Troodontids

@misc{barsbold1987on1,
    author = "Barsbold, R. and Osmolska, H. and Kurzanov, S. M",
    title = "On a new troodontid (Dinosauria, Theropoda) from the Early Cretaceous of Mongolia",
    year = "1987",
    howpublished = "Acta Palaeontologica Polonica, v. 32, p. 121-132",
    note = "talkorigins\_source = {true}; raw\_reference = {Barsbold, R., Osmolska, H., and Kurzanov, S. M., 1987, On a new troodontid (Dinosauria, Theropoda) from the Early Cretaceous of Mongolia: Acta Palaeontologica Polonica, v. 32, p. 121-132.}"
}

@article{currie1987birdlike,
    author = "Currie, Philip J.",
    title = "Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia)",
    year = "1987",
    journal = "Journal of Vertebrate Paleontology",
    url = "https://doi.org/10.1080/02724634.1987.10011638",
    doi = "10.1080/02724634.1987.10011638",
    number = "1",
    pages = "72-81",
    volume = "7"
}

@article{currie1987birdlike2,
    author = "Currie, P. J",
    title = "Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia)",
    year = "1987",
    journal = "Journal of Vertebrate Paleontology, v. 7, p. 72-81",
    note = "talkorigins\_source = {true}; raw\_reference = {Currie, P. J., 1987, Bird-like characteristics of the jaws and teeth of troodontid theropods (Dinosauria, Saurischia): Journal of Vertebrate Paleontology, v. 7, p. 72-81.}"
}

@misc{osmolska1987borogovia3,
    author = "Osmolska, H",
    title = "Borogovia gracilicrus gen. et sp. n., a new troodontid dinosaur from the Late Cretaceous of Mongolia",
    year = "1987",
    howpublished = "Acta Palaeontologica Polonica, v. 32, p. 133-150",
    note = "talkorigins\_source = {true}; raw\_reference = {Osmolska, H., 1987, Borogovia gracilicrus gen. et sp. n., a new troodontid dinosaur from the Late Cretaceous of Mongolia: Acta Palaeontologica Polonica, v. 32, p. 133-150.}"
}

Troodontid specimens were recovered from three localities in China by the Sino-Canadian expeditions between 1987 and 1990. These include a Lower Cretaceous form (Sinornithoides youngi), which is the most complete troodontid skeleton ever found, isolated bones from the Iren Dabasu Formation (?Turonian), and partial skeletons of Saurornithoides mongoliensis from Djadokhta-equivalent beds (?Campanian). These, and other specimens recently described from North America, allow a better assessment of the phylogenetic position of troodontids than has been possible before. Although troodontids have autapomorphies that eliminate them from consideration as bird ancestors, they are nevertheless one of the closest avian outgroups within the Theropoda.

@article{currie2001new,
    author = "Currie, Philip J and Zhiming, Dong",
    title = "New information on Cretaceous troodontids (Dinosauria, Theropoda) from the People's Republic of China",
    year = "2001",
    journal = "Canadian Journal of Earth Sciences",
    abstract = "Troodontid specimens were recovered from three localities in China by the Sino-Canadian expeditions between 1987 and 1990. These include a Lower Cretaceous form (Sinornithoides youngi), which is the most complete troodontid skeleton ever found, isolated bones from the Iren Dabasu Formation (?Turonian), and partial skeletons of Saurornithoides mongoliensis from Djadokhta-equivalent beds (?Campanian). These, and other specimens recently described from North America, allow a better assessment of the phylogenetic position of troodontids than has been possible before. Although troodontids have autapomorphies that eliminate them from consideration as bird ancestors, they are nevertheless one of the closest avian outgroups within the Theropoda.",
    url = "https://doi.org/10.1139/e01-065",
    doi = "10.1139/e01-065",
    number = "12",
    pages = "1753-1766",
    volume = "38"
}

@article{norell2004a,
    author = "NORELL, MARK A. and HWANG, SUNNY H.",
    title = "A Troodontid Dinosaur from Ukhaa Tolgod (Late Cretaceous Mongolia)",
    year = "2004",
    journal = "American Museum Novitates",
    url = "https://doi.org/10.1206/0003-0082(2004)446<0001:atdfut>2.0.co;2",
    doi = "10.1206/0003-0082(2004)446<0001:atdfut>2.0.co;2",
    pages = "1-9",
    volume = "3446"
}

@article{lü2010a,
    author = "Lü, Junchang and Xu, Li and Liu, Yongqing and Zhang, Xingliao and Jia, Songhai and Ji, Qiang",
    title = "A New Troodontid Theropod from the Late Cretaceous of Central China, and the Radiation of Asian Troodontids",
    year = "2010",
    journal = "Acta Palaeontologica Polonica",
    url = "https://doi.org/10.4202/app.2009.0047",
    doi = "10.4202/app.2009.0047",
    number = "3",
    pages = "381-388",
    volume = "55"
}

@article{xu2011a,
    author = "Xu, Xing and Tan, Qingwei and Sullivan, Corwin and Han, Fenglu and Xiao, Dong",
    title = "A Short-Armed Troodontid Dinosaur from the Upper Cretaceous of Inner Mongolia and Its Implications for Troodontid Evolution",
    year = "2011",
    journal = "PLoS ONE",
    url = "https://doi.org/10.1371/journal.pone.0022916",
    doi = "10.1371/journal.pone.0022916",
    number = "9",
    pages = "e22916",
    volume = "6"
}

@article{tsuihiji2016new,
    author = "Tsuihiji, Takanobu and Barsbold, Rinchen and Watabe, Mahito and Tsogtbaatar, Khishigjav and Suzuki, Shigeru and Hattori, Soki",
    title = "New material of a troodontid theropod (Dinosauria: Saurischia) from the Lower Cretaceous of Mongolia",
    year = "2016",
    journal = "Historical Biology",
    url = "https://doi.org/10.1080/08912963.2015.1005086",
    doi = "10.1080/08912963.2015.1005086",
    number = "1-2",
    pages = "128-138",
    volume = "28"
}

A new small-bodied troodontid (LH PV39) recovered from the Upper Cretaceous Wulansuhai Formation, Suhongtu, Inner Mongolia, China, is described. The new specimen preserves six postaxial cervical vertebrae, five completely fused sacral and four posterior caudal vertebrae in addition to two manual unguals. The completely fused neurocentral junctions indicate that a skeletally mature individual of the same species of LH PV39 would be smaller than Philovenator and comparable in body size to a skeletal mature individual of Almas. The extremely dorsoventrally compressed sacral centra and neural canal, and the middle three sacral centra that are shorter and wider than the first and the last one distinguishing LH PV39 from other known troodontids. A series of phylogenetic analyses were conducted using modified published matrices. By coding LH PV39 in different strategies, the troodontid affinity of LH PV39 is confirmed and it was recovered as the sister taxon of either Mei and Sinovenator (LH PV39 scored as a separate OTU) or Linhevenator (incorporating LH PV39 into Philovenator) in the best resolved coelurosaurian interrelationships. The referral of LH PV39 to Philovenator does not seriously alter the phylogenetic position of Philovenator nor the interrelationships of troodontids. This new finding confirms that the small and large sized troodontids are coexisted in the Gobi Desert of the Mongolia Plateau until the end of Cretaceous.

@misc{wang2020a,
    author = "Wang, Shuo and Tan, Qingwei and Zhang, Qiyue and Steigler, Josef and Zhang, Huitao and Tan, Lin",
    title = "A Small-Bodied Troodontid (Dinosauria, Theropoda) from the Upper Cretaceous Wulansuhai Formation of Inner Mongolia, China",
    year = "2020",
    abstract = "A new small-bodied troodontid (LH PV39) recovered from the Upper Cretaceous Wulansuhai Formation, Suhongtu, Inner Mongolia, China, is described. The new specimen preserves six postaxial cervical vertebrae, five completely fused sacral and four posterior caudal vertebrae in addition to two manual unguals. The completely fused neurocentral junctions indicate that a skeletally mature individual of the same species of LH PV39 would be smaller than Philovenator and comparable in body size to a skeletal mature individual of Almas. The extremely dorsoventrally compressed sacral centra and neural canal, and the middle three sacral centra that are shorter and wider than the first and the last one distinguishing LH PV39 from other known troodontids. A series of phylogenetic analyses were conducted using modified published matrices. By coding LH PV39 in different strategies, the troodontid affinity of LH PV39 is confirmed and it was recovered as the sister taxon of either Mei and Sinovenator (LH PV39 scored as a separate OTU) or Linhevenator (incorporating LH PV39 into Philovenator) in the best resolved coelurosaurian interrelationships. The referral of LH PV39 to Philovenator does not seriously alter the phylogenetic position of Philovenator nor the interrelationships of troodontids. This new finding confirms that the small and large sized troodontids are coexisted in the Gobi Desert of the Mongolia Plateau until the end of Cretaceous.",
    url = "https://doi.org/10.1101/2020.02.05.936526",
    doi = "10.1101/2020.02.05.936526"
}

Borogovia gracilicrus is a small-bodied theropod dinosaur from the Maastrichtian (Upper Cretaceous) Nemegt Formation of southern Mongolia. The taxon is based on a single fragmentary specimen preserving only the distal part of the hindlimbs. The morphology of Borogovia shows a peculiar combination of features, some of which are traditionally considered troodontid synapomorphies and others which are unusual for Troodontidae but are shared with other maniraptoran clades. In particular, the second toe of B. gracilicrus differs from other troodontids in lacking some of the features which contribute to the specialized ‘sickle-clawed’ second toe, here termed the ‘falciphoran condition’, shared with dromaeosaurids and some other paravians, such as the strongly compressed and falciform ungual. Phylogeny reconstructions intended to explore the affinities of Borogovia consistently support its referral within a subclade of troodontids including all Late Cretaceous taxa. The placement of Borogovia is not significantly affected by its unusual combinations of hindlimb features or by the homoplasy of the elements forming the falciphoran condition. Borogovia is supported as a valid taxon and is distinct from the other Nemegt troodontids, Tochisaurus and Zanabazar. The lack of a falciform ungual, and the distinctive morphology of the second toe in B. gracilicrus are interpreted as a derived specialization among Troodontidae and not as retention of the plesiomorphic condition of non-paravian theropods.

@article{cau2021the,
    author = "Cau, Andrea and Madzia, Daniel",
    title = "The phylogenetic affinities and morphological peculiarities of the bird-like dinosaur Borogovia gracilicrus from the Upper Cretaceous of Mongolia",
    year = "2021",
    journal = "PeerJ",
    abstract = "Borogovia gracilicrus is a small-bodied theropod dinosaur from the Maastrichtian (Upper Cretaceous) Nemegt Formation of southern Mongolia. The taxon is based on a single fragmentary specimen preserving only the distal part of the hindlimbs. The morphology of Borogovia shows a peculiar combination of features, some of which are traditionally considered troodontid synapomorphies and others which are unusual for Troodontidae but are shared with other maniraptoran clades. In particular, the second toe of B. gracilicrus differs from other troodontids in lacking some of the features which contribute to the specialized ‘sickle-clawed’ second toe, here termed the ‘falciphoran condition’, shared with dromaeosaurids and some other paravians, such as the strongly compressed and falciform ungual. Phylogeny reconstructions intended to explore the affinities of Borogovia consistently support its referral within a subclade of troodontids including all Late Cretaceous taxa. The placement of Borogovia is not significantly affected by its unusual combinations of hindlimb features or by the homoplasy of the elements forming the falciphoran condition. Borogovia is supported as a valid taxon and is distinct from the other Nemegt troodontids, Tochisaurus and Zanabazar. The lack of a falciform ungual, and the distinctive morphology of the second toe in B. gracilicrus are interpreted as a derived specialization among Troodontidae and not as retention of the plesiomorphic condition of non-paravian theropods.",
    url = "https://doi.org/10.7717/peerj.12640",
    doi = "10.7717/peerj.12640",
    pages = "e12640",
    volume = "9"
}

A characteristic fauna of dinosaurs and other vertebrates inhabited the end-Cretaceous European archipelago, some of which were dwarves or had other unusual features likely related to their insular habitats. Little is known, however, about the contemporary theropod dinosaurs, as they are represented mostly by teeth or other fragmentary fossils. A new isolated theropod metatarsal II, from the latest Maastrichtian of Spain (within 200,000 years of the mass extinction) may represent a jinfengopterygine troodontid, the first reported from Europe. Comparisons with other theropods and phylogenetic analyses reveal an autapomorphic foramen that distinguishes it from all other troodontids, supporting its identification as a new genus and species, Tamarro insperatus. Bone histology shows that it was an actively growing subadult when it died but may have had a growth pattern in which it grew rapidly in early ontogeny and attained a subadult size quickly. We hypothesize that it could have migrated from Asia to reach the Ibero-Armorican island no later than Cenomanian or during the Maastrichtian dispersal events.

@article{sellés2021a,
    author = "Sellés, Albert G. and Vila, Bernat and Brusatte, Stephen L. and Currie, Philip J. and Galobart, Àngel",
    title = "A fast-growing basal troodontid (Dinosauria: Theropoda) from the latest Cretaceous of Europe",
    year = "2021",
    journal = "Scientific Reports",
    abstract = "A characteristic fauna of dinosaurs and other vertebrates inhabited the end-Cretaceous European archipelago, some of which were dwarves or had other unusual features likely related to their insular habitats. Little is known, however, about the contemporary theropod dinosaurs, as they are represented mostly by teeth or other fragmentary fossils. A new isolated theropod metatarsal II, from the latest Maastrichtian of Spain (within 200,000 years of the mass extinction) may represent a jinfengopterygine troodontid, the first reported from Europe. Comparisons with other theropods and phylogenetic analyses reveal an autapomorphic foramen that distinguishes it from all other troodontids, supporting its identification as a new genus and species, Tamarro insperatus. Bone histology shows that it was an actively growing subadult when it died but may have had a growth pattern in which it grew rapidly in early ontogeny and attained a subadult size quickly. We hypothesize that it could have migrated from Asia to reach the Ibero-Armorican island no later than Cenomanian or during the Maastrichtian dispersal events.",
    url = "https://doi.org/10.1038/s41598-021-83745-5",
    doi = "10.1038/s41598-021-83745-5",
    number = "1",
    volume = "11"
}

@article{lee2023the,
    author = "Lee, Sungjin and Lee, Yuong-Nam and Park, Jin-Young and Kim, Su-Hwan and Badamkhatan, Zorigt and Idersaikhan, Damdinsuren and Tsogtbaatar, Khishigjav",
    title = "The first troodontid (Dinosauria: Theropoda) from the Upper Cretaceous Baruungoyot Formation of Mongolia",
    year = "2023",
    journal = "Journal of Vertebrate Paleontology",
    url = "https://doi.org/10.1080/02724634.2024.2364746",
    doi = "10.1080/02724634.2024.2364746",
    number = "6",
    volume = "43"
}