辽西地区义县组昆虫化石及其生物地层、古生态学意义

作为热河昆虫群的重要组成部分,辽西地区义县组昆虫化石内容独特、丰富,共有49科83属,明显区别于同属热河昆虫群的大北沟组和九佛堂组,生物地层单位称为Epheeropsis trisetalis-Sinaeschnidia cancellosa组合,时代为晚侏罗世晚期-早白垩世早期.昆虫群反映了当时温暖而潮湿的气候环境及因地形不同引起的小气候的存在.

FOSSIL INSECTS FROM YIXIAN FORMATION IN WESTERN LIAONING, CHINA: Biostratigraphical and paleoecological significances

Various unique fossil insects,including 83 genera of 49 families,which are the most important members of the Jehol Entomofaunae,have been collected from Yixian Formation in western Liaoning Province,China.Biostratigraphically,the fossil insects are represented by the Ephemeropsis trisetalis-Sinaeschnidia cancellosa Assembalge,whose age is defined as the late Late Jurassic-early Early Cretaceous and obviously different from that of the Jiufotang Formation and Dabeigou Formation which are also assigned to the Jehol Entomofaunae in Northern Hebei and Western Liaoning.These sawflies can provide information about a warm and humid environment and indicate that different microclimates existed at the time,probably caused by topographic differences.