossil record contains diverse abelisaurids, arguably the most successful groups of carnivorous dinosaurs from Gondwana in the Cretaceous, reaching their highest diversity towards the end of this period. Here we describe Koleken inakayali gen. et sp. n., a new abelisaurid from the La Colonia Formation (Maastrichtian, Upper Cretaceous) of Patagonia. Koleken inakayali is known from several skull bones, an almost complete dorsal series, complete sacrum, several caudal vertebrae, pelvic girdle and almost complete hind limbs. The new abelisaurid shows a unique set of features in the skull and several anatomical differences from Carnotaurus sastrei (the only other abelisaurid known from the La Colonia Formation). Koleken inakayali is retrieved as a brachyrostran abelisaurid, clustered with other South American abelisaurids from the latest Cretaceous (Campanian-Maastrichtian), such as Aucasaurus, Niebla and Carnotaurus. Leveraging our phylogeny estimates, we explore rates of morphological evolution across ceratosaurian lineages, finding them to be particularly high for elaphrosaurine noasaurids and around the base of Abelisauridae, before the Early Cretaceous radiation of the latter clade. The Noasauridae and their sister clade show contrasting patterns of morphological evolution, with noasaurids undergoing an early phase of accelerated evolution of the axial and hind limb skeleton in the Jurassic, and the abelisaurids exhibiting sustained high rates of cranial evolution during the Early Cretaceous. These results provide much needed context for the evolutionary dynamics of ceratosaurian theropods, contributing to broader understanding of macroevolutionary patterns across dinosaurs.

@article{doi101111cla12583,
    author = "Pol, Diego and Baiano, Mattia A. and Černý, David and Novas, Fernando E. and Cerda, Ignacio A. and Pittman, Michael",
    title = "A new abelisaurid dinosaur from the end Cretaceous of Patagonia and evolutionary rates among the Ceratosauria",
    year = "2024",
    journal = "Cladistics",
    abstract = "Gondwanan dinosaur faunae during the 20 Myr preceding the Cretaceous-Palaeogene (K/Pg) extinction included several lineages that were absent or poorly represented in Laurasian landmasses. Among these, the South American fossil record contains diverse abelisaurids, arguably the most successful groups of carnivorous dinosaurs from Gondwana in the Cretaceous, reaching their highest diversity towards the end of this period. Here we describe Koleken inakayali gen. et sp. n., a new abelisaurid from the La Colonia Formation (Maastrichtian, Upper Cretaceous) of Patagonia. Koleken inakayali is known from several skull bones, an almost complete dorsal series, complete sacrum, several caudal vertebrae, pelvic girdle and almost complete hind limbs. The new abelisaurid shows a unique set of features in the skull and several anatomical differences from Carnotaurus sastrei (the only other abelisaurid known from the La Colonia Formation). Koleken inakayali is retrieved as a brachyrostran abelisaurid, clustered with other South American abelisaurids from the latest Cretaceous (Campanian-Maastrichtian), such as Aucasaurus, Niebla and Carnotaurus. Leveraging our phylogeny estimates, we explore rates of morphological evolution across ceratosaurian lineages, finding them to be particularly high for elaphrosaurine noasaurids and around the base of Abelisauridae, before the Early Cretaceous radiation of the latter clade. The Noasauridae and their sister clade show contrasting patterns of morphological evolution, with noasaurids undergoing an early phase of accelerated evolution of the axial and hind limb skeleton in the Jurassic, and the abelisaurids exhibiting sustained high rates of cranial evolution during the Early Cretaceous. These results provide much needed context for the evolutionary dynamics of ceratosaurian theropods, contributing to broader understanding of macroevolutionary patterns across dinosaurs.",
    url = "https://doi.org/10.1111/cla.12583",
    doi = "10.1111/cla.12583",
    openalex = "W4398169218",
    references = "doi101002spp21375, doi101016jcretres2019104312, doi101016jcretres2020104408, doi101016jcretres2021104829, doi101038s41598019453069, doi101038s41598022155356, doi101038srep44942, doi101080027246342013776562, doi1010800272463420201877151, doi1010801477201920222093661, doi101111brv12666, doi101111cla12524, doi101111zoj12425, doi1011646zootaxa375911, doi101371journalpone0062047, doi101371journalpone0088905, doi105852crpalevol2020v19a6, doi107717peerj5976"
}