Colias pelidne
Pelidne Sulphur

Family Description:
Alternate Common Name: Blueberry Sulphur.
Caterpillar: A detailed scientific description of the caterpillar has not been published.
Adult: This is a small to medium-sized butterfly, with a wingspan of 1 to 1 inches. The male is pale yellow on the upperside, with a black border edging the wings, a small dark spot on the forewing and possibly a faint orange spot on the hindwing. Females can be white or yellow on the upperside, with a faint or interrupted black wing border and similar spots. Underneath, both sexes are yellow to white, with a spot on the hindwing and possibly on the forewing, and black shading which makes the wings appear to be dusted with soot. The wings have a pinkish fringe.

This species occurs in eastern Alaska, in the Rockies from southern Alberta to Wyoming, and in the far northeastern portion of Canada. It occurs throughout much of Idaho.

It generally occurs in high elevation habitats such as tundra or subalpine meadows and forest openings.


Caterpillar: Caterpillars feed on species of blueberry (Vaccinium spp.) and on wintergreen (Gaultheria humifusa).
Adult: Butterflies drink flower nectar.

There is one generation of caterpillars each summer. Adults generally fly from the end of June to September. Little about the life cycle of this species is known or reported in the scientific literature.

Males actively patrol for receptive females. The sites chosen by females for laying eggs has not been observed or reported.

Idaho Status: Unprotected nongame species.
Global Rank:

G5; populations are widespread, abundant, and secure.

Ferris, C. D. and F. M. Brown. (eds.) 1981. Butterflies of the Rocky Mountain States. Univ. of Oklahoma Press, Norman, Oklahoma, USA, 442 pp.

Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. (Version 05Nov98).

Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies.   Second Edition.  Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.

Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.

Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.

Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.