Article: First occurrence of footprints of large therapsids from the Upper Permian of European Russia
Mikhail V. Surkov, Michael J. Benton, Richard J. Twitchett, Valentin P. Tverdokhlebov and Andrew J. Newell
Large footprints of terrestrial tetrapods have been found in the Cis-Urals region of European Russia. The footprint horizon is in Late Permian (Changhsingian) deposits of the Vyatkian Gorizont (uppermost Tatarian) approximately 50 m below the local Permian/Triassic boundary. Seventeen randomly orientated footprints were excavated and are referred to the ichnospecies Brontopus giganteus. The footprints were emplaced in a reddish-brown mudstone that was deposited from suspension beneath shallow ponded water in a floodplain environment. They were subsequently cast by the base of the overlying fine-grained sandstone, which was deposited from a sheet-flood event. The footprints were produced by a large therapsid, possibly a dinocephalian, but more probably a dicynodont, and represent the first ichnological record of the Therapsida from the Upper Permian of Russia.