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Tritylodon Langaevus
''Tritylodon'' (Greek for 3 cusped tooth) is an extinct genus of tritylodonts, one of the most advanced group of cynodont therapsids. They lived in the Early Jurassic and possibly Late Triassic periods along with dinosaurs. They also shared many characteristics with mammals, and were once considered mammals because of overall skeleton construction. That was changed due to them retaining the vestigial reptilian jawbones and a different skull structure. Tritylodons are now regarded as non-mammalian synapsids. Characteristics If a living ''Tritylodon'' were to be seen today, it would look a lot like a large rodent. They were about long but there is no certainty about the exact weight. Their method of chewing food, a grinding motion with the bottom teeth sliding against the top teeth, resembled that of rodents as well. The bottom teeth were much like a set of cusps and the top teeth were a set of matching grooves that matched perfectly allowing this motion. There were large inciso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Jurassic
The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-Jurassic extinction event, 201.3 Ma (million years ago), and ends at the start of the Middle Jurassic 174.1 Ma. Certain rocks of marine origin of this age in Europe are called "Lias Group, Lias" and that name was used for the period, as well, in 19th-century geology. In southern Germany rocks of this age are called Black Jurassic. Origin of the name Lias There are two possible origins for the name Lias: the first reason is it was taken by a geologist from an England, English quarryman's dialect pronunciation of the word "layers"; secondly, sloops from north Cornwall, Cornish ports such as Bude would sail across the Bristol Channel to the Vale of Glamorgan to load up with rock from coastal limestone quarries (lias limestone from S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free State (province)
The Free State, known as Orange Free State until the 28th of June 1995 when its name was changed, is a province of South Africa. Its capital is Bloemfontein, which is also South Africa's judicial capital. Its historical origins lie in the Boer republic called the Orange Free State and later Orange Free State Province. History The current borders of the province date from 1994 when the Bantustans were abolished and reincorporated into South Africa. It is also the only one of the four original provinces of South Africa not to undergo border changes, apart from the reincorporation of Bantustans, and its borders date from before the outbreak of the Boer War. Law and government The provincial government consists of a premier, an executive council of ten ministers, and a legislature. The provincial assembly and premier are elected for five-year terms, or until the next national election. Political parties are awarded assembly seats based on the percentage of votes each party receive ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eucynodontia
Eucynodontia ("true dog teeth") is a clade of cynodont therapsids including mammals and most non-mammalian cynodonts. The oldest eucynodonts are known from the Early Triassic and possibly Late Permian. Eucynodontia includes two major subgroups, Cynognathia and Probainognathia. The clade was named in 1982 by Thomas Kemp, who defined it as all cynodonts more derived than ''Thrinaxodon''. In 2001, Hopson and Kitching redefined the clade Eucynodontia as the least inclusive group containing Mammalia and ''Exaeretodon ''Exaeretodon'' is an extinct genus of fairly large, low-slung traversodontid cynodonts from the southern parts of Pangea. Four species are known, from various formations. ''E. argentinus'' is from the Carnian-age (Late Triassic) Cancha de Boch ...''.James A. Hopson and James W. Kitching, 2001, "A Probainognathian Cynodont from South Africa and the Phylogeny of Nonmammalian Cynodonts" pp 5-35 in: PARISH A. JENKINS, JR., MICHAEL D. SHAPIRO, AND TOMASZ OWERKOWICZ, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platycraniellus
''Platycraniellus'' is an extinct genus of non-mammalian cynodonts. It is known from the Early Triassic ''Lystrosaurus'' Assemblage Zone of the Normandien Formation of South Africa. The type and only species is ''P. elegans''. See also * List of therapsids This list of therapsids is an attempt to create a comprehensive listing of all genera that have ever been included in the Therapsida excluding mammals and purely vernacular terms. The list includes all commonly accepted genera, but also genera tha ... References Prehistoric cynodont genera Induan life Early Triassic synapsids of Africa Triassic South Africa Fossils of South Africa Fossil taxa described in 1917 Taxa named by Egbert Cornelis Nicolaas van Hoepen {{Paleo-Therapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thrinaxodon
''Thrinaxodon'' is an extinct genus of cynodonts, most commonly regarded by its species ''T. liorhinus'' which lived in what are now South Africa and Antarctica during the Early Triassic. ''Thrinaxodon'' lived just after the Permian–Triassic mass extinction event, its survival during the extinction may have been due to its burrowing habits. Similar to other therapsids, ''Thrinaxodon'' adopted a semi-sprawling posture, an intermediary form between the sprawling position of basal tetrapods (still observed modern Crocodilia) and the more upright posture present in current mammals.Blob R. 2001. Evolution of hindlimb posture in non-mammalian therapsids: biomechanical tests of paleontological hypotheses. 27(1): 14-38. ''Thrinaxodon'' is prevalent in the fossil record in part because it was one of the few carnivores of its time, and was of a larger size than similar cynodont carnivores. Description ''Thrinaxodon'' was a small synapsid roughly the size of a fox and possibly covered ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Progalesaurus
''Progalesaurus'' is an extinct genus of galesaurid cynodont from the early Triassic. ''Progalesaurus'' is known from a single fossil of the species ''Progalesaurus lootsbergensis'', found in the ''Lystrosaurus'' Assemblage Zone of the Balfour Formation. Close relatives of ''Progalesaurus,'' other galesaurids, include ''Galesaurus'' and '' Cynosaurus''. Galesaurids appeared just before the Permian-Triassic extinction event, and disappeared from the fossil record in the Middle-Triassic. The name “Progalesaurus” is derived from Greek, “pro” meaning before, “gale” meaning weasel or cat, and “saurus” meaning lizard or reptile (Sidor and Smith). The name refers to the relationship ''Progalesaurus'' has to the more derived ''Galesaurus.'' Discovery and history ''Progalesaurus'' was originally discovered by Roger M. H. Smith in 1998. The specimen was found in the Sneeuberg mountains near New Lootsberg Pass in the Karoo Basin of South Africa. ''Progalesaurus'' was fir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galesaurus
''Galesaurus'' (from the Greek roots for 'weasel' and 'lizard') is an extinct genus of carnivorous cynodont therapsid that lived between the Induan and the Olenekian stages of the Early Triassic in what is now South Africa. It was incorrectly classified as a dinosaur by Sir Richard Owen in 1859. Notably, ''Galesaurus'' was mentioned in the first issue of Nature in 1869, where T. H. Huxley erroneously expressed confidence that it would eventually be shown to be a dinosaur. Description The largest ''Galesaurus'' skull discovered is roughly long. Larger remains indicate that an adult ''Galesaurus'' is roughly long. Cynodonts, including ''Galesaurus,'' are believed to have had sprawling postures. Examination of ''Galesaurus'' reveals two distinct morphs, a gracile and a robust morph. The main differences between the two morphs lie in the pectoral and pelvic girdles, as well as subtle differences in the fore and hind limbs. The morphological differences may be due to sexual dimo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynosaurus
''Cynosaurus'' is an extinct genus of cynodonts. Remains have been found from the ''Dicynodon'' Assemblage Zone in South Africa.T. S. Kemp: ''The Origin and Evolution of Mammals'' Oxford University Press, 2005. ''Cynosaurus'' was first described by Richard Owen in 1876 as ''Cynosuchus suppostus''. ''Cynosaurus'' has been found in the late Permian period. Cyno- is derived from the Greek word kyon for dog and –sauros in Greek meaning lizard. Paleoenvironment Fossils of ''Cynosaurus'' have been found in the ''Cistecephalus'' and ''Daptocephalus'' Assemblage Zones, in the Balfour Formation of the Beaufort Group, pertaining to the Karoo Supergroup of South Africa. In the Karoo Basin of South Africa riverbanks would be over flooded creating floodplains that could hold all that water to start soil accumulation.Viglietti et al, 2018 In the lower Balfour Formation, the soil deposits suggest a lacustrine environment with abundant leaf impressions (Viglietti et al., 2018). This sugg ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Epicynodontia
Epicynodontia is a clade of cynodont therapsids that includes most cynodonts, such as galesaurids, thrinaxodontids, and Eucynodontia (including mammals). It was erected as a stem-based taxon by Hopson and Kitching (2001) and defined as the most inclusive clade containing Mammalia and excluding ''Procynosuchus'', a Late Permian genus that is one of the most basal cynodonts. Below is a cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ... from Ruta, Botha-Brink, Mitchell and Benton (2013) showing one hypothesis of cynodont relationships: References Cynodonts Lopingian first appearances Extant Permian first appearances Tetrapod unranked clades Taxa named by James Hopson Taxa named by James Kitching {{Therapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Procynosuchus
''Procynosuchus'' (Greek: "Before dog crocodile") is an extinct genus of cynodonts from the Late Permian. It is considered to be one of the earliest and most basal cynodonts. It was 60 cm (2 ft) long. Remains of ''Procynosuchus'' have been found in Russia, Germany, Zambia and South Africa.T. S. Kemp: ''The Origin and Evolution of Mammals'' Oxford University Press, 2005. Paleobiology As one of the earliest cynodonts, ''Procynosuchus'' has many primitive features, but it also has features that distinguish it from all other early therapsids. Some of these features were interpreted by Kemp (1980) as adaptations for a semi-aquatic lifestyle. For example, the wide zygapophyses of the vertebrae allow for a high degree of lateral flexibility, and ''Procynosuchus'' may have used anguilliform locomotion, or eel-like undulation, to swim through the water. The tail of ''Procynosuchus'' is also unusually long for a cynodont. The long haemal arches would have given the tail a lar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dvinia
''Dvinia'' is an extinct genus of cynodonts found in the Salarevo Formation of Sokolki on the Northern Dvina River near Kotlas in Arkhangelsk Oblast, Russia. It is the only known member of the family Dviniidae. Its fossil remains date from the Late Permian and were found with ''Inostrancevia'', ''Scutosaurus'' and '' Vivaxosaurus''. ''Dvinia'' was a small omnivore possessing a large temporal opening typical of advanced therapsids, with a thin postorbital bar separating the eye from the muscle attachment. As a cynodont, it was closely related to mammals. The dentition consisted of a set of small incisors followed by 2 canines and 10-14 postcanines. See also * List of therapsids This list of therapsids is an attempt to create a comprehensive listing of all genera that have ever been included in the Therapsida excluding mammals and purely vernacular terms. The list includes all commonly accepted genera, but also genera tha ... References Further reading * Patricia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
