First records of Wuchiapingian (Late Permian) conodonts in the Xainza area, Lhasa Block, Tibet, and their palaeobiogeographic implications

Yuan, D.X., Zhang, Y.C., Zhang, Y.J., Zhu, T.X. & Shen, S.Z., 2014. First records of Wuchiapingian (Late Permian) conodonts in the Xainza area, Lhasa Block, Tibet, and their palaeobiogeographic implications. Alcheringa 38, 546-556. ISSN 0311-5518.Conodonts are among the best fossil groups to provide high-resolution biostratigraphic correlation and resolve the palaeobiogeographic evolution of the Permian. However, they have been rarely reported from the Lhasa Block in Tibet. Here we report the first discovery of Wuchiapingian (early Lopingian) conodonts from the Xiala Formation in the Lhasa Block, Tibet. This conodont fauna includes two genera and three species (Clarkina liangshanensis, C. orientalis, Iranognathus sp.). The conodont fauna indicates that the Xiala Formation previously assigned to the Guadalupian actually ranges from late Kungurian to late Wuchiapingian. The existence of the late Wuchiapingian conodont species Clarkina orientalis and C. liangshanensis in the Lhasa Block provides additional data to support the viewpoint that this block probably had been in a warm-water regime during the Wuchiapingian (Lopingian).