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描述了产自内蒙古高特格上新世地层中的三趾马属化石,分别归入两个种。下部层位的材料因吻部间颌突较高、犬齿粗壮并在其内侧前后缘形成嵴和沟、下颊齿齿冠较低、双叶较圆以及外中谷很深等特征而归入意外(笨重)三趾马(Hipparion(Baryhipparion)insperatum Qiuet al.,1987),其古地磁年龄为4.3Ma;上部层位的标本因下颊齿高冠、双叶贺风型、外中谷宽浅以及下马刺发育等特征而归入黄河(近)三趾马(H.(Plesiohipparion)huangheense Qiu etal.,1987),其年龄约为3.9 Ma。在此之前,这两种三趾马的分布局限,仅发现于山西榆社和陕西蒲城的上新世地层,高特格新材料的发现增加了人们对于其地理和地史分布以及特征演化的了解。此外,还对高特格颊齿标本进行了连续横切,结果显示,随着年龄增加H.insperatum的双叶一直较圆,下后尖逐渐大于下后附尖,但外中谷形态并不随磨蚀加深而有大的改变;H.huangheense的双叶稳定、贺风型,外中谷内端随着磨蚀的加深变得宽圆,下马刺渐弱而下反马刺逐渐显现,下内尖逐渐变得圆钝,其后的凹也逐渐变小。高特格地点相对较低齿冠的H.insperatum向极高齿冠的H.huangheense的转变,指示了内蒙古中部地区在上新世逐步干旱化和草原化的过程。
The fossils of the genus Triphaeria originating from the Pliocene of the Gotech Formation in Inner Mongolia are described, belonging to two species. The material of the lower layer was classified as having a high kyphosis between kyphoses, thick canine teeth and the formation of ridges and valleys on the anteromedial and posterior edges, lower cheek tooth crowns, more bilobal leaves and deep outer valleys (Clumsy) Hipparion (Baryhipparion) insperatum Qiu et al., 1987), with an ancient paleomagnetic age of 4.3Ma; (Plesiohipparion) huangheense Qiu et al., 1987), with an age of about 3.9 Ma. Prior to this, the distribution of these two three-toed horses was only found in the Pliocene strata of Yushe, Shanxi Province and Pucheng, Shaanxi Province. The discovery of Goggles new materials has increased the distribution of geography and geostrategy and the evolution of features Understand. In addition, continuous transversal transection was performed on high-Tegel buccal teeth specimens. The results showed that the bilobal leaves of H. insperatum were more rounded with age, and the posterior apex was gradually larger than the posterior apical, but the outer mid-valleys were not ablated Deepening and big changes; H. bangheense bilobal stability, He wind type, outside the valley in the deepening of the deepening with the deepening of the abrasion, the lower spur fading anti spurs appear gradually, the next tip gradually becomes Obtuse, followed by the concave gradually smaller. The shift from H. insperatum with its relatively low crown to H.huangheense with a very high crown indicates the process of aridification and steppeping in the central part of Inner Mongolia during the Pliocene.