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描述了牛科小羚羊(Dorcadorys Teilhard et Trassaert,1938)一新种:D.orientalis sp. nov.。材料发现于陕西蓝田Loc.6,晚中新世灞河组中部。它和属型种Dorcadoryx triquetricor- nis的主要不同在于它的角心长,向上分散度大,角后窝深而狭长,眼眶向头骨两侧突出不明显,下颌骨水平支低而纤细,颊齿窄和前臼齿列相对长等。Dorcadoryx是中国北方和蒙古地区晚中新世至早上新世的特有类型之一。我国山西晚中新世的?Tragoreas(Bohlin,1935)、蒙古新近纪晚期的Tragoreas sp.2和sp.3以及Olonbulukia(?)sp.(Dmitrieva,1977)可能是它的成员。经修订,属的主要特征是个体小至中等大小,头骨狭长,角基之间的额面不向上隆起,头骨弯曲发生在额顶骨之间,眶上孔小,眶前窝大,颅顶部狭长,基枕部具中沟,前结节不明显,角心位于眼眶之上、不旋转,内外侧扁,分散度不大,稍向后弯曲,角柄长,角后窝存在, 前臼齿列退化以及p4的下后尖和下前尖相连等。它可能属于山羊亚科,包含4—5种。新种可能是其中的一个早期类型。
A new species of Dorcadorys Teilhard et Trassaert (1938) is described: D. orientalis sp. Nov. The material was found in Loc.6, Lantian, Shaanxi, central part of Late Miocene Bahehe Formation. The main difference between it and the genus Dorcadoryx triquetricoris lies in its angle of heart and heart, upward dispersion, deep and narrow posterior fossa, orbital protrusion to both sides of the skull is not obvious, the mandibular horizontal branch is low and slender, cheek teeth Narrow and premolar dentition relatively long and so on. Dorcadoryx is one of the peculiar types of Late Miocene to Early Pliocene in northern China and Mongolia. Tragoreas (Bohlin, 1935), late Neocene in Shanxi Province of China, Tragoreas sp.2 and sp.3 in late Neocene, and Olonbulukia sp. (Dmitrieva, 1977) may be its members. Revised, the main characteristics of the genus is small to medium size, the skull is long and narrow, the forehead between the horn does not rise up, the skull bending occurred between the frontal bone, supraorbital foramen, orbital fossa, the top of the slender , The base pillow with a groove in the ditch, the anterior nodule is not obvious, the angle of the heart is located above the orbit, does not rotate, the inside and outside the flat, decentralized, slightly bent back, long shank, angle posterior fossa, premolar dentition degeneration As well as the lower posterior and lower posterior apex of p4. It may belong to goats subfamily, contains 4-5 species. The new species may be one of the early types.