Siberian mites of the genus Zerconopsis Hull, 1918 (Mesostigmata, Ascidae): description of a new species, re-description of Z. michaeli Evans & Hyatt, 1960, and key for species identification

A new soil-dwelling mite species, Zerconopsis sibiricus sp. nov., is described from Russia based on the females, males, and nymphs. It occurs in plain and mountain areas of Siberia and the Far East (27 localities), in tundra (Low Arctic) and taiga landscapes, including the area of the Cold Pole of the Northern Hemisphere. Another species, Zerconopsis michaeli Evans & Hyatt, 1960, is first reported from Denmark, Russia, Georgia, Turkey, Azerbaijan, and California, USA (23 new records). Its male, nymphs, and larva are first described, and the female description is corrected with illustrations. The range of Z. michaeli in the Old World can be considered as an Amphi-Palaearctic one, excluding areas with very cold and/or continental climates. This species dwells in forest litter, rotten wood, and bracket fungi; however, in Northern Europe almost all records are from arboreal (woody, fungal) habitats. The genus Zerconopsis Hull, 1918 now includes 19 described species from all continents except Africa and Antarctiсa. A revised generic diagnosis is provided, and three morpho-ecological species groups are recognised. A key for the five Zerconopsis species residing in Siberia is given.