Conodonts from the Lower Griesbachian Otoceras Latilobatum Bed of Selong, Tibet and the Position of the Permian—Triassic Boundary

Abstract

Abstract The conodont fauna from the Lower Griesbachian Otoceras latilobatum bed at Selong, Tibet comprises Hindeodus typicalis, Isarcicella? parva, Neogondolella aff. N. carinata, N. aff. N. changxingensis, N. taylorae n. sp., and N. tulongensis. A single Isarcicella isarcica is reported from the top of the bed. Concurrent appearance of Isarcicella? parva and Otoceras is confirmed. The Selong conodont fauna of the Otoceras latilobatum bed differs from that of the uppermost Permian Changhsingian and Dorashamian stages. Earlier reports of uppermost Permian conodonts in the Griesbachian, and of Griesbachian conodonts in the uppermost Permian are refuted or remain unverified. Taxonomic revision of many of the Neogondolella species from the P—T boundary interval is given, including the description of lowermost Triassic N. taylorae n. sp. and uppermost Permian N. n. sp. A.