Late Frasnian Atrypida (Brachiopoda) from the South Urals, South Timan and Kuznetsk Basin (Russia)

Basin in Russia (east Laurussian and south Siberian shelf domains in Devonian time) reveal significant geneńc and specific diversĘ in the broadly defined Frasnian-Famen-nian (F-F) bio-crisis time. Eighteen species of aĘpid brachiopods have been recorded, representing 4 subfamilies and 10 genera. The new genus GibberosatrypaMarkovskii & Rzhonsnitskaya, and the new subgenus Spinatrypa (Plicspinatrypa)Rzhonsnitskaya are proposed. Four new species Spinatrypina (Spinatrypina) sosnovkiensis Yudina, Spinar rypa (Plicspinatrypa) rossica Rzhonsnitskaya, Iowatrypa nalivkini Rzhonsnitskaya & Sokiran, and Cartnatina(?) biohermica Yudina are described. The representatives of the Vańatrypinae (including especially conrmon Desquamatia (Desquamatia) alticolifur-mis), Spinatrypinae (Spinatrypina) andAtypinae(Pseudoatrypa,?Costatrypa) arewide-ly distributed in the studied regions. The Pseudogruenewaldtiinae are represented by Iowatrypa artd Pseudogruenewaldtla, of which the first is distributed worldwide, where-as the only undoubted species of the second is resfficted to South Timan, and probably represents a localized latest Frasnian descendant of lowatrypa. The decline phase of aĘpid development was controlled by a variety of environmental factors tied to th