First record of the late Famennian conodonts in Qamdo, Tibet and their biostratigraphic implications

Abstract

Based on the conodonts recovered for the first time and some brachiopods, this study revises the age of the Wuqingna Formation in eastern Tibet to a late Famennian, challenging prior Carboniferous classification based on coral assemblages. In this study, conodonts are described for the first time from the Wuqingna Formation on the Wuqingka Mountain near Toba Town, Qamdo City in eastern Tibet. The conodont assemblage contains 6 species/subspecies (including morphotypes within open nomenclature) that belong to three genera. The conodont species Polygnathus cf. perplexus, Po. homoirregularis, Po. wuqingnaensis n. sp. and Scaphignathus peterseni suggest an age of late Famennian, probably the Palmatolepis gracilis manca Zone to the Pa. gr. expansa Zone, for the lower part of the Wuqingna Formation, which was previously assigned to the Carboniferous based on the rugose coral assemblages.