新疆准噶尔盆地北缘Pliopithecus的发现(英文)

THE DISCOVERY OF PLIOPITHECUS FROM NORTHERN JUNGGAR BASIN,XINJIANG

1997和 1 998年的野外工作期间 ,在新疆准噶尔盆地北缘铁尔斯哈巴合中中新世哈拉玛盖组的底部第二砂层中发现了 4枚上猿牙齿。两枚显然是属于同一个体的左m2和m3发现于 980 1 7地点 ,地理坐标为 46°39.997′N ,88°30 .41 2′E。另一枚左下第一门齿和左上第四前臼齿产自该地点附近的同一砂层中。这是在中国境内、也是亚洲的第二个上猿化石地点。该 4枚牙齿中 ,下门齿可能与m2、m3属同一个种。m2刚开始经受磨蚀 ,m3则刚萌出齿槽。它们不同于所有已知种 (P .zhanxiangi、P .vindobonensis、P .antiquus、P .platyodon和P .priensis)的最明显的特征是在唇侧有一个很深的、间于下原尖和下次尖的漏斗状小坑。该坑由前次脊 (prehypocristid)、下次尖前方的斜脊的唇侧分支和沿下原尖唇侧壁向下延伸的一条脊所围成。此外 ,m3稍短于m2。在其他形态特征方面 ,新疆的种又以m2和m3尺寸较小、齿尖较低、齿脊较锐、近中凹和远中凹发育、釉面褶皱和唇侧齿带很发育而不同于我国宁夏同心的Pliopithecuszhanxiangi;以m2和m3的冠面较短宽且有很发育的上猿三角与P .vindobonensis区分 ;其m2和m3的尺寸明显大于P .antiquus。但在尺寸和其他形态上与P .platyodon很相似。铁尔斯哈巴合的m2、m3和下门齿应代表上猿属内的一个新?

A new species of Pliopithecus- P. bii sp. nov., is erected on dental morphology of m2～m3 and a central lower incisor, which were collected from the early Middle Miocene Halamagai Formation of Tieersihabahe in the northern Junggar Basin of Xinjiang Uygur Autonomous Region, China. The new species is especially characterized by a deep buccal funnel, which is enclosed by the cristid obliqua, the crest descending along the buccal slope of protoconid, and the buccal branch of prehypocristid. One P4 collected from near the same locality is assigned to Pliopithecus sp. because of its smaller size in relation to the m2and m3. The associated mammal fauna of P. bii is approximately comparable to Tongxin fauna. Consequently P. bii is of early Middle Miocene in age, equivalent to the European Neogene land mammal age MN6. The high similarity between Dionysopithecus shuangouensis and Pliopithecus especially P. bii supports the inference made by Harrison and Gu(1999) that pliopithecini (Pliopithecus) was derived from an Asian rather than an African source.