Ostracods from the Lopingian and Permian–Triassic boundary beds at the Gyanyima section in southwestern Tibet, China

Ostracods are reported for the first time in the Late Permian Lopingian to earliest Triassic carbonate sequence in the Ngari region, southwestern Tibet, China. Fifty-three species are recognized, of which 19 are illustrated. One new species (Carinaknightina tibetensis n. sp.) is described and one species is renamed (Bairdia wangi n. nom.). The ostracod fauna as a whole is very similar to those in the Palaeo-Tethys and characteristic of warm water platform deposits. The Early Triassic ostracod assemblages in the section show no substantial difference from the Lopingian assemblages. The palaeoenvironments of the Late Permian and earliest Triassic appear to be open marine with normal salinity and oxygen concentration; there are no indications of anoxic conditions in the Early Triassic in the studied area.