The karyotype and morphology of Chironomus brevidentatus sp. n. (Dipt., Chironomidae). A species with a "salinarius type" larva from northern Finland

The karyotype and morphology of Chironomus brevidentatus sp. n. has been de scribed from the Lokka reservoir in northern Finland. The species belongs t o the thummi complex with the chromosome arm combination AB, CD, EF and G. The relationships between the karyotypes of C. brevidentatus, C. major Wulk er & Butler, C. neocorax Wulker and Butler, C. tardus Butler, and "Chironom us sp. 2n = 6, Lokka" are described. The external morphology has been compa red with the suggested nearest relatives or otherwise similar species. The known ecological conditions in the type locality are discussed.