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Two sections of the Yanshiping Group in the Tanggula Mountains area of the Qinghai-Xizang (Tibet) Plateau, a remote part of western China, have yielded three types of palynomorph assemblages. Two of these clearly indicate that the Xueshan Formation and parts of the diachronous Suowa and Xiali formations were deposited during the early Cretaceous (Berriasian-?Barremian). Largely on negative evidence, because the assemblages are taxonomically impoverished, the rest of the succession is considered to range down into the Upper and possibly Middle Jurassic. The composition of the Cretaceous assemblages suggests that the climate during this period was warm and semi-arid. A Xizang-Tarim Subprovince of the palynofloral North Gondwanan Province is tentatively identified in the north-east Tethyan region. (C) 2004 Elsevier Ltd. All rights reserved.