EN
Basing on the newly described (Ectateus ursynowiensis Kamiński sp. nov.) and the type species a new taxonomical hypothesis of the genus Ectateus is proposed. Due to the rules of the International Code of Zoological Nomenclature following changes are made: designation of the lectotype for E. modestus (Fairmaire, 1887) and replacement name for the genus Cosmogaster Koch, 1956.