Permian neogondolellids from south China: significance for evolution of the serrata and carinata groups in North America

Abstract

TheNeogondolella serrata(Clark and Ethington) group was originally reported as a North American provincial conodont lineage. More or less complete Permian sequences now recognized in China include species originally thought to be part of the North American provincial fauna as well as species reported previously from other parts of the world. Comparison of Chinese and North American species may be useful in correlation of series and stage boundaries between the two areas. The Chinese conodont succession demonstrates that most Permian neogondolellids were not provincial but attained worldwide distribution. Late Permian ancestors of Early TriassicNeogondolellaspecies were apparently widespread in the Tethyan Sea and the sudden appearance of TriassicNeogondolellaspecies in North America without Permian ancestors is only the consequence of the absence of the latest Permian marine rocks in North America.Of particular regional stratigraphic interest is the occurrence of the North American speciesN. wilcoxiClark and Behnken in the Chinese late Guadalupian-Dzhulfian. This occurrence supports a late Guadalupian (post-Lamar) age for the uppermost Gerster Formation in Utah.