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Boreogomphodon
''Boreogomphodon'' is an extinct genus of traversodontid cynodonts from the Late Triassic of the eastern United States. Fossils have been found from the Turkey Branch Formation in Virginia. Description and history ''Boreogomphodon jeffersoni'' was named in 1990. Its teeth and cranial bones are the most common tetrapod fossils in the Turkey Branch Formation. ''Boreogomphodon'' was distinguished from other traversodontids like the African '' Luangwa'' and the South American ''Traversodon'' on the basis of its postcanine teeth. Most traversodontids have lower postcanine teeth with two cusps, but ''Boreogomphodon'' was the first traversodontid found with three cusps on its lower postcanine teeth. There is a single cusp on the side of the upper postcanine facing the lip, while a flat surface extends outward from it. The traversodontid '' Arctotraversodon'' from the Wolfville Formation of Nova Scotia is similar to ''Boreogomphodon'' in that it has three cusps on its lower postcanine, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turkey Branch Formation
The Doswell Formation (also known as the Doswell Group) is a geologic unit of Upper Triassic age, part of the Newark Supergroup. The Doswell Formation was originally named to refer to a geological sequence which forms the lower part of the sedimentary fill of the Taylorsville Basin in Virginia and Maryland. This sequence was deposited by lakes and rivers in the developing rift basin. However, a 2016 study determined that several geological layers in Pennsylvania as well as the neighboring Richmond Basin of Virginia also qualified as components of the Doswell Formation. The most diverse and fossiliferous component of the Doswell formation is the Vinita member, also sometimes referred to as the Turkey Branch, Tuckahoe, or Falling Creek Formations in earlier publications. The Doswell formation is biostratigraphically characterized by a fauna including the fish '' Dictyopyge macrurus'' and the conchostracan '' Laxitextella multireticulata''. The Richmond Basin has several notable fossi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gomphodontia
Gomphodontia is a clade of cynognathian cynodonts that includes the families Diademodontidae, Trirachodontidae, and Traversodontidae. Gomphodonts are distinguished by wide and closely spaced molar-like postcanine teeth, which are convergent with those of mammals. Other distinguishing characteristics of gomphodonts include deep zygomatic arches, upper postcanines with three or more cusps spanning their widths and lower postcanines with two cusps spanning their widths. Gomphodonts first appeared in the Early Triassic and became extinct at the end of the Late Triassic. Fossils are known from southern Africa, Argentina and southern Brazil (Paleorrota geopark), eastern North America, Europe, China, and Antarctica. Gomphodontia was first named by paleontologist Harry Seeley in 1895. He considered it an order of wide-toothed therapsids (then called anomodonts) from South Africa, distinct from Cynodontia. By the 1930s Gomphodontia was considered a suborder of Cynodontia and included the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traversodontidae
Traversodontidae is an extinct family of herbivorous cynodonts. Traversodonts were primarily Gondwanan, with many species known from Africa and South America. Recently, traversodonts have also been found from Europe and eastern North America. Traversodonts first appeared in the Middle Triassic and diversified in the Late Triassic before going extinct at the end of the epoch. The family Traversodontidae was erected by Friedrich von Huene in 1936 for cynodonts first found in São Pedro do Sul in Paleorrota, Brazil. Description Traversodonts are members of Gomphodontia, a group of herbivorous cynognathian cynodonts. As an adaptation toward eating plants, they have wide postcanine teeth behind large canines. These postcanines are closely spaced with their crowns touching each other. Each is usually wider than it is long and is covered in several cusps. Because of their complexity, postcanine teeth are the primary means of identifying and distinguishing different species of traverso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Massetognathus
''Massetognathus'' ( ; Greek for "chewing muscle jaw") is an extinct genus of plant-eating traversodontid cynodonts. They lived during the Triassic Period about 235 million years ago, and are known from the Chañares Formation in Argentina and the Santa Maria Formation in Brazil. Description ''Massetognathus'' species measured to about in length with an estimated weight between . ''Massetognathus'' was the smaller, plant-eating equivalent of the better-known '' Cynognathus'' with incisors, fang-like canines and flat-topped molars covered by low ridges, an adaptation for grinding tough plant stems, roots, and other plant materials. It had a low and flattened skull indicating that the specimen had a relatively shorter and broader snout than larger specimens. It was a fox sized animal with claws on its feet and a long dog-like tail. Like most cynodonts, there is some evidence that they laid eggs, were warm blooded, as indicated by the detailed structure of the bones, and had a b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traversodontid
Traversodontidae is an extinct family of herbivorous cynodonts. Traversodonts were primarily Gondwanan, with many species known from Africa and South America. Recently, traversodonts have also been found from Europe and eastern North America. Traversodonts first appeared in the Middle Triassic and diversified in the Late Triassic before going extinct at the end of the epoch. The family Traversodontidae was erected by Friedrich von Huene in 1936 for cynodonts first found in São Pedro do Sul in Paleorrota, Brazil. Description Traversodonts are members of Gomphodontia, a group of herbivorous cynognathian cynodonts. As an adaptation toward eating plants, they have wide postcanine teeth behind large canines. These postcanines are closely spaced with their crowns touching each other. Each is usually wider than it is long and is covered in several cusps. Because of their complexity, postcanine teeth are the primary means of identifying and distinguishing different species of traverso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynodont
The cynodonts () (clade Cynodontia) are a clade of eutheriodont therapsids that first appeared in the Late Permian (approximately 260 mya), and extensively diversified after the Permian–Triassic extinction event. Cynodonts had a wide variety of lifestyles, including carnivory and herbivory. Mammals are cynodonts, as are their extinct ancestors and close relatives, having evolved from advanced probainognathian cynodonts during the Late Triassic. All other cynodont lines went extinct, with the last known non-mammalian cynodont group, the Tritylodontidae, having its youngest records in the Early Cretaceous. Description Early cynodonts have many of the skeletal characteristics of mammals. The teeth were fully differentiated and the braincase bulged at the back of the head. Outside of some crown-group mammals (notably the therians), all cynodonts probably laid eggs. The temporal fenestrae were much larger than those of their ancestors, and the widening of the zygomatic arch in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctotraversodon
''Arctotraversodon'' is an extinct genus of traversodontid cynodonts from the Late Triassic of Canada. Fossils first described from the Wolfville Formation in Nova Scotia in 1984 represented the first known traversodontid from North America.Hopson, J.A. (1984). Late Triassic traversodont cynodonts from Nova Scotia and southern Africa. ''Palaeontologia Africana'' Vol. 25; 181-201. The type and only species is ''A. plemmyridon'' and is represented by teeth and several dentary bones. Description and history ''Arctotraversodon'' was first tentatively placed in the genus ''Scalenodontoides'' as a new species, ?''Scalenodontoides plemmyridon''. Only dentary bones and a few teeth were known when it was first named. Postcanine teeth, the primary diagnostic material of most traversodontids, were not known for ?''S. plemmyridon''. Few available features could diagnose ?''S. plemmyridon'' as its own species, but the bones and teeth were clearly different from those of other traversodontids. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diademodontidae
Diademodontidae is an extinct family of Triassic gomphodonts. The best-known genus is ''Diademodon'' from South Africa. '' Titanogomphodon'' from Namibia may also be a member of Diademodontidae. The Chinese genera '' Hazhenia'' and '' Ordosiodon'' have also been included in the family, but were more recently identified as baurioid therocephalians. Remains of a diademodontid were reported in the Early-Middle Triassic Fremouw Formation in Antarctica, but that specimen was later referred to the trirachodontid ''Impidens ''Impidens'' is an extinct genus of large omnivorous cynodont from the Triassic of South Africa and Antarctica. Its type and only species is ''Impidens hancoxi''. ''Impidens'' inhabited high-latitude environments of southern Gondwana during the ...'' References Cynognathians Early Triassic first appearances Late Triassic extinctions Prehistoric therapsid families {{paleo-therapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Trirachodontidae
Trirachodontidae is an extinct, possibly paraphyletic family of cynognathian cynodonts from the Triassic of China and southern Africa. Trirachodontids appeared during the Early Triassic soon after the Permian-Triassic extinction event and quickly spread over a wide geographic area in a comparatively brief amount of time from 250 to 237 million years ago. Trirachodontids have wide skulls and short, narrow snouts. Two large holes called temporal fenestrae run along the back of the head and have a uniformly large width. Trirachodontids also have two large canine teeth and smaller cusped postcanines. Most of the features that distinguish trirachodonts from other cynodonts are found in their dentition. Trirachodontids lived in semi-arid environments with seasonal rainfall. The bone structure of trirachodontids suggests that they grew quickly in seasons with high rainfall and slowly in less favorable seasons. One trirachodontid, '' Trirachodon'', has been found in association with com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series (stratigraphy), series of rock beds is known as the Upper Triassic. The Late Triassic is divided into the Carnian, Norian and Rhaetian Geologic time scale, Ages. Many of the first dinosaurs evolved during the Late Triassic, including ''Plateosaurus'', ''Coelophysis'', and ''Eoraptor''. The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. Etymology The Triassic was named in 1834 by Friedrich August von Namoh, Friedrich von Alberti, after a succession of three distinct rock layers (Greek meaning 'triad') that are widespread in southern Germany: the lower Buntsandstein (colourful sandstone'')'', t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Andescynodon
''Andescynodon'' is a genus of traversodontid cynodonts from the Middle Triassic of Argentina. Fossils are known from the Cerro de las Cabras and Cacheutá Formations. ''Andescynodon'' is one of the most basal traversodontids. Another traversodontid called ''Rusconiodon'' has also been identified from the Cerro de las Cabras Formation but is now considered a junior synonym of ''Andescynodon''. Description and history The type species ''Andescynodon mendozensis'' was named in 1967 and reported from the Rio Mendoza Formation. The location where remains have been found was later shown to be part of the Cerro de las Cabras Formation. Like all traversodontids, ''Andescynodon'' has wide postcanine teeth at the back of its jaws. These wide teeth are seen as evidence of a herbivorous diet and give traversodontids their name (their teeth are transversely wide). One distinguishing feature of ''Andescynodon'' is the forward position of a ridge on these postcanine teeth. The temporal r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pascualgnathus
''Pascualgnathus'' is an extinct genus of traversodontid cynodonts from the Middle Triassic of Argentina. Fossils have been found from the Río Seco de la Quebrada Formation of the Puesto Viejo Group. The type species ''P. polanskii'' was named in 1966. Description ''Pascualgnathus'' is a small traversodontid. It has large upper canine teeth and small postcanine teeth. The postcanine teeth of ''Pascualgnathus'' and other traversodontids are wide, allowing them to eat plant material. The upper postcanines of ''Pascualgnathus'' are rectangular. Each has a central ridge and a cusp on the side facing the mouth. There are also two cusps on the side of the tooth facing the lips, with one being larger than the other. The lower postcanines have less of a rectangular shape and have only two cusps. Unlike the upper postcanines, they are longer than they are wide. Classification When ''Pascualgnathus'' was first named in 1966, it was considered a member of the family Diademodontidae more c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
