Multituberculate mammals from the Middle Jurassic of Western Siberia, Russia, and the origin of Multituberculata

Tashtykia primaeva gen. et sp. nov. and Tagaria antiqua gen. et sp. nov. (Multituberculata incertae sedis ) are described based on isolated teeth from the Middle Jurassic (Bathonian) Itat Formation from the Berezovsk coal mine in Krasnoyarsk Territory, Western Siberia, Russia. Tashtykia primaeva gen. et sp. nov. is characterized by a P5 with three rows of cusps (cusp formula 2B:4M:6L) and a high sectorial p4 with two triangular lobes, five...