A late Changhsingian bivalve complex including species from the genera Palaeonucula, Dacryomya, Malletia ?, Sarepta ?, Myalina, Pteria, Maitaia, and Unionites is discovered in northeastern Asia for the first time. The transition from the Permian to the Triassic in high-boreal basins has been shown to include two extinction episodes similar to those observed in the low-boreal basins and apparently evoked by trap volcanism activation in Siberia. Changes in benthic foraminifera diversity and vertical distribution of ammonoidea of the genus Otoceras in transitional Permian-Triassic deposits also are considered. Images of bivalves from the most typical taxa are presented.
