Two New Genera and Two New Species of Pygmephoridae (Acari: Heterostigmata), Rediagnosis of the Genera Diroptes and Sevastianovella, and a Redescription

Two new monotypic genera are described: Pseudositeroptes trachi gen. and sp. n. and Neodiroptes sibiriensis gen. and sp. n. (Acari: Prostigmata: Pygmephoridae), collected under the thin bark of a rotting birch twig lying on the ground in Western Siberia, Russia. A female of Sevastianovella lacidus (Livshits, Mitrofanov and Sharonov) is redescribed based on the type material and a specimen from Western Siberia. The genera Sevastianovella Livshits, Mitrofanov and Sharonov and Diroptes Kaliszewski are rediagnosed. Species Diroptes bohemicus (Mahunka, 1967) comb. n., D. albidus (Livshits et al., 1988) comb. n., D. digitariae (Flechtmann, 1971) comb. n., D. spinisetus (Livshits et al., 1988) comb. n. and D. tauricus (Khaustov and Khaustov, 2022) comb. n. are removed from Sevastianovella. A key to the genera of Pygmephoridae with a 5-segmented leg I in females is provided.