Trichoptera hydroptilidae (Insecta) from Soviet Union Far-Eastern territories

This is a contribution to the study of the scarcely known Trichoptera Hydroptilidae from Soviet Far-East (Primorye, Amur River basin, Kuril Islands, Kamtschatka, Chukotka). The discovery of a new species of Stactobia McL. on Kunashir Island, very far from the known distribution area of the genus, was quite unexpected. Agraylea multipunctata Curt., 1834, and A. cognatella McL., 1880, certainly are distinct species, both present in the Soviet Far-East, but apparently not sympatrically. Oxyethira ecornuta Morton, 1893, previously known from Fennoscandia and from eastern Canada, is redescribed from Primorye. Orthotrichia tragetti Mosely, 1830, with eastern-most known localities in Ukraina and Finland, is another surprising discovery for Primorye.