Material examined. CANADA: Manitoba, Lake Winnipeg, Beaver Creek, 1 male, 8.viii. 1969.
Neither this species nor either of the other two species of Tanypus had setae on preepisternum or anepisternum or any sensilla chaetica on metatarsi. No Tanypus immatures were caught in the dredge samples. Most adults were taken in emergence traps near Beaver Creek in 1971.
Distribution. T. concavus was previously known from Ohio, New York and Virginia to Iowa and Texas and possibly Illinois (Roback 1971: 64, 1977: 78; Oliver et al. 1990: 16; Epler 2003; Ashe & O’Connor 2009: 228). The species obviously is rare in Lake Winnipeg.