A new species of Achenium Leach, 1819 from Taman peninsula with the key to the Russian fauna of the genus (Coleoptera: Staphylinidae: Paederinae)

Achenium volcanus sp. n. found in the ground at the Karabetova hill chain of Taman Peninsula is described. Presumably the new species belongs to the Achenium caucasicum species group of Assing and reliably differs from the closely related species in the structure of the aedeagus. Among species of Achenium that may occur sympatrically, it is distinguished by the structure of the aedeagus and smaller body size. To facilitate local studies of Achenium the key to species of this genus that are known from, or presumed to occur in Russia is provided