New distributional data on "glacial relict' crustaceans

Earlier reviews on the distribution of the crustaceans Mysis relicta, Pallasea quadrispinosa, Pontoporeia affinis, Gammaracanthus lacustris and Limnocalanus macrurus in Finnish lakes are supplemented with 180 new records, mostly from our field work in 1985-1988. These include records of M. relicta and L. macrurus from Lake Koitere, situated above the highest ancient Baltic shoreline in eastern Finland. The present distribution of G. lacustris, classified as a species in need of monitoring, is reviewed. Some notes on the distribution of these crustaceans outside Finland are also given.