Rheocricotopus (Rheocricotopus) effusus (Walker, 1856)

Adults: Male described by Albu (1968), Lehman (1969), Saether (1985), Makarchenko and Makarchenko (2005), hypopygium in key by Pinder (1978). Female described by Saether (1985).

Immatures: Pupa described by Saether (1985), in key by Langton (1991). Larva described by Cranston (1982), Saether (1985), and in key by Epler (2001).

Ecology and Habitat: Larvae mainly inhabit springs (Thienemann 1954).

NE: Canada (Alberta, Northwest Territories); USA (Illinois, North Carolina, South Carolina, South Dakota). Widespread in the Palearctic.