Other Common Names
Dusky-wings
Duskywings (not recommended because that name is already in popular use for skippers in the genus
Erynnis)
Numbers
52 species in 8 genera in North America (
nearctica.com)
Identification
Adult: covered with white waxy powder which gives a granulated appearance to the surface when viewed close-up; wings whitish with reduced venation, and held tent-like over abdomen when at rest; antennae long and slender; mouthparts moderately long and beak-like; legs relatively long, especially hindlegs.
Wing venation of Semidalis:
Larva: five simple eyes on each side of head, and needle-like jaws
Range
most of United States and southern Canada
Habitat
low woody and herbaceous plants
Season
most active at dawn and dusk in spring and fall
Food
adults and larvae feed on aphids, mealybugs, spider mites, scale insects, whiteflies, and other soft-bodied arthropods
Life Cycle
adults flutter slowly among plants and usually lay single eggs on bark or leaves; two generations per year; overwinters as a larva
Remarks
generally considered uncommon but easily overlooked due to small size and
crepuscular habits; may be a more economically important predator of homopteran pests than previously realized
See Also
adult is similar to
whiteflies (Aleyrodidae) but has longer legs - especially the hindlegs - longer antennae, longer beak-like mouthparts, and wings held tent-like at a more vertical angle over the abdomen when at rest
Internet References
live adult image (Steve Marshall, U. of Guelph, Ontario)
preserved adult image (Insects of Cedar Creek, Minnesota)
live larva image (Jack Kelly Clark, U. of California)
biology info (Colin Stewart and Nancy Coverstone, U. of Maine)
biology info and details of waxy covering (Dennis Nelson
et al, US Dept. of Agriculture)
