Borogovia Temporal range: Late Cretaceous, | |
---|---|
Leg bones of the holotype | |
Scientific classification | |
Domain: | Eukaryota |
Kingdom: | Animalia |
Phylum: | Chordata |
Clade: | Dinosauria |
Clade: | Saurischia |
Clade: | Theropoda |
Family: | † Troodontidae |
Genus: | † Borogovia Osmólska, 1987 |
Type species | |
†Borogovia gracilicrus Osmólska, 1987 |
Borogovia is a troodontid theropod dinosaur genus which lived during the Late Cretaceous Period, in what is now Mongolia.
In 1971, a Polish-Mongolian expedition discovered the remains of a small theropod at the Altan Ula IV site, in the Nemegt Basin of Ömnögovĭ province. In 1982, upon describing Hulsanpes perlei , the find was reported by Halszka Osmólska and considered by her to be a possible specimen of Saurornithoides . [1] Later she concluded that it represented a species new to science.
In 1987, Osmólska named and described the type species Borogovia gracilicrus. The generic name is derived from the fantasy avian creatures known as 'borogoves' in the Lewis Carroll poem "Jabberwocky", in Through the Looking-Glass . The specific name is a combination of Latin gracilis, "lightly built", and crus, "shin", in reference to the elegant build of the lower leg. [2]
The holotype specimen, ZPAL MgD-I/174, was found in the Nemegt Formation, dating from the early Maastrichtian. It consists of two lower legs of a single individual, including fragments of both tibiotarsi, the undersides of both metatarsi and the second, third and fourth toes of each foot. [2]
The tibiotarsi have an estimated length of twenty-eight centimetres. Borogovia is about two meters (6 feet) long, weighing some twenty kilograms (forty-five pounds). The tibiotarsus is very elongated. The third toe is narrow. The second phalanx of the second toe is short. The claw of the second toe is short and relatively flat. Osmólska claimed that the second toe could not be hyperextended, and suggested that it had regained a weight-bearing function, compensating for the weakness of the third toe. [2] In 2021, Andrea Cau and Daniel Madzia have called this the "falchiporan condition". [3]
Borogovia was assigned by Osmólska to the Troodontidae in 1987. [2]
Troodontidae is a clade of bird-like theropod dinosaurs. During most of the 20th century, troodontid fossils were few and incomplete and they have therefore been allied, at various times, with many dinosaurian lineages. More recent fossil discoveries of complete and articulated specimens, have helped to increase understanding about this group. Anatomical studies, particularly studies of the most primitive troodontids, like Sinovenator, demonstrate striking anatomical similarities with Archaeopteryx and primitive dromaeosaurids, and demonstrate that they are relatives comprising a clade called Paraves.
Deinocheirus is a genus of large ornithomimosaur that lived during the Late Cretaceous around 70 million years ago. In 1965, a pair of large arms, shoulder girdles, and a few other bones of a new dinosaur were first discovered in the Nemegt Formation of Mongolia. In 1970, this specimen became the holotype of the only species within the genus, Deinocheirus mirificus; the genus name is Greek for "horrible hand". No further remains were discovered for almost fifty years, and its nature remained a mystery. Two more complete specimens were described in 2014, which shed light on many aspects of the animal. Parts of these new specimens had been looted from Mongolia some years before, but were repatriated in 2014.
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Bagaceratops is a genus of small protoceratopsid dinosaurs that lived in Asia during the Late Cretaceous, around 72 to 71 million years ago. Bagaceratops remains have been reported from the Barun Goyot Formation and Bayan Mandahu Formation. One specimen may argue the possible presence of Bagaceratops in the Djadochta Formation.
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Tochisaurus is a genus of small troodontid theropod dinosaur from the Late Cretaceous Period of Mongolia. The type species is Tochisaurus nemegtensis.
Bagaraatan is a genus of theropod dinosaur from the Late Cretaceous period. Its fossils were found in the Nemegt Formation of Mongolia. Bagaraatan may have been around 3 to 4 metres in length.
Hulsanpes is a genus of halszkaraptorine theropod dinosaurs that lived during the Late Cretaceous in what is now the Barun Goyot Formation of Mongolia, about 75-72 million years ago. The remains were found in 1970 and formally described in 1982 by Halszka Osmólska, who noted that the genus is represented by an immature individual. Hulsanpes represents the first record of the basal dromaeosaurid subfamily Halszkaraptorinae.
The Barun Goyot Formation is a geological formation dating to the Late Cretaceous Period. It is located within and is widely represented in the Gobi Desert Basin, in the Ömnögovi Province of Mongolia.
The Nemegt Formation is a geological formation in the Gobi Desert of Mongolia, dating to the Late Cretaceous. The formation consists of river channel sediments and contains fossils of fish, turtles, crocodilians, and a diverse fauna of dinosaurs, including birds.
Halszka Osmólska was a Polish paleontologist who had specialized in Mongolian dinosaurs.
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This timeline of troodontid research is a chronological listing of events in the history of paleontology focused on the troodontids, a group of bird-like theropod dinosaurs including animals like Troodon. Troodontid remains were among the first dinosaur fossils to be reported from North America after paleontologists began performing research on the continent, specifically the genus Troodon itself. Since the type specimen of this genus was only a tooth and Troodon teeth are unusually similar to those of the unrelated thick-headed pachycephalosaurs, Troodon and its relatives would be embroiled in taxonomic confusion for over a century. Troodon was finally recognized as distinct from the pachycephalosaurs by Phil Currie in 1987. By that time many other species now recognized as troodontid had been discovered but had been classified in the family Saurornithoididae. Since these families were the same but the Troodontidae named first, it carries scientific legitimacy.
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Ondogurvel is a genus of alvarezsaurid dinosaur from the Late Cretaceous (Campanian) Barun Goyot Formation in southern Mongolia. The type and only species is O. alifanovi, known from a partial skeleton consisting of fragments of two last dorsal vertebrae, three anterior sacral vertebrae, right ilium, left and right pubis and ischium, articulated right tibia, fibula, metatarsals II and IV, and phalanges IV-1 and IV-2, right carpometacarpus, left and right manual phalanx II-1, right femur, left pedal phalanx II-1, and fragments of unidentified phalanges.
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