Lycaena mariposa
Mariposa Copper

Family Description:
Alternate Common Name:
Forest Copper.
Note: This species is referred to with the genus name Epidemia by some authors.

Caterpillar: The caterpillar is green and may be marked with yellow along the side. Its average, full-grown length is 5/8 inch.
Adult: The butterfly is fairly small to medium-sized, with a wingspan of 1 to 1 1/4 inches. The male is coppery brown on the upperside with a purplish sheen, and it is marked with pale brownish spots and crescents. The female is yellowish orange on the upperside of the forewings, marked with dark brown spots and light brown along the outside edge and near the body. The hindwing is mostly brown and marked with zigzag lines of yellowish orange. Underneath, both sexes are peach to grayish orange on the forewing, edged with brown and spotted with black. The underside of the hindwing is mottled grayish white to dark gray and marked with thin black crescents, curving towards the body. A very dark form is reported to occur in northern Idaho at low elevation.

This species ranges from southern Alaska south through British Columbia and Alberta, through the Pacific Northwest east to central Montana and Wyoming, and south into northcentral California. In Idaho, it occurs primarily in the northern and central sections of the state.

Preferred habitat includes forest bogs and openings.


Caterpillar: While records are sparse, it is thought that caterpillars feed on certain members of the heath family (Ericaceae), such as huckleberry (Vaccinium spp.) or on plants belonging to the buckwheat family (Polygonaceae).
Adult: Butterflies drink flower nectar.

Eggs overwinter and hatch in the spring, and the resulting brood of caterpillars is the only one each year. Each caterpillar undergoes four stages of growth, called instars. Adults generally fly from July through September. It is not uncommon to observe large numbers of adults in a given area. The word "mariposa" is Spanish for "butterfly."

Males perch to wait for receptive females. The typical locations of oviposition are unreported.

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.