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Mammaliamorph
Mammaliamorpha is a clade of cynodonts. It contains the clades Tritylodontidae and Mammaliaformes, as well as a few genera that do not belong to either of these groups. The family Tritheledontidae has also been placed in Mammaliamorpha by some phylogenetic analyses, but has been recovered outside the clade by others. According to a 2022 study based on inner ear anatomy, Mammaliamorpha may be the clade in which endothermy ("warm-bloodedness") first appeared in the mammalian lineage. Classification Mammaliamorpha was named in 1988 by the American palaeontologist Timothy B. Rowe, who defined it as comprising "the last common ancestor of Tritylodontidae and Mammalia, and all its descendants". The cladogram below is adapted from the 2019 description of the mammaliamorph ''Pseudotherium ''Pseudotherium'' ("false beast") is an extinct genus of mammaliamorph cynodonts from the Late Triassic of Argentina. It contains one species, ''P. argentinus'', which was first described in 2019 f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brasilitherium
''Brasilodon'' ("tooth from Brazil") is an extinct genus of small, mammal-like cynodonts that lived in what is now Brazil during the Norian age of the Late Triassic epoch, about 225.42 million years ago. While no complete skeletons have been found, the length of ''Brasilodon'' has been estimated at around . Its dentition shows that it was most likely an insectivore. The genus is monotypic, containing only the species ''B. quadrangularis''. ''Brasilodon'' belongs to the family Brasilodontidae, whose members were some of the closest relatives of mammals, the only cynodonts alive today. Two other brasilodontid genera, ''Brasilitherium'' and ''Minicynodon'', are now considered to be junior synonyms of ''Brasilodon''. Discovery and naming The first three specimens referred to ''Brasilodon quadrangularis'' were found at the Linha São Luiz site, a quarry near the town of Faxinal do Soturno in the state of Rio Grande do Sul. The rocks where ''Brasilodon'' was found belong to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brasilodon
''Brasilodon'' ("tooth from Brazil") is an extinct genus of small, mammal-like cynodonts that lived in what is now Brazil during the Norian age of the Late Triassic epoch, about 225.42 million years ago. While no complete skeletons have been found, the length of ''Brasilodon'' has been estimated at around . Its dentition shows that it was most likely an insectivore. The genus is monotypic, containing only the species ''B. quadrangularis''. ''Brasilodon'' belongs to the family Brasilodontidae, whose members were some of the closest relatives of mammals, the only cynodonts alive today. Two other brasilodontid genera, ''Brasilitherium'' and ''Minicynodon'', are now considered to be junior synonyms of ''Brasilodon''. Discovery and naming The first three specimens referred to ''Brasilodon quadrangularis'' were found at the Linha São Luiz site, a quarry near the town of Faxinal do Soturno in the state of Rio Grande do Sul. The rocks where ''Brasilodon'' was found belong to the uppe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brasilodontidae
''Brasilodon'' ("tooth from Brazil") is an extinct genus of small, mammal-like cynodonts that lived in what is now Brazil during the Norian age of the Late Triassic epoch, about 225.42 million years ago. While no complete skeletons have been found, the length of ''Brasilodon'' has been estimated at around . Its dentition shows that it was most likely an insectivore. The genus is monotypic, containing only the species ''B. quadrangularis''. ''Brasilodon'' belongs to the family Brasilodontidae, whose members were some of the closest relatives of mammals, the only cynodonts alive today. Two other brasilodontid genera, ''Brasilitherium'' and ''Minicynodon'', are now considered to be junior synonyms of ''Brasilodon''. Discovery and naming The first three specimens referred to ''Brasilodon quadrangularis'' were found at the Linha São Luiz site, a quarry near the town of Faxinal do Soturno in the state of Rio Grande do Sul. The rocks where ''Brasilodon'' was found belong to the upp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pseudotherium
''Pseudotherium'' ("false beast") is an extinct genus of mammaliamorph cynodonts from the Late Triassic of Argentina. It contains one species, ''P. argentinus'', which was first described in 2019 from remains found in the La Peña Member of the Ischigualasto Formation in the Ischigualasto-Villa Unión Basin. Discovery and naming The holotype and only known specimen, PVSJ 882, was discovered in 2006 by Argentine palaeontologist Ricardo N. Martínez during an expedition to the Ischigualasto Formation. It consists of a partial skull lacking the lower jaw, quadrate bones and most of the zygomatic arches and premaxillae. The generic epithet ''Pseudotherium'' is derived from the Greek words , meaning "false", and , meaning "beast". The specific name ''argentinus'' references the country of Argentina where it was found. Description ''Pseudotherium'' would have been a relatively large cynodont; excluding its missing premaxillae, the holotype skull is in length. Running along the top of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tritylodontidae
Tritylodontidae ("three-knob teeth", named after the shape of their cheek teeth) is an extinct family of small to medium-sized, highly specialized mammal-like cynodonts, bearing several mammalian traits like erect limbs, endothermy and details of the skeleton. They were the last-known family of the non-mammaliaform synapsids, persisting into the Early Cretaceous. Most tritylodontids are thought to have been herbivorous, feeding on vegetation, such as stems, leaves, and roots, although at least one may have had a more omnivorous diet. Tritylodontid fossils are found in the Americas, South Africa, and Eurasia—they appear to have had an almost global distribution, including Antarctica. Description The skull of tritylodontids had a high sagittal crest. They retained the primitive condition of the joint between the quadrate bone of the skull and the articular bone of the lower jaw—the retention of the joint is one of the reasons they are technically regarded to not be mam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tritylodontid
Tritylodontidae ("three-knob teeth", named after the shape of their cheek teeth) is an extinct family of small to medium-sized, highly specialized mammal-like cynodonts, bearing several mammalian traits like erect limbs, endothermy and details of the skeleton. They were the last-known family of the non-mammaliaform synapsids, persisting into the Early Cretaceous. Most tritylodontids are thought to have been herbivorous, feeding on vegetation, such as stems, leaves, and roots, although at least one may have had a more omnivorous diet. Tritylodontid fossils are found in the Americas, South Africa, and Eurasia—they appear to have had an almost global distribution, including Antarctica. Description The skull of tritylodontids had a high sagittal crest. They retained the primitive condition of the joint between the quadrate bone of the skull and the articular bone of the lower jaw—the retention of the joint is one of the reasons they are technically regarded to not be mammals, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kayentatherium Wellesi
''Kayentatherium'' is an extinct genus of tritylodontid cynodonts that lived during the Early Jurassic. It is one of two tritylodonts from the Kayenta Formation of northern Arizona, United States. ''Kayentatherium'' means "Kayenta Beast", and is named for the geological formation in which it was found, the Kayenta Formation. ''Kayentatherium'' is known from several specimens.Kermack, D. 1982. A new tritylodont from the Kayenta Formation of Arizona. Zoological Journal of the Linnean Society, 76. 1-17.Sues, Hans-Dieter & F. A. Jenkins. 2006. The Postcranial Skeleton of Kayentatherium Wellesi from the Lower Jurassic Kayenta Formation of Arizona and the Phylogenetic Significance of Postcranial Features in Tritylodontid Cynodonts in: Carrano, Matthew T., Gaudin, T. J., Blob, R. W. and Wible, J. R., Amniote Paleobiology: Perspectives on the Evolution of Mammals, Birds, and Reptiles: The University of Chicago Press. pp. 114-152. The specific name honors paleontologist Samuel Welles, who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kayentatherium
''Kayentatherium'' is an extinct genus of tritylodontid cynodonts that lived during the Early Jurassic. It is one of two tritylodonts from the Kayenta Formation of northern Arizona, United States. ''Kayentatherium'' means "Kayenta Beast", and is named for the geological formation in which it was found, the Kayenta Formation. ''Kayentatherium'' is known from several specimens.Kermack, D. 1982. A new tritylodont from the Kayenta Formation of Arizona. Zoological Journal of the Linnean Society, 76. 1-17.Sues, Hans-Dieter & F. A. Jenkins. 2006. The Postcranial Skeleton of Kayentatherium Wellesi from the Lower Jurassic Kayenta Formation of Arizona and the Phylogenetic Significance of Postcranial Features in Tritylodontid Cynodonts in: Carrano, Matthew T., Gaudin, T. J., Blob, R. W. and Wible, J. R., Amniote Paleobiology: Perspectives on the Evolution of Mammals, Birds, and Reptiles: The University of Chicago Press. pp. 114-152. The specific name honors paleontologist Samuel Welles, who ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Adelobasileus
''Adelobasileus'' is a genus of mammaliamorph cynodonts from the Late Triassic (Carnian), about 225 million years ago. It is known only from a partial skull recovered from the Tecovas Formation in western Texas, southern United States, referred to the species ''Adelobasileus cromptoni''. Roughly contemporary with the mammaliaform '' Tikitherium'', ''Adelobasileus'' predates the non-mammalian cynodonts Tritylodontidae and Tritheledontidae by 10 million years. Distinct cranial features, especially the housing of the cochlea, suggest that ''Adelobasileus'' is a transitional form in the character transformation from non-mammaliaform cynodonts to mammaliaforms. For this reason, it is thought to be a close relative of the common ancestor Common descent is a concept in evolutionary biology applicable when one species is the ancestor of two or more species later in time. All living beings are in fact descendants of a unique ancestor commonly referred to as the last universal comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinoconodon
''Sinoconodon'' is an extinct genus of mammaliamorphs that appears in the fossil record of the Lufeng Formation of China in the Sinemurian stage of the Early Jurassic period, about 193 million years ago. While sharing many plesiomorphic traits with other non-mammaliaform cynodonts, it possessed a special, secondarily evolved jaw joint between the dentary and the squamosal bones, which in more derived taxa would replace the primitive tetrapod one between the articular and quadrate bones. The presence of a dentary-squamosal joint is a trait historically used to define mammals. Description This animal had skull of which suggest a presacral body length of and weight about due to the similar parameters to the European hedgehog. ''Sinoconodon'' closely resembled early mammaliaforms like ''Morganucodon'', but it is regarded as more basal, differing substantially from ''Morganucodon'' in its dentition and growth habits. Like most other non-mammalian tetrapods, such as reptiles and amp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tikiodon
''Tikiodon'' is an extinct genus of mammaliamorphs that lived in what is now India during the Late Triassic. Its type and only species is ''Tikiodon cromptoni'', which is known from a single lower postcanine tooth discovered at the Tiki Formation of Madhya Pradesh Madhya Pradesh (, ; meaning 'central province') is a state in central India. Its capital is Bhopal, and the largest city is Indore, with Jabalpur, Ujjain, Gwalior, Sagar, and Rewa being the other major cities. Madhya Pradesh is the seco .... Etymology The generic name ''Tikiodon'' comes from the Tiki Formation, itself named after the nearby village of Tiki, and the Greek word , meaning "tooth". The specific epithet ''cromptoni'' is a reference to South African palaeontologist Alfred W. Crompton. References Prehistoric prozostrodonts Prehistoric cynodont genera Late Triassic synapsids Triassic synapsids of Asia Triassic India Fossils of India Fossil taxa described in 2020 {{Paleo-therap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riograndia
''Riograndia'' is an extinct genus of tritheledontid cynodonts from the Late Triassic of South America. The type and only species is ''Riograndia guaibensis''. Remains have been found in the Caturrita Formation of the geopark of Paleorrota. It was a small non-mammalian cynodont, with several advanced features also present in mammals. Several specimens of ''Riograndia guaibensis'' have been found in the towns of Candelária and Faxinal do Soturno in the Caturrita Formation. The genus defines the ''Riograndia'' Assemblage Zone. Classification ''Riograndia'' is currently classified as a basal genus in the family Tritheledontidae. Other tritheledontids include the related ''Irajatherium'', and two clades, a more basal group including ''Sinoconodon'', ''Brasilitherium'', ''Brasilodon'', and ''Morganucodon'', and a more derived clade of '' Chaliminia'', '' Elliotherium'', ''Pachygenelus'', ''Diarthrognathus'', and ''Tritheledon''. The below cladogram was found by Martinelli and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
