A medium-diversity fauna of late Ordovician rhynchonelliformean brachiopods occurs in the Tauken Formation (upper Caradoc-lowermost Ashgill) of north Central Kazakhstan. It demonstrates close similarity to the approximately contemporaneous faunas characteristic of shallow clastic shelves (BA 2-3) of the Chingiz and Chu-Ili ranges (both in Kazakhstan) and South China, but is characterized by a high proportion of endemic new species, including Tetraphalerella bestiubensis sp. nov., Glyptomena kaskolica sp. nov., Dinorthis taukensis sp. nov., Rhynchotrema seletensis sp. nov., and Nalivkinia (Pronalivkinia) zvontsovi sp. nov. The abundance of Rhynchotrema is somewhat unusual by comparison with faunas from other Kazakhstanian terranes, where rhynchonellides of the family Ancistrorhynchidae are usually dominant in near-shore biofacies. The occurrence of the atrypides Sulcatospira and early Nalivkinia demonstrates a clear biogeographical linkage with approximately contemporaneous faunas of South China.

Key words: Brachiopoda, Upper Ordovician, taxonomy, biogeography, Kazakhstan.

Igor F. Nikitin [oigronina@nursat.kz], Institute of Geological Sciences, Kabanbai−Batyr st. 69a, Almaty 480100, Kazakhstan; Leonid E. Popov [Leonid.Popov@nmgw.ac.uk] and Michael G. Bassett [Mike.Bassett@nmgw.ac.uk], Department of Geology, National Museum of Wales, Cathays Park, Cardiff CF10 3NP, Wales, U.K.