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Shuotheriidae
Shuotheriidae is a small family of Jurassic mammaliaforms whose remains are found in China, Great Britain and possibly Russia. They have been proposed to be close relatives of Australosphenida (which often controversially includes monotremes), together forming the clade Yinotheria. However, some studies suggest shuotheres are closer to therians than to monotremes, or that australosphenidans and therians are more closely related to each other than either are to shuotheres, with a 2024 study suggesting that shuotheriids were closely related to Docodonta Docodonta is an Order (biology), order of extinct Mesozoic Mammaliaformes, mammaliaforms (advanced cynodonts closely related to true Crown group, crown-group mammals). They were among the most common mammaliaforms of their time, persisting from t ... outside of the Mammalia crown group. References Further reading * Zofia Kielan-Jaworowska, Richard L. Cifelli, and Zhe-Xi Luo, ''Mammals from the Age of Dinosaurs: Origins, Evolu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yinotheria
Yinotheria is a proposed basal subclass clade of crown mammals uniting the Shuotheriidae, an extinct group of mammals from the Jurassic of Eurasia, with Australosphenida, a group of mammals known from the Jurassic to Cretaceous of Gondwana, which possibly include living monotremes. Today, there are only five surviving species of monotremes which live in Australia and New Guinea, consisting of the platypus and four species of echidna. Fossils of yinotheres have been found in United Kingdom, Britain, China, Russia, Madagascar and Argentina. Contrary to other known crown mammals, they retained postdentary bones as shown by the presence of a postdentary trough. The extant members (monotremes) developed the mammalian middle ear independently. Other studies have rejected Yinotheria, finding Shuotheriidae to be unrelated to Australosphenida and outside crown Mammalia. Evolutionary history According to genetic studies, Yinotheria diverged from other mammals around 220 to 210 million years ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shuotherium Dongi
''Shuotherium'' is a fossil mammaliaform known from Middle-Late Jurassic of the Forest Marble Formation of England,Sigogneau−Russell, D. 1998. Discovery of a Late Jurassic Chinese mammal in the upper Bathonian of England. Comptes Rendus de l’Académie des Sciences, Paris 327: 571–576 and the Shaximiao Formation of Sichuan, China.M. Chow and T. H. V. Rich. 1982. Shuotherium dongi, n. gen. and sp., a therian with pseudo-tribosphenic molars from the Jurassic of Sichuan, China. Australian Mammalogy 54:127-142Kielan-Jaworowska, Z.; Cifelli, R.L.; Luo, Z.−X. (2002). "Dentition and relationships of the Jurassic mammal Shuotherium" (PDF). Acta Palaeontologica Polonica. 47 (3): 479–86 The original holotype is composed of a partial dentary and seven teeth (two which are incomplete). The holotypes for other species of this genus are solely represented by isolated molars. ''Shuotherium'', along with ''Pseudotribos'' has been placed in the family Shuotheriidae as a sister taxon of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shuotherium
''Shuotherium'' is a fossil mammaliaform known from Middle Jurassic, Middle-Late Jurassic of the Forest Marble Formation of England,Sigogneau−Russell, D. 1998. Discovery of a Late Jurassic Chinese mammal in the upper Bathonian of England. Comptes Rendus de l’Académie des Sciences, Paris 327: 571–576 and the Shaximiao Formation of Sichuan, China.M. Chow and T. H. V. Rich. 1982. Shuotherium dongi, n. gen. and sp., a therian with pseudo-tribosphenic molars from the Jurassic of Sichuan, China. Australian Mammalogy 54:127-142Kielan-Jaworowska, Z.; Cifelli, R.L.; Luo, Z.−X. (2002). "Dentition and relationships of the Jurassic mammal Shuotherium" (PDF). Acta Palaeontologica Polonica. 47 (3): 479–86 The original holotype is composed of a partial dentary and seven teeth (two which are incomplete). The holotypes for other species of this genus are solely represented by isolated molars. ''Shuotherium'', along with ''Pseudotribos'' has been placed in the family Shuotheriidae as a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammaliaforms
Mammaliaformes ("mammalian forms") is a clade of synapsid tetrapods that includes the crown group mammals and their closest extinct relatives; the group radiated from earlier probainognathian cynodonts during the Late Triassic. It is defined as the clade originating from the most recent common ancestor of Morganucodonta and the crown group mammals; the latter is the clade originating with the most recent common ancestor of extant Monotremata, Marsupialia and Placentalia. Besides Morganucodonta and the crown group mammals, Mammaliaformes also includes Docodonta and ''Hadrocodium''. Mammaliaformes is a term of phylogenetic nomenclature. In contrast, the assignment of organisms to class Mammalia has traditionally been founded on traits and, on this basis, Mammalia is slightly more inclusive than Mammaliaformes. In particular, trait-based taxonomy generally includes ''Adelobasileus'' and '' Sinoconodon'' in Mammalia, though they fall outside the Mammaliaformes definition. These gen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shuotheriidae
Shuotheriidae is a small family of Jurassic mammaliaforms whose remains are found in China, Great Britain and possibly Russia. They have been proposed to be close relatives of Australosphenida (which often controversially includes monotremes), together forming the clade Yinotheria. However, some studies suggest shuotheres are closer to therians than to monotremes, or that australosphenidans and therians are more closely related to each other than either are to shuotheres, with a 2024 study suggesting that shuotheriids were closely related to Docodonta Docodonta is an Order (biology), order of extinct Mesozoic Mammaliaformes, mammaliaforms (advanced cynodonts closely related to true Crown group, crown-group mammals). They were among the most common mammaliaforms of their time, persisting from t ... outside of the Mammalia crown group. References Further reading * Zofia Kielan-Jaworowska, Richard L. Cifelli, and Zhe-Xi Luo, ''Mammals from the Age of Dinosaurs: Origins, Evolu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Docodonta
Docodonta is an Order (biology), order of extinct Mesozoic Mammaliaformes, mammaliaforms (advanced cynodonts closely related to true Crown group, crown-group mammals). They were among the most common mammaliaforms of their time, persisting from the Early Jurassic to the Early Cretaceous across the continent of Laurasia (modern-day North America, Europe, and Asia). They are distinguished from other early mammaliaforms by their relatively complex Molar (tooth), molar teeth. Docodontan teeth have been described as "pseudotribosphenic": a cusp on the inner half of the upper molar grinds into a basin on the front half of the lower molar, like a Mortar and pestle, mortar-and-pestle. This is a case of convergent evolution with the Tribosphenic molar, tribosphenic teeth of therian mammals. There is much uncertainty for how docodontan teeth developed from their simpler ancestors. Their closest relatives may have been certain Triassic "Symmetrodonta, symmetrodonts", namely ''Woutersia'', an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudotribos
''Pseudotribos'' ("false chewing") is an extinct genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ... of mammaliaform that lived in Northern China during the Middle Jurassic some , possibly more closely related to monotremes than to theria ( placental and marsupial mammals), although other studies indicate that these shuotheres are closer to therians than to monotremes. The only known specimen was found in the Daohugou Bed in Inner Mongolia (: paleocoordinates ).. Retrieved May 2013. References External links ''Pseudotribos robustus'', ancient Jurassic mammal with new type of teeth Shuotheriidae Middle Jurassic synapsids of Asia Fossil taxa described in 2007 Taxa named by Zhe-Xi Luo Taxa named by Qiang Ji (paleontologist) Taxa named by Chong-Xi Yuan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Itatodon
''Itatodon'' is an extinct genus of primitive mammaliaforms known from the Bathonian aged Itat Formation of Russia. The genus is named after the formation, with the species being named after Leonid Petrovich Tatarinov who described the first docodont from Asia. It is known from a holotype right lower molar and referred isolated right lower molar and fragment of the left lower molar. When it was first described, it was thought to be a docodontan, but one recent phylogenetic studies have assigned it, along with its close relative '' Paritatodon'' to Shuotheriidae Shuotheriidae is a small family of Jurassic mammaliaforms whose remains are found in China, Great Britain and possibly Russia. They have been proposed to be close relatives of Australosphenida (which often controversially includes monotremes), t ..., while others continue to consider it a docodont. References Shuotheriidae Bathonian life Middle Jurassic synapsids of Asia Jurassic Russia Fossils of Russia F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paritatodon
''Paritatodon'' is an extinct mammaliaform which existed in Kyrgyzstan and England during the Jurassic period. It was originally the holotype specimen of ''Shuotherium kermacki'', but Martin and Averianov (2010) argued that it resembled the genus ''Itatodon'' (Docodonta) and so renamed it ''Paritatodon''. Nonetheless, some recent phylogenetic studies assign it (and ''Itatodon'') to Shuotheriidae,Wang, Y.-Q. and Li, C.-K. 2016. Reconsideration of the systematic position of the Middle Jurassic mammaliaforms Itatodon and Paritatodon. Palaeontologia Polonica 67, 249–256. while others continue to consider the taxon a docodont. Like many Mesozoic mammals, this species is only known from its teeth, in this case two lower molars from the Forest Marble Formation in England, and a single left lower molar from the Balabansai Formation The Balabansai Formation (sometimes transcribed Balabansay, also known as Balabansai Svita) is a geological formation in Kazakhstan, Kyrgyzstan and Uzb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feredocodon
''Feredocodon'' is an extinct genus of mammaliaform that lived during the Middle Jurassic between 168 and 164 million years ago. It was discovered in China, Inner Mongolia Inner Mongolia, officially the Inner Mongolia Autonomous Region, is an Autonomous regions of China, autonomous region of China. Its border includes two-thirds of the length of China's China–Mongolia border, border with the country of Mongolia. ..., in Daohugou locality. References Shuotheriidae Middle Jurassic synapsids of Asia Fossil taxa described in 2024 Prehistoric cynodont genera {{Paleo-cynodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Jurassic
The Middle Jurassic is the second Epoch (geology), epoch of the Jurassic Period (geology), Period. It lasted from about 174.1 to 161.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland,British Geological Survey. 2011Stratigraphic framework for the Middle Jurassic strata of Great Britain and the adjoining continental shelf: research report RR/11/06 British Geological Survey, Keyworth, Nottingham. the Calcaire de Caen of France, the Daohugou Beds in China, the Itat Formation in Russia, the Tiouraren Formation of Niger, and the Isalo III Formation of western Madagascar. Rocks of the Middle Jurassic were formerly (until about 1980s) in Europe called ''Dogger'' or ''Brown Jurassic''. Paleogeography During the Middle Jurassic Epoch, Pangaea began to separate into Laurasia and Gond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
