贵州兴义三叠纪海生爬行动物群的地层分布及其生物多样性  

BIODIVERSITY AND STRATIGRAPHIC DISTRIBUTION OF THE TRIASSIC XINGYI MARINE REPTILE FAUNA, GUIZHOU PROVINCE

作　　者：马乐天[1] 季承[1,2] 孙作玉[1] 杨鹏飞[1] 邹晓东[1] 

机构地区：[1]北京大学地质系和地质博物馆,北京100871 [2]中国科学院南京地质古生物研究所,江苏南京210008

出　　处：《地层学杂志》2013年第2期178-185,共8页Journal of Stratigraphy

基　　金：国家自然科学基金项目(No.40920124002;40672002;40302009)资助

摘　　要：根据在贵州省兴义市乌沙镇开展的以自然层为精度的大规模化石科学发掘工作,对那里保存精美、属种丰富、分异度高的三叠纪海生爬行动物群———兴义动物群有新发现:1)根据海生爬行动物化石产出情况,可将化石层分为下、中、上三段:26～35层为下段,厚1.41m,主要以产出大量贵州龙为特点;36～44层为中段,厚2.11m,鳍龙类和鱼龙类均有出现;45～53层为上段,厚1.88m,以产出保存完整的鱼龙和海龙为特点,伴生大量海百合。2)从兴义动物群海生爬行动物组成面貌来看,化石层下段产出的鳍龙类分子,包括幻龙、鸥龙和大量贵州龙,进一步印证了其西特提斯亲缘性;而化石层上段发现完整贵州鱼龙、黔鱼龙及海龙材料,与贵州晚三叠世卡尼期关岭动物群组成面貌有相似之处。Recent excavation in the Wusha area, Xingyi, Guizhou Province, reveals new discoveries of the Triassic Xingyi Biota： 1） The fossiliferous strata can be subdivided into three reptile beds. The Lower Reptile Bed is composed of layers 26-35 and is 1.41 m in thickness, characterized by the abundance of Keichousaurus. The Middle Bed consists of layers 36-44 and is 2.11 m thick, containing both sauroptery- gians and ichthyosaurs. The Upper Reptile Bed includes the layers 45 -53, and its the thickness is 1.88 m. The characteristic taxa in this bed are well-preserved ichthyosaurs, thalattosaurs and crinoids. 2） The occurrence of sauropterygians in the Lower Bed, including Nothosaurus, Lariosaurus and Keichousaurus, shows a close affinity with the western Tethys, while the occurrence of complete Qianichthyosaurus, Guizhouichthyosaurus and thalattosaurs in the Upper Bed indicates a close relationship with the Guanling Biota.

关 键 词：生物地层 兴义动物群 海生爬行动物 法郎组 三叠纪 兴义 贵州省 

分 类 号：P534.51[天文地球—古生物学与地层学]