Canada Sulphur

Resident in northern North America (Scott 1986). Habitats are LUSH ARCTIC/ALPINE ZONE TUNDRA AND HUDSONIAN TAIGA. Host plants are usually herbaceous with most known hosts a few species from LEGUMINOSAE. There is one flight each year with the approximate flight time JUNE1-JUL15 (Scott 1986). Sometimes listed as a sub-species of Colias hecla.

Not of concern.

One yearly brood peaking from late May to late July, depending on habitat.

Eastern Alaska to northern BC and Alberta (Opler 1999), south in the Alberta foothills to Highwood Pass (Layberry et al. 1998).

The only other Alberta Colias with a dorsal orange colour that extends all the way to the forewing base are meadii and eurytheme. The Canada Sulphur, however, has the pink outline of the underside discal spot smeared outwards, and almost always lacks the hindwing underside submarginal dark spots. This species was only recently found to be distinct from C. hecla by Cliff Ferris (1988).

Moist, open areas including shrub willow-birch valley bottoms and alpine tundra.

The mature larva overwinters, and is dark green covered with short, fine hairs arising from small black spots (Guppy & Shepard 2001). The dorsal line is dark, and the lateral line is white and pinkish-red (Guppy & Shepard 2001).

The larval foodplants are unkown, but are likely to be legumes. Females lay eggs on Hedysarum (Fabaceae) in captivity, and larvae can be successfully reared on red clover (Guppy & Shepard 2001).

Colias canadensis, the Canada sulphur, is a butterfly in the family Pieridae found in North America. It has only been found from Alaska and Northwest Territories, to northern British Columbia and Alberta.

Flight period is early May to early August. Its habitats include open taiga forests, wet tundra, mountain valleys, and alpine tundra near tree lines.

Wingspan is from 32 to 47 mm.