摘要
A new species of Tsaidamotherium(Bovidae,Artiodactyla),T.brevirostrum,described here represents only the second discovery of the genus.Tsaidamotherium is a mid-sized late Miocene bovid with an odd-looking plate-like horn-core apparatus so far known only from northwestern China.The holotype of T.brevirostrum is a cranial part of skull from the Liushu Formation(late Miocene)of the Linxia Basin.The new species differs from the type species,T.bohlini,mainly in horn-core morphology,having the frontal horn-cores proper much smaller and less distinctly separated from the plate-shaped posterior portion.Furthermore,the new species has smaller frontal sinuses,but a thicker layer of compact bone beneath the horn-core apparatus as seen in frontal section.A complete skull with a smaller horn-core apparatus is considered to represent a female individual of T.brevirostrum.The facial part of the skull,which is first known for this genus,is very short and high,with a high nasal cavity,strongly retracted nasals,and shortened premaxillae and premolar rows.All this probably suggests that the animal with an enlarged nasal cavity,like the modern Saiga and Budorcas,may have had a special adaptation to the high plateau environment.
A new species of Tsaidamotherium （Bovidae, Artiodactyla）, T. brevirostrum, described here represents only the second dis covery of the genus. Tsaidamotherium is a midsized late Miocene bovid with an oddlooking platelike horncore apparatus so far known only from northwestern China. The holotype of T. brevirostrum is a cranial part of skull from the Liushu Formation （late Miocene） of the Linxia Basin. The new species differs from the type species, T. bohlini, mainly in horncore morphology, having the frontal horncores proper much smaller and less distinctly separated from the plateshaped posterior portion. Fur thermore, the new species has smaller frontal sinuses, but a thicker layer of compact bone beneath the horncore apparatus as seen in frontal section. A complete skull with a smaller horncore apparatus is considered to represent a female individual of T. brevirostrum. The facial part of the skull, which is first known for this genus, is very short and high, with a high nasal cavity, strongly retracted nasals, and shortened premaxillae and premolar rows. All this probably suggests that the animal with an en larged nasal cavity, like the modern Saiga and Budorcas, may have had a special adaptation to the high plateau environment.
基金
supported by Strategic Priority Program of the Chinese Academy of Sciences(Grant No.XDB03020104)
National Basic Research Program of China(Grant No.2012CB821900)
National Natural Science Foundation of China(Grant Nos.41002010 and 40730210)
