Mid Ordovician (Darriwilian) brachiopods of South Kazakhstan

Mid Ordovician (early Darriwilian) brachiopod faunas from the Chu-Ili Range and the West Balkhash region of South Kazakhstan are revised and described systematically. They include 21 species of linguliformean and 43 species of rhynchonelliformean brachiopods ascribed to 60 genera, of which Akadyria, Asperdelia, Bekella, Kopalina, Kopella, Kujanorthis, Oxostrophomena, Tenuimena, Turanorthis and Uzunbulakia are new. Other new taxa are the subgenus Yangtzeella (Vadimella) and the species Akadyria simplex, Archaeorthis major, Asperdelia villosa, Bekella paula, Camerella mica, Hesperonomia? uzunbulakensis, Kopalina perplexa, Kopella incerta, Kujanorthis anderkensis, Leptella sarytumensis, Metacamarella kopalica, Neostrophia marinae, Taphrodonta kelleri, Taphrodonta rukavishnikovae, Tenuimena planissima, Toquimia margiata, Torynelasma zhetysuicum, Trematorthis karasaiensis, Turanorthis kujandensis, Tuvinia alakulica, T. fasciculata, Uzunbulakia rugosa, Westonia? anrakhaica and Yangtzeella (Vadimella) igori. These faunas show strong biofacies differentiation and at least five environmentally controlled associations can be recognised. The early Darriwilian.