Notodonta torva. Previously treated as N. simplaria Graef. Schintlmeister ([1984]) treated N. simplaria (misspelled as simpliaria in [1984] and in Schintlmeister 2008) as a subspecies of the widespread Eurasian species N. torva, based on similarity of male genitalic structure. In North America N. torva simplaria occurs at least as far north as west-central Northwest Territories and northern Yukon in Canada, so the single Holarctic species concept is plausible, but we also note that few taiga species are truly Holarctic (Mikkola et al. 1991) and more often they represent sibling species. This taxonomic arrangement should be carefully re-examined.