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''Maleevus'' is a genus of herbivorous ankylosaurid dinosaur from the late Cretaceous, around 90 million years ago, of Mongolia. Between 1946 and 1949, Soviet-Mongolian expeditions uncovered fossils at Shiregin Gashun. In 1952, Soviet palaeontologist Evgenii Aleksandrovich Maleev named some ankylosaurian bone fragments as a new species of ''Syrmosaurus'': ''Syrmosaurus disparoserratus''. The specific name refers to the unequal serrations on the teeth.〔Maleev E.A., 1952, "Новый анқилосавр из вернего мела Монголии", ''Doklady Akademii Nauk, SSSR'' 87: 273-276〕 The holotype, PIN 554/I, was found in a layer of the Bayan Shireh Formation dating from the Cenomanian-Santonian. It consists of two upper jawbones, left and right maxillae. Maleev erroneously assumed these represented the lower jaws. Referred was specimen PIN 554/2-1, the rear of the skull of another individual.〔 In 1977, Teresa Maryańska noted a similarity with another Mongolian ankylosaur, ''Talarurus'', in that both taxa have separate openings for the ninth to twelfth cerebral nerve; she therefore renamed the species as ''Talarurus disparoserratus''.〔T. Maryańska, 1977, "Ankylosauridae (Dinosauria) from Mongolia", ''Palaeontologia Polonica'' 37: 85-151〕 Having determined that ''Syrmosaurus'' is a junior synonym of ''Pinacosaurus'', Soviet palaeontologist Tatyana Tumanova named the material as a new genus ''Maleevus'' in honor of Maleev in 1987. The type species remains ''Syrmosaurus disparoserratus'', the ''combinatio nova'' is ''Maleevus disparoserratus''.〔T.A. Tumanova, 1987, "Pantsirnyye dinozavry Mongolii", ''Trudy Sovmestnaya Sovetsko-Mongol'skaya Paleontologicheskaya Ekspeditsiya'' 32: 1-80〕 In 1991, George Olshevsky named the species as a ''Pinacosaurus disparoserratus''.〔Olshevsky, G., 1991, ''A revision of the parainfraclass Archosauria Cope, 1869, excluding the advanced Crocodylia''. Mesozoic Meanderings 2, 196 pp〕 In 2014, Victoria Megan Arbour determined that the rear skull was not different from that of many other ankylosaurids and that the single distinguishing trait of the teeth, a zigzag pattern on the ''cingulum'', was shared with ''Pinacosaurus''. She concluded that ''Maleevus'' was a ''nomen dubium''.〔Arbour, Victoria Megan, 2014, ''Systematics, evolution, and biogeography of the ankylosaurid dinosaurs''. Ph.D thesis, University of Alberta〕 The preserved maxillae have length of about twelve centimetres. This indicates that ''Maleevus'' was a medium-sized ankylosaur. ''Syrmosaurus disparoserratus'' was by Maleev placed in the Syrmosauridae.〔 Today it is seen as a member of the Ankylosauridae. ==See also== * Timeline of ankylosaur research 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「Maleevus」の詳細全文を読む スポンサード リンク
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