Callophrys [Incisalia] polios
Hoary Elfin

Family Description:

Caterpillar: The caterpillar is pinkish to yellow when young and bright green when older. It is marked with a greenish line along the length of the back, faint diagonal dashes on the sides, and a white star on the back behind the head. It can reach a maximum length of 1/2 inch.
Adult: The butterfly is small, with a wingspan of 3/4 to 1 1/8 inches. It is grayish orange-brown on the upperside and unmarked. Underneath is brownish, with the interior portion of the hindwing noticeably darker. The underside of the forewing appears to be dusted with white along the outside edge, and is marked with a wavy line and a faint row of blackish dots. The outer half of the underside of the hindwing also appears dusted with white.

This species ranges from central Alaska south and east across Canada to Nova Scotia, south through the northeastern U.S. to Virginia; through the Great Lakes states; and in the western U.S. along the northern Pacific coast, in parts of Idaho, Montana, and south to New Mexico in patches.

It typically occurs in open dry areas such as rocky slopes and dunes; however, it is also occasionally found near forest bogs. Generally it is at sea level except in the Rocky Mountains where it is typically found above 8000 feet elevation.


Caterpillar: Caterpillars feed on bearberry (Arctostaphylos uva-ursi) and trailing arbutus (Epigaea repens).
Adult: Butterflies drink flower nectar.

There is one generation of caterpillars each summer; their coloring provides good camouflage when they are on the flowers of host plants. Pupae overwinter in a physiological state called diapause. Adults generally fly from April through May, occasionally into July.

Males perch on host plants to wait for receptive females. Females lay eggs singly at the bases of leaf buds or flowers of host plants.

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.