Chironomus (Chironomus) atritibia Malloch, 1934: 16.
Material examined. Lake Winnipeg light traps: 0.5 km off George Island, 1 male, 13.vii. 1969; Old Fishing Dock, 1 male, 18.viii. 1971; Calder’s Dock, 3 males, 26.viii. 1971.
Of the five males caught in light traps three are intersexes. The normal male has an AR of 4.08, 7 sensilla chaetica on p 2 and 6 on p 3. The male intersexes have female antennae, 38–54 sensilla chaetica on p 2 and 42 (1) sensilla chaetica on p 3.
Distribution and ecology. The species was previously known from New York, Québec, Ontario, Northwest Territories, British Columbia and Washington (Townes 1945: 131, Saether 1970: 7, Saether & McLean 1972: 11, Johnson & Brinkhurst 1971: 1696, Wiederholm 1976: 24, Oliver et al. 1990: 42). Martin (2012) mentions that most specimens listed by Townes (1945), other than the type, probably are C. cucini Webb.
The larva is of the C. salinarius type and characteristic for mesotrophic to moderately oligotrophic lakes (Saether 1975: 3130, Wiederholm 1976: 30). Although no larvae were found in bottom samples from Lake Winnipeg, the species is present in some areas of the northern basin and in the Narrows.