Synonyms and other taxonomic changes
Author: Couper, 1865
Adults - forewing length 10 - 13mm (1)
Larvae - 35mm
Adults - Lars Crabo explains: "Note this species of Alypia is sexually dimorphic, female Alypia langtoni only have 6 spots (one on hind wing) whereas males have 8 spots (two on hind wing). Males have rings on the antennal shafts which might not be visible on a photo whereas A. octomaculata does not."
Larvae - skin smooth, general color white with linear, irregular black markings (Crumb, 1955)
most of Canada from the Canadian Zone forests of southern Canada to the boreal forest and tundra regions of the Northwest Territories, the Yukon, and Alaska; eastern United States in northern and central Maine, northern New Hampshire, northern Vermont, and the Adirondack Mountains of upstate New York, northern Michigan and Minnesota, the mountains of the western United Statesd from the Canadian border east to western Montana and western South Dakota and south as far as the White Mountains of central Arizona, and California as far south as Santa Cruz County (Nearctica.com)
The most widespread Forester in Canada, ranging from Newfoundland & Labrador all the way to the Yukon. Adults with just one spot on each hindwing coupled with two on each forewing gives the species its common name.
Larvae feed on Fireweed (Epilobium) .