Abstract:

Due to the low number and bad preserved condition of the specimens, the anatomical features of Chaohusaurus have not been described in detail. As a result, there is a controversy about the membership of this genus. Based on some new specimens housed in the Geological Museum of Peking University, there are two styles of the forefins compared with the holotype, with differences in skeleton morphology and the mesopodial ossification. The cluster analysis of those specimens shows that there are two groups. Measurements of the forefins suggests that there are two trendlines, so the conclusion that Chensaurus xiaoxianensis and Chensaurus faciles are junior synonyms of Chaohusaurus geishanensis is not appropriate. There are at least two species of Chaohusaurus in Chaohu. Clarifing the diversity of this genus is of significance to the comparison of the Early Triassic ichthyosaurs in the world and the study of the early evolution of basal ichthyosaurs.

Key words: Chaohusaurus, Early Triassic, Anhui Province

摘要：

由于标本少和保存情况不好等原因, 对巢湖龙(Chaohusaurus)解剖学特征缺少详细描述, 安徽地区巢湖龙的种级分异尚存争议。经过对比研究北京大学地质博物馆馆藏的采自安徽巢湖的鱼龙标本与相关模式标本, 基于骨骼形态及腕骨骨化程度等方面的差异, 将标本分为两类。将研究标本及相关模式标本等进行聚类分析, 结果表明存在两个类群。将前肢骨骼数据作图, 显示存在两条生长序列, 该结果推翻了之前的巢县陈氏龙和小巧陈氏龙均为龟山巢湖龙后出同物异名的结论。据此推断, 巢湖马家山地区的巢湖龙可能存在两个物种。厘清巢湖龙的种间关系有助于全球早三叠世原始鱼龙类的对比研究, 并对探讨鱼龙的早期演化具有十分重要的意义。

关键词: 巢湖龙, 早三叠世, 安徽