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''Owenetta'' is an extinct genus of owenettid procolophonian parareptile. Fossils have been found from the Beaufort Group in the Karoo Basin of South Africa. Although most procolophonians lived during the Triassic, ''Owenetta'' existed during the Wuchiapingian and Changhsingian stages of the Late Permian as well as the early Induan stage of the Early Triassic. It is the type genus of the family Owenettidae, and can be distinguished from other related taxa in that the posterior portion of the supratemporal bears a lateral notch and that the pineal foramen is surrounded by a depressed parietal surface on the skull table. ==Species== The type species of ''Owenetta'' is ''O. rubidgei''. It is known from several skulls, but no postcranial skeleton. It was described in 1939 from a partial skull found from the Late Permian Cistecephalus Assemblage Zone of the Beaufort Group.〔Broom, R. (1939). A new type of cotylosaurian, ''Owenetta rubidgei''. ''Annals of the Transvaal Museum'' 19:319–321.〕 Several other localities, all from the overlying Dicynodon Assemblage Zone, have yielded the remainder of the known specimens. The naming of a new species in 2002, ''O. kitchingorum'', extended the temporal range of ''Owenetta'' into the Early Triassic, meaning that the genus had survived past the Permian–Triassic extinction event.〔Reisz, R. R. and Scott, D. (2002). ''Owenetta kitchingorum'', sp. nov., a small parareptile (Procolophonia: Owenettidae) from the Lower Triassic of South Africa. ''Journal of Vertebrate Paleontology'' 22(2):244-256.〕 This new species was considered distinct from the type species based on features found from three nearly complete specimens that were present from the Lystrosaurus Assemblage Zone. Found in 1968, the first material of ''O. kitchingorum'' was a small block containing two skeletons in close proximity to one another (although at the time they were thought to be of the type species).〔Gow, C. E. (1977). ''Owenetta'' in perspective. ''Palaeontologica Africana'' 20:115–118.〕 These skeletons provided much of the information used to distinguish ''O. kitchingorum'' from the type species. ''O. kitchingorum'' differed from ''O. rubidgei'' in that it possessed small postparietals on the posterior edge of the skull table and that the maxilla held no more than 20 teeth, some of which were caniniform. The best preserved specimen seems to be a subadult individual on the basis of features of the skull table. A year after the new species of ''Owenetta'' was named, a paper proposed that it should be assigned to its own distinct genus, although a new name is yet to be provided.〔Modesto, S. P., Damiani, R. J., Neveling, J. and Yates, A. M. (2003). A new Triassic owenettid parareptile and the Mother of Mass Extinctions. ''Journal of Vertebrate Paleontology'' 23(3):715–719.〕 A more recent paper also supported this polyphyly.〔Modesto, S. P. and Damiani, R. (2007). The Procolophonoid Reptile ''Sauropareion anoplus'' from the Lowermost Triassic of South Africa. ''Journal of Vertebrate Paleontology'' 27(2):337-349〕 If this is the case, ''Owenetta'' is once again temporally restricted to the late Permian, and most likely died out at the end of the period as a result of the mass extinction event. Later that year ''Colubrifer'', named in 1982 from a specimen (UCMP 42773) found from the Early Triassic ''Lystrosaurus'' Assemblage Zone and though to represent a short limbed lizard, was re-described. Based on a skull nearly identical to those known of ''Owenetta'', it appears that the animal was a procolophonian almost certainly of that genus. It was found to be a junior synonym of ''Owenetta'', but due to the poor preservation of its holotype, was reassigned ''Owenetta sp''. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Owenetta」の詳細全文を読む スポンサード リンク
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