|
Eotitanosuchidae
Eotitanosuchidae is an extinct family of biarmosuchian therapsids. The Eotitanosuchidae were large predatory therapsids of the Wordian epoch. It was once considered to belong to a separate infraorder of therapsids called Eotitanosuchia. Characteristics The Eotitanosuchians seem to be more advanced than the Biarmosuchia in that the temporal opening behind the eye socket—although small—is still somewhat larger than the biarmosuchians; it is expanded in the upper rear ( posterodorsal) margin, allowing the area of attachment of the adductor ( jaw closing) muscles to be visible from the dorsal (top) view looking down. The eotitanosuchian bite was stronger and more efficient than the biarmosuchian bite. For this reason, some paleontologists see the eotitanosuchids as transitional between the biarmosuchians and higher therapsids. It is at least as likely that features of a larger temporal opening—and hence increased muscle mass and biting power—evolved simultaneously among a nu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ivantosaurus
''Ivantosaurus'' is an extinct genus of therapsid that lived in Russia during the Wordian stage of the Permian period, named in honor of paleontologist Ivan Antonovich Efremov. Description ''Ivantosaurus'' is based on a very fragmentary skull, consisting of 2 partial maxillae and a quadrate. The specimen was discovered in the Perm Region of the Ochersky District, Russia. Fossils from the region date to the Upper Kazanian Substage of the Upper Permian, making it one of the latest Therapsids known. It was carnivorous and may have grown to a length of . ''Ivantosaurus'' would have been the largest carnivorous therapsid known, exceeding in size even the largest Late Wordian/early Capitanian anteosaurs. Teeth Two canine teeth are set side-to-side in ''Ivantosaurus jaw and with their axes inclined forward. It is possible that this therapsid had a unique dentition (no other known animal has two sets of canine teeth), but more likely that a replacement tooth was growing in next to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eotitanosuchus
''Eotitanosuchus'' ("dawn giant crocodile") is an extinct genus of biarmosuchian therapsids whose fossils were found in the town of Ochyor in Perm Krai, Russia. It lived about 267 million years ago. The only species is ''Eotitanosuchus olsoni''. Description ''Eotitanosuchus'' is known from a single large skull without a lower jaw. The skull was , but the overall length may have been over , possibly up to and more than in weight for adult specimens. Like ''Biarmosuchus tener'', it was primitive in that, though it was a predator, the temple opening behind the eye was small, giving it a weak bite. The temple was, however, larger at the top than in other biarmosuchians. Paleoecology ''Eotitanosuchus'' fossils were found in the Perm (or Cis-Urals) region of Russia. ''Eotitanosuchus'' was without doubt a dominant animal of its environment. Found preserved in flood deposits (once coastal bogs) containing many skeletons of estemmenosuchids, it has been suggested that this large preda ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eotitanosuchus Olsoni
''Eotitanosuchus'' ("dawn giant crocodile") is an extinct genus of biarmosuchian therapsids whose fossils were found in the town of Ochyor in Perm Krai, Russia. It lived about 267 million years ago. The only species is ''Eotitanosuchus olsoni''. Description ''Eotitanosuchus'' is known from a single large skull without a lower jaw. The skull was , but the overall length may have been over , possibly up to and more than in weight for adult specimens. Like '' Biarmosuchus tener'', it was primitive in that, though it was a predator, the temple opening behind the eye was small, giving it a weak bite. The temple was, however, larger at the top than in other biarmosuchians. Paleoecology ''Eotitanosuchus'' fossils were found in the Perm (or Cis-Urals) region of Russia. ''Eotitanosuchus'' was without doubt a dominant animal of its environment. Found preserved in flood deposits (once coastal bogs) containing many skeletons of estemmenosuchids, it has been suggested that this large pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biarmosuchians
Biarmosuchians are an extinct clade of non-mammalian synapsids from the Permian. They are the most basal group of the therapsids. All of them were moderately-sized, lightly-built carnivores, intermediate in form between basal sphenacodont "pelycosaurs" and more advanced therapsids. Biarmosuchians were rare components of Permian ecosystems, and the majority of species belong to the clade Burnetiamorpha, which are characterized by elaborate cranial ornamentation. Characteristics The biarmosuchian skull is very similar to the sphenacodontid skull, differing only in the larger temporal fenestra (although these are still small relative to later therapsids), slightly backward-sloping occiput (the reverse of the pelycosaur condition), reduced number of teeth, and single large canine teeth in both upper and lower jaws, and other features (Carroll 1988 pp. 370, Benton 2000 p. 114). In later specialised Biarmosuchia, these resemble the enlarged canines of the Gorgonopsia. The pre ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biarmosuchia
Biarmosuchians are an extinct clade of non-mammalian synapsids from the Permian. They are the most basal group of the therapsids. All of them were moderately-sized, lightly-built carnivores, intermediate in form between basal sphenacodont "pelycosaurs" and more advanced therapsids. Biarmosuchians were rare components of Permian ecosystems, and the majority of species belong to the clade Burnetiamorpha, which are characterized by elaborate cranial ornamentation. Characteristics The biarmosuchian skull is very similar to the sphenacodontid skull, differing only in the larger temporal fenestra (although these are still small relative to later therapsids), slightly backward-sloping occiput (the reverse of the pelycosaur condition), reduced number of teeth, and single large canine teeth in both upper and lower jaws, and other features (Carroll 1988 pp. 370, Benton 2000 p. 114). In later specialised Biarmosuchia, these resemble the enlarged canines of the Gorgonopsia. The pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biarmosuchia
Biarmosuchians are an extinct clade of non-mammalian synapsids from the Permian. They are the most basal group of the therapsids. All of them were moderately-sized, lightly-built carnivores, intermediate in form between basal sphenacodont "pelycosaurs" and more advanced therapsids. Biarmosuchians were rare components of Permian ecosystems, and the majority of species belong to the clade Burnetiamorpha, which are characterized by elaborate cranial ornamentation. Characteristics The biarmosuchian skull is very similar to the sphenacodontid skull, differing only in the larger temporal fenestra (although these are still small relative to later therapsids), slightly backward-sloping occiput (the reverse of the pelycosaur condition), reduced number of teeth, and single large canine teeth in both upper and lower jaws, and other features (Carroll 1988 pp. 370, Benton 2000 p. 114). In later specialised Biarmosuchia, these resemble the enlarged canines of the Gorgonopsia. The pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kamagorgon
''Kamagorgon'' is an extinct genus of therapsids from the Middle Permian of Russia. The type and only species is ''Kamagorgon ulanovi''. It is only known from an incomplete skull. The snout is short and the canine teeth are very large. ''Kamagorgon'' was named in 1998 and originally classified in the biarmosuchian family Eotitanosuchidae along with the poorly known therapsid ''Eotitanosuchus ''Eotitanosuchus'' ("dawn giant crocodile") is an extinct genus of biarmosuchian therapsids whose fossils were found in the town of Ochyor in Perm Krai, Russia. It lived about 267 million years ago. The only species is ''Eotitanosuchus olsoni''. ...''. More recently, ''Kamagorgon'' has considered as a primitive gorgonopsian rather than a biarmosuchian due to the length of the front jawbone and rear side of the skull. These features are commonly shared by the brithopodid and biarmosuchid lineages. References Gorgonopsia Prehistoric therapsid genera Extinct animals of Russia F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wordian
In the geologic timescale, the Wordian is an age or stage of the Permian. It is the middle of three subdivisions of the Guadalupian Epoch or Series. The Wordian lasted between and million years ago (Ma). It was preceded by the Roadian and followed by the Capitanian. Stratigraphy The Wordian Stage was introduced into scientific literature by Johan August Udden in 1916 and was named after the Word Formation of the North American Permian Basin. The Wordian was first used as a stratigraphic subdivision of the Guadalupian in 1961, when both names were still only used regionally in the southern US. The stage was added to the internationally used ISC timescale in 2001.; 1999: ''Proposal of Guadalupian and Component Roadian, Wordian and Capitanian Stages as International Standards for the Middle Permian Series'', Permophiles 34: pp 3–11. The base of the Wordian Stage is defined as the place in the stratigraphic record where fossils of conodont species ''Jinogondolella aserrata'' fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal (anatomy)
Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position provides a definition of what is at the front ("anterior"), behind ("posterior") and so on. As part of defining and describing terms, the body is described through the use of anatomical planes and anatomical axes. The meaning of terms that are used can change depending on whether an organism is bipedal or quadrupedal. Additionally, for some animals such as invertebrates, some terms may not have any meaning at all; for example, an animal that is radially symmetrical will have no anterior surface, but can still have a description that a part is close to the middle ("proximal") or further from the middle ("distal"). International organisations have determined vocabularies that are often used as standard vocabularies for subdisciplines of anatom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guadalupian Extinctions
The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0.5 – 259.1 ± 0.4 Mya. The series saw the rise of the therapsids, a minor extinction event called Olson's Extinction and a significant mass extinction called the end-Capitanian extinction event. The Guadalupian was previously known as the Middle Permian. Name and background The Guadalupian is the second and middle series or epoch of the Permian. Previously called Middle Permian, the name of this epoch is part of a revision of Permian stratigraphy for standard global correlation. The name "Guadalupian" was first proposed in the early 1900s, and approved by the International Subcommission on Permian Stratigraphy in 1996. References to the Middle Permian still exist. The Guadalupian was preceded by the Cisuralian and followed by the Lop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sphenacodont
Sphenacodontia is a stem-based clade of derived synapsids. It was defined by Amson and Laurin (2011) as "the largest clade that includes ''Haptodus baylei'', ''Haptodus garnettensis'' and '' Sphenacodon ferox'', but not ''Edaphosaurus pogonias''". They first appear during the Late Pennsylvanian (Upper Carboniferous) epoch. From the end of the Carboniferous to the end of the Permian, most of them remained large, with only some secondarily becoming small in size. Basal Sphenacodontia constitute a transitional evolutionary series from early pelycosaurs to ancestral therapsids (which in turn were the ancestors of more advanced forms and finally the mammals). One might say that the sphenacodontians are proto-therapsids (even though there is almost a 30-million-years gap between the separation of the ancestors of therapsids from other sphenacodontians and the first appearance of therapsids in the fossil record). Characteristics The defining characteristics include a thickening of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistic
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
