Lycaena cupreus
Lustrous Copper

Family Description:

Caterpillar: The caterpillar is light green, or less commonly reddish; it may be marked with a red stripe along the side and reddish marks along the back. The average, full-grown length of the caterpillar is inch.
Adult: This is a fairly small to medium-sized butterfly, with a wingspan of 1 to 1 inches. The male is shiny, bright orange-red on the upperside, marked with a black border, black dots, and a white fringe. The female is yellowish orange, with a brown border and fairly large brown spots. Underneath, both sexes are very light brown to yellowish white and marked with black or brown spots. The underside of the forewing may be clouded with orange, and it is marked with a curved line of blackish dots along the outside edge; the same line on the underside of the hindwing is orange to red.

This species occurs at high elevations, from southern British Columbia to New Mexico, and from central Oregon to central California. In Idaho, it occurs in portions of the southern half of the state.

It can be found at high elevations, typically in meadows, along streams, and on rocky slopes.


Caterpillar: Caterpillars feed on the leaves of certain members of the buckwheat family (Polygonaceae), including alpine sorrel (Rumex spp.) and mountain sorrel (Oxyria spp.).
Adult: Butterflies drink flower nectar.

There is one generation of caterpillars each summer. Each caterpillar undergoes four stages of growth, called instars. Caterpillars overwinter in a physiological state called diapause. Adults generally fly from May or June until August or September.

Males perch to wait for receptive females, or may occasionally actively patrol for them. Females lay eggs singly on or near host plants.

Idaho Status: Unprotected nongame species.
Global Rank: G5; populations are widespread, abundant, and secure.

Ballmer, G. R. and G. F. Pratt. 1988. A survey of the last instar larvae of the Lycaenidae of California. Journal of Research on the Lepidoptera 27:1-81.

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.