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Venyukoviamorpha is an extinct superfamily of anomodont therapsids under the superorder Venyukovoidea. While the exact placement of many genera within the basal anomodonts is contentious, it is generally accepted that the Venyukoviamorpha represent a monophyletic clade.〔Benton, M.J., Shishkin, M.A., and Unwin, D.M., eds. (2000), ''The Age of Dinosaurs in Russia and Mongolia'', Cambridge University Press , 105 ISBN 978-0-521-54582-2.〕 Four genera of small, plant-eating anomodonts make up the Venyukoviamorpha -- ''Venyukovia'', ''Ulemica'', ''Otsheria'', and ''Suminia''. All Venyukoviamorpha remains have been found in western Siberia (located during the Middle to Late Permian in Laurasia, the northern part of the supercontinent Pangea). The Venyukoviamorpha were named for ''Venyukovia'' (in turn, named for that fossil's discoverer, Russian geologist P.N. Venyukov).〔Benton, M.J., Shishkin, M.A., and Unwin, D.M., eds. (2000), ''The Age of Dinosaurs in Russia and Mongolia'', Cambridge University Press , 23-24, ISBN 978-0-521-54582-2.〕 But ''Venyukovia'' is known only from lower jaw fragments of a single individual (other fossil remains originally attributed to ''Venyukovia'' having been reassigned to the later genus, ''Ulemia'').〔Benton, M.J., Shishkin, M.A., and Unwin, D.M., eds. (2000), ''The Age of Dinosaurs in Russia and Mongolia'', Cambridge University Press, 105 ISBN 978-0-521-54582-2, and Ivakhnenko, M. F. (1996). "Primitive anomodonts, venyukoviids, from the Late Permian of Eastern Europe". ''Paleontological Journal'' 30: 575–582.〕 Ulemia 〔Fröbisch, Jörg and Reisz, Robert R. (2011), The postcranial anatomy of ''Suminia getmanovi'' (Synapsida: Anomodontia), the earliest known arboreal tetrapod, ''Zoological Journal of the Linnean Society'', 162: 662.〕 and the poorly preserved ''Otsheria'' 〔Angielczyk, Kenneth D. (2004), Phylogenetic evidence for and implications of a dual origin of propaliny in anomodont therapsids (Synapsida), ''Paleobiology'', 30: 268–296.〕 also lack post-cranial remains. To date, the only preserved Venyukoviamorpha post-cranial remains are associated with the later ''Suminia'' fossil. ''Suminia'' is described as a derived venyukovioid and a sister-taxon of ''Ulemica''.〔Rybczynski, Natalia (2000), "Cranial anatomy and phylogenetic position of Suminia getmanovi, a basal anomodont (Amniota: Therapsida) from the Late Permian of Eastern Europe," ''Zoological Journal of the Linnean Society'' 130 (3): 329–373.〕 A ''Suminia'' fossil (PIN 2212/116) revealed a long-tailed animal by therapsid standards. The comparatively long limbs and phalanges with opposable 'thumbs' led to the suggestion that ''Suminia'' was adapted for grasping tree branches in an arboreal lifestyle.〔Fröbisch, Jörg and Reisz, Robert R. (2009), "The Late Permian herbivore Suminia and the early evolution of arboreality in terrestrial vertebrate ecosystems," ''Proceedings of the Royal Society, Biological Sciences'', 276: 3611–3618.〕 Compared with other therapsids, the Venyukoviamorpha were distinguished by comparatively long tooth rows with large incisors.〔Boonstra, L. D. (1971), "The early therapsids", ''Annals of the South African Museum'', 59: (November 1972, paper first published in December 1971) http://archive.org/stream/annalsofsouth59197172sout/annalsofsouth59197172sout_djvu.txt〕 The arrangement of teeth was complex and varied greatly among members of the Venyukoviamorpha.〔Kemp, Tom S. (2005), ''The Origin and Evolution of Mammals'', Oxford University Press, 39-42, ISBN 978-0-19-850761-1.〕 Incisors were chisel-shaped 〔Benton, M.J., Shishkin, M.A., and Unwin, D.M., eds. (2000), ''The Age of Dinosaurs in Russia and Mongolia'', Cambridge University Press , 105, ISBN 978-0-521-54582-2.〕 or leaf-shaped and serrated.〔Cisneros, Juan Carlos, ''et al'' (2011), "Dental Occlusion in a 260-Million-Year-Old Therapsid with SaberCanines from the Permian of Brazil," ''Science'', 331: 1603.〕 Post-canine teeth could be spatulate (''Otsheria''), bluntly conical (''Venyukovia'') for grinding, or leaf-shaped for shredding (''Suminia'').〔Rybczynski, Natalia (2000), "Cranial anatomy and phylogenetic position of Suminia getmanovi, a basal anomodont (Amniota: Therapsida) from the Late Permian of Eastern Europe," ''Zoological Journal of the Linnean Society'', 130 (3): 329–373.〕 The mixed dentition of ''Suminia'' is claimed to represent the first evidence of the efficient processing of food by chewing.〔Rybczynski, Natalia and Reisz, Robert R. (2001), "Earliest evidence for efficient oral processing in a terrestrial herbivore," ''Nature'' 411: 684–687.〕 The Venyukoviamorpha lived in environments surrounded by amphibians, pareiasaurs and other reptiles, as well as other therapsids. As an example, small plant-eating ''Otsheria'' existed alongside larger therapsid herbivores (''Estemmenosuchus'') and therapsid hunters (biarmosuchians, anteosaurid dinocephalians, and gorgonopsians).〔Kemp, Tom S. (2006), "The origin and early radiation of the therapsid mammal-like reptiles: a palaeobiological hypothesis," ''Journal of Evolutionary Biology'', 19 (4): 1231–1247.〕 ==References== 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「Venyukoviamorpha」の詳細全文を読む スポンサード リンク
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