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Tritheledontidae
Tritheledontidae, the tritheledontids or ictidosaurs, is an extinct family of small to medium-sized (about 10 to 20 cm long) cynodonts. They were highly mammal-like, specialized cynodonts, although they still retained a few reptile-like anatomical traits. Tritheledontids were mainly carnivorous or insectivorous, though some species may have developed omnivory. Their skeletons show that they had a close relationship to mammals. Tritheledontids or their closest relatives may have given rise to the mammaliaforms. The tritheledontids were one of the longest lived non-mammalian therapsid lineages, living from the late Triassic to the Jurassic period. Tritheledontids became extinct in the Jurassic period, possibly due to competition with prehistoric mammals such as the eutriconodonts. They are known from finds in South America and South Africa, indicating that they may have lived only on the supercontinent of Gondwana. The family Tritheledontidae was named by South Afr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Riograndia
''Riograndia'' is an extinct genus of prozostrodontian cynodonts from the Late Triassic of Brazil. The type species, type and only species is ''Riograndia guaibensis'', named after the State of Rio Grande do Sul and Guaíba Basin, where it was discovered. 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, Rio Grande do Sul, Candelária and Faxinal do Soturno in the Caturrita Formation. The genus defines the Riograndia Assemblage Zone, ''Riograndia'' Assemblage Zone. Description Holotype (MCN-PV 2264) is an anterior part of a skull, from the tip of snout to the fronto-parietal contact, with complete dentition. The unique feature of ''Riograndia'' are lobed postcanine teeth with approximately equal 5-9 sharp cuspules located along the almost semicircular edge of the c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chaliminia
''Chaliminia'' is an extinct genus of tritheledontid cynodont from the Triassic Period of what is now Argentina. The type and only species is ''C. musteloides''. See also *List of therapsids This list of therapsids is an attempt to create a comprehensive listing of all Genus, genera that have ever been included in the Therapsida excluding mammals and purely vernacular terms. The list includes all commonly accepted genera, but also gene ... References Fossil taxa described in 2007 Triassic Argentina Tritheledontidae {{Synapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachygenelus
''Pachygenelus'' is a genus of extinct cynodont. Fossils have been found from the Karoo basin in South Africa and date back to the Early Jurassic. The genus was named in 1913 on the basis of a partial lower jaw found from South Africa, with the type species being named ''P. monus''. A new species, ''P. milleri'', was named in 1983 and distinguished from the type species in possessing an accessory posterior cusp on the lower postcanines. Description ''Pachygenelus'' had both an articular- quadrate and dentary-squamosal jaw joint characteristic of ictidosaurs. Only mammals possess the dentary-squamosal articulation, while all other tetrapods possess the typical arcticular-quadrate articulation. Thus the jaw of ''Pachygenelus'' can be seen as transitional between non-mammalian synapsids and true mammals. Another feature of ''Pachygenelus'' that is shared with mammals is plesiomorphic prismatic enamel, or enamel arranged into strengthened prisms. The upper and lower tooth rows o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynodont
Cynodontia () is a clade of eutheriodont therapsids that first appeared in the Late Permian (approximately 260 Megaannum, mya), and extensively diversified after the Permian–Triassic extinction event. Mammals are cynodonts, as are their extinct ancestors and close relatives (Mammaliaformes), having evolved from advanced probainognathian cynodonts during the Late Triassic. Non-mammalian cynodonts occupied a variety of ecological niches, both as carnivores and as herbivores. Following the emergence of mammals, most other cynodont lines went extinct, with the last known non-mammaliaform 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, crown-group mammals (notably the therians), all cynodonts probably laid eggs. The temporal fenestrae#Fenestra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jurassic
The Jurassic ( ) is a Geological period, geologic period and System (stratigraphy), stratigraphic system that spanned from the end of the Triassic Period million years ago (Mya) to the beginning of the Cretaceous Period, approximately 143.1 Mya. The Jurassic constitutes the second and middle period of the Mesozoic, Mesozoic Era as well as the eighth period of the Phanerozoic, Phanerozoic Eon and is named after the Jura Mountains, where limestone strata from the period were first identified. The start of the Jurassic was marked by the major Triassic–Jurassic extinction event, associated with the eruption of the Central Atlantic magmatic province, Central Atlantic Magmatic Province (CAMP). The beginning of the Toarcian Age started around 183 million years ago and is marked by the Toarcian Oceanic Anoxic Event, a global episode of Anoxic event, oceanic anoxia, ocean acidification, and elevated global temperatures associated with extinctions, likely caused by the eruption of the Kar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diarthrognathus
''Diarthrognathus'' ("Two joint jaw") is an extinct genus of tritheledontid cynodonts, known from fossil evidence found in South Africa and first described in 1958 by A.W. Crompton.Rieppel, Olivier. Evolutionary Theory and the Creation Controversy', p. 190 (Springer, 2010). The creature lived during the Early Jurassic period, about 200 million years ago. It was carnivorous and small, slightly smaller than ''Thrinaxodon'', which was under long. ''Diarthrognathus'' possesses a jaw structure that is similar to both mammals and more basal synapsids. Its primitive jaw joint is located between the quadrate and articular bones, and its derived, mammalian jaw joint is located between the squamosal and dentary bones. The articular and quadrate bones evolved to become two of the middle-ear bones in mammals.The Mesozoic Era: Age of Dinosaurs', p. 183 (Britannica Educational Publishing, Rosen Publishing Group, 2010). The transition exemplified by ''Diarthrognathus'' suggests that natural ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elliotherium
''Elliotherium'' is an extinct genus of cynodonts which existed in South Africa during the upper Triassic period. The type species is ''Elliotherium kersteni'', named after the Elliot Formation The Elliot Formation is a geological formation and forms part of the Stormberg Group, the uppermost geological group that comprises the greater Karoo Supergroup. Outcrops of the Elliot Formation have been found in the northern Eastern Cape, so ... in which the fossils were found. References Tritheledontidae Late Triassic synapsids of Africa Triassic South Africa Fossils of South Africa Fossil taxa described in 2006 Taxa named by Christian Sidor {{paleo-cynodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Irajatherium
''Irajatherium'' is an extinct genus of cynodonts, known only of the type species ''Irajatherium hernandezi''.Martinelli et al., 2005 It is named in honor of Irajá Damiani Pinto. Species ''Irajatherium hernandezi'' is a species known only by a humerus, a femur, two jaws and an upper arch incomplete, has the upper canine teeth after pills across and the post-mandibular canines with a more developed central cusp, followed by three smaller ones. It was collected in the Candelária Formation in the municipality of Faxinal do Soturno in the Paraná Basin of southeastern Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population .... [...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] |
Tritheledon
''Tritheledon'' is an extinct genus of cynodonts that lived during the Lower Jurassic. Fossils were found in the Elliot Formation, South Africa. Like all cynodonts, it had many traits shared by mammals. Tritheledonts were probably insectivores, and nocturnal Nocturnality is a ethology, behavior in some non-human animals characterized by being active during the night and sleeping during the day. The common adjective is "nocturnal", versus diurnality, diurnal meaning the opposite. Nocturnal creatur ... animals.Luo, Z-X, Z Kielan-Jaworowska & RL Cifelli (2002), In quest for a phylogeny of Mesozoic mammals. ''Acta Palaeontol. Pol''. 47: 1-78. References Further reading * R. Broom. 1912. On a new type of cynodont from the Stormberg. Annals of the South African Museum 7:334-336 Tritheledontidae Early Jurassic synapsids of Africa Jurassic South Africa Fossils of South Africa Fossil taxa described in 1912 {{paleo-cynodont-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Mammal
This is an incomplete list of prehistoric mammals. It does not include extant mammals or recently extinct mammals. For extinct primate species, see: list of fossil primates.Mikko's Phylogeny Archiv Mammaliaformes ' *Genus †''Adelobasileus'' Lucas & Hunt 1990 *Genus †''Bocaconodon'' Montellano, Hopson & Clark 2008 *Genus †''Delsatia'' Sigogneau-Russell & Godefroit 1997 *Genus †'' Tricuspes'' von Huene 1933 *Genus †''Hadrocodium'' Luo, Crompton & Sun 2001 *Genus †'' Fruitafossor'' Luo & Wible 2005 Order † Dinnetheria *Family † Dinnetheriidae Averianov & Lopatin 2011 **Genus †'' Dinnetherium'' Jenkins, Crompton & Downs 1983 Order † Siconodontiformes *Family † Siconodontidae Mills 1971 **Genus †'' Sinoconodon'' Patterson & Olson 1961 Order †Morganucodonta ' *Genus †'' Bridetherium'' Clemens 2011 *Genus †'' Hallautherium'' Clemens 1980 *Genus †''Paceyodon'' Clemens 2011 *Genus †'' Purbeckodon'' Butler et al. 2012 *Genus †'' Rosierodon'' Deb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutriconodont
Eutriconodonta is an order (biology), order of early mammals. Eutriconodonts existed in Asia (including Insular India, pre-contact India), Africa, Europe, North America, North and South America during the Jurassic and the Cretaceous periods. The order was named by Kermack ''et al.'' in 1973 as a replacement name for the paraphyletic Triconodonta. Traditionally seen as the classical Mesozoic small mammalian insectivores, discoveries over the years have shown them to be among the best examples of the diversity of mammals in this time period, including a vast variety of bodyplans, ecological niches and locomotion methods. Classification "Triconodonta" had long been used as the name for an order of early mammals which were close relatives of the ancestors of all present-day mammals, characterized by molar teeth with three main cusps on a crown that were arranged in a row. The group originally included only the family Triconodontidae and taxa that were later assigned to the separate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
