University of Alberta Museums Search

A medium-size (3.4-3.8 cm wingspan) moth with slate-grey and black forewings and sooty-brown hindwings. The forewing ground is black, with paler grey areas at the base, along the costa (especially near the apex area) and in the terminal area. The lower part of the postmedian line is often rusty-red. The stigma is highly variable, usually a thin, silver u or v-shape with a satellite spot distad. The fringe is checkered dark and light grey. The hindwings are dark, sooty brown, shading to a wide blackish terminal band. The antennae are simple and the sexes similar. It is most similar to S. octoscripta, and some specimens need to be determined by examining the genitalia. The end of the valve in interrogationis is sharply angled or pointed (rounded with a preapical spine in octoscripta), and in females of interrogationis the ovipositor lobes are rounded posteriorly (tapered to a narrow apex in octoscripta).

Holoarctic. From Fennoscandia to eastern Siberia. In North America it is found along the northern part of the Boreal forest, from Labrador to Alaska and south in the mountains to Alberta. In Alberta it has been collected in the northern Boreal forest (nr. Ft. McMurray and in the mountains and foothills south to about Banff.