The systematic position of the genus Derops Sharp, 1889 (several species in the Palaearctic and Oriental regions) within the family Staphylinidae and its relationship to the genus Rimulincola Sanderson, 1947 (one species in the eastern Nearctic region) are discussed. The genus Derops is shown to be congeneric with Rimulincola, which becomes a junior synonym of Derops. — The genus Derops is removed from the subfamily Phloecharinae and reassigned to the subfamily Tachyporinae as a separate new tribe Deropsini. A key to the tribes of Tachyporinae is given. — Derops kasugaensis (Sawada, 1956) is placed in synonymy with Derops longicornis Sharp, 1889. The published data on the ecology of species of Derops are summarized and detailed ecological observations by the author on D. divalis (southern Illinois) andD. longicornis (Japan, Honshu) are given and compared. The disjunct (eastern and/or midwestern North America-southeastern Asia) type of geographical distribution of Derops is discussed and compared with similar distributions of the syrphid genus Pterallastes Loew (Diptera and some plant genera). This distribution pattern is considered to be unique within the order Coleoptera.