Trichopalpus nigribasis Curran, 1927: 255. HOLOTYPE: J, Canada,Alta.[= Alberta], Banff, 23.viii.1922, No. 2606, C. B. G. Garrett leg. (CNC).
Chaetosa pilirostris Ringdahl, 1936: 178. HOLOTYPE: J, Norway, ‘im nördlichen Norwegen [= in northern Norway], Ein J vom Verf. bei Tromsö [= one male collected by the author near Tromsø]’ (probably MZLU). Synonymized by GORODKOV (1986: 28).
Distribution. Finland (HACKMAN 1980: 131); Norway (NELSON & GREVE 2002: 46); Nearctic region (VOCKEROTH 1965: 836).