Size
wingspan 34-41 mm; female larger than male
Identification
Adult: forewing mottled light and dark brownish-gray, with the lighter area forming a large irregular gray stripe angling from base of wing to inner margin, then diagonally to apex; median and subterminal areas darker gray, mixed with paler blotches; hindwing brownish-gray, unmarked; fringes on all wings checkered; antennae in both sexes very small, hair-like
Range
eastern two-thirds of Canada and northeastern United States: Newfoundland to Alberta, south to Minnesota and New England, and in the Appalachians to Tennessee and North Carolina
Habitat
coniferous and mixed forests; adults are nocturnal and occasionally come to light
Season
adults fly from May to July
Food
larvae feed on the roots of trees, including seedlings, of primarily Balsam Fir (Abies balsamea) and Red Spruce (Picea rubens); also reported to feed on roots of White Spruce (Picea glauca), birch (Betula spp.), Trembling Aspen (Populus tremuloides), and ferns (Dryopteris spp. and Athyrium filix-femina)
Remarks
The sex pheromone of this species is released from the female's hindwings. See article abstract by Kuenen et al in Internet References section below.
See Also
Common Swift Moth (
K. lupulina) is yellowish-brown to orangish, forewing has highly-contrasting whitish ribbon-like marking, and in North America is currently known only from southern Ontario
species of
Sthenopis are much larger and have different markings on forewing (
compare images of 3 species at Canadian Forest Service)
Internet References
pinned adult images of
male and
female (Canadian Forest Service)
pinned adult image plus common name reference, habitat, flight season, description, foodplants, distribution (Strickland Entomological Museum, U. of Alberta)
adult images (Jonathan Leonard, U. of Vermont)
pinned adult images and collection site map (All-Leps)
larval foodplants and
distribution map (Buffalo Museum of Science, sciencebuff.org)
abstract of pheromone article (L.P.S. Kuenen
et al, Canadian Entomologist, courtesy trophort.com)
