浙江和江西二叠/三叠系界线层上下的辐鳍鱼类化石与鱼类的绝灭、复苏和辐射

记述了浙江长兴县煤山剖面、江西修水县四都乡东岭剖面和信丰县铁石口镇铁石口剖面二叠/三叠系界线层上下的辐鳍鱼类6个类别的微体化石,包含2新属2新种,它们是:赵氏浙江鱼(Zhejiangichthys zhaoi gen.et sp.nov.)和小齿葆青鱼(Baoqingichthys microdontus gen.et sp.nov.)。这是包括全球二叠/三叠系界线层型剖面和点位(GSSP)在内的全球二叠/三叠系界线层上下辐鳍鱼类微体化石序列的首次报道。在总结煤山剖面已记述的鱼类大化石和微体化石资料的基础上,分析了长兴煤山剖面二叠纪末鱼类的集群绝灭。绝灭发生得很晚,持续的时间很短,规模也很大,绝灭率高达93%。讨论了华南二叠/三叠系之交大绝灭后鱼类的复苏和辐射,认为鱼类和牙形类一样都是大绝灭后在三叠纪最早复苏的类别,最早复苏的鱼类为裂齿鱼类;鱼类从绝灭期到辐射期仅用了1.3 Ma到4 Ma,从地质时间考虑,大绝灭后鱼类的复苏和辐射是相当快的。华南早三叠世以裂齿鱼类的张氏鱼(Zhangina)和软骨鱼类的弓鲛(Hybodus)为代表的组合替代了晚二叠世以古鳕类的中华扁体鱼(sinoplatysomys)和软骨鱼类的中华尖齿鲨(Sinacrodus)为代表的组合。华南晚二叠世海相地层产出的辐鳍鱼类和软骨鱼类的一些土著属与产于特提斯区三叠纪的一些属非常相近,表明华南下扬子区很可能是后来繁盛于特提斯区的三叠纪鱼类的发源地。

ACTINOPTERYGIAN FISHES FROM THE PERMIAN-TRIASSIC BOUNDARY BEDS IN ZHEJIANG AND JIANGXI PROVINCES, SOUTH CHINA AND FISH MASS EXTINCTION, RECOVERY AND RADIATION

The actinopterygian microfossils dealt with in this paper were collected from the Permian- Triassic boundary beds in Meishan section,Changxing County,Zhejiang Province;Dongling section,Xiushui County and Tieshikou section,Xinfeng County,Jiangxi Province,South China.This is the first report of actinopterygian microfossils at the Meishan section where the GSSP of Permian-Triassic boundary is defined.The fish microfossils comprise actinopterygian tooth type-1,Zhejiangichthys zhaoi gen.et sp.nov.,Baoqingichthys microdontus gen.et sp. nov.,Baoqingichthys sp.,Perleididae gen.et sp.indet,and cf.Caturus. This is the sixth report on the fish sequence study near the Permian-Triassic boundary in South China. The material described herein is housed in the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP),Chinese Academy of Sciences.