|scientific name Catocala briseis Wlk.|
common name Briseis Underwing, Ribbed Underwing
Mature hardwood and mixedwood forest, and in particular aspen forest.
Adults are on the wing from the end of July through late September.
A large (5.9-6.5 cm wingspan) moth with dark blackish forewings and deep red-orange hindwings. The forewings are dark grey with a few patches of pale scales, in particular before and below the reniform and along the subterminal line. There is a diffuse band or patch of paler scales, some of which are brown, inside of the subterminal band. The hindwings are deep red-orange, crossed by a complete black median and a wider black terminal band. The hindwing fringe is white. The antennae are simple, and the sexes are similar. The contrasting pale patch and brown scaling on the outer half of the forewings is diagnostic of briseis.
Adults are nocturnal and come to light, but they are best collected using sugar baits. They emerge in late summer and early fall and produce the eggs which overwinter. The larvae are solitary defoliators.
A common, widespread insect. No concerns.
No Alberta data. Elsewhere the larvae have been reported to feed on poplars (Populus) and willows (Salix). There is some evidence to suggest that willow may be a preferred hostplant.
Across the Boreal forest region from Newfoundland to the Pacific, south to Massachusetts and Pennsylvania. In the west, replaced southward in the mountains by the similar but larger C. groteiana. In Alberta, it is one of the most common and widespread Catocala species. Occurs across the Aspen parkland and Boreal forest region, north almost to Lake Athabasca. It is also found in lower elevations of the mountains, the Cypress Hills and wooded parts of the Grasslands region.
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