海龙类化石在云南泸西上三叠统的发现

采自云南泸西县城附近小兴安村晚三叠世卡尼期小凹组的海龙化石,是关岭生物群海龙类化石在贵州关岭之外地区的首次发现。该化石标本共保存有9枚较好的背椎骨,21条完好的肋骨及若干腹肋。靠近头部的4枚背椎骨为有次序的自然排列。背椎椎体长约12cm,椎体横突发育,椎体腹侧轻微凹入,呈双凹形,近似圆形。这一特征与鱼龙类脊椎骨明显的双凹特征有所区别,故暂且将其归于海龙类。新采集的该化石标本为探讨海龙类的古地理分布,以及寻找规律生物群新化石产地提供了信息。

The discovery of Thalattosauria (Reptilia:Diapsida) from the Late Triassic strata of Luxi County,Yunnan Province

This paper reposts a thalattosaur specimen collected from the Late Triassic Xiaowa Formation in Xiaoxingan Village, Luxi County, Yunnan Province.It is the first record of Thalattosauria fossil outside Guanling, Guizhou Province.The specimen consists of 9 well preserved dorsal vertebrae, 21 dorsal ribs, and several gastralia.4 dorsal vertebrae are present and arranged as a sequence of natu-ral order.The length of dorsal vertebrae is about 12cm.The transverse process is well developed.The two ends of the dorsal verte-brae are slightly biconcave, distinctly different from ichthyosauria vertebrae with obvious biconcave.The specimen is tentatively as-signed to the Thalattosauria.The new discovery provides new information for paleobiographic distribution of the Thalattosauria and the search for new fossil localities of the Guangling biota.