Satyrium behrii
Behr’s Hairstreak

Family Description:
Alternate Common Name:
Orange Hairstreak.
Note: Some authors refer to this species using the genus name Callipsyche.

Caterpillar: The caterpillar is green, marked lengthwise with white, yellow, and/or dark green stripes along the back and sides, and covered with short yellow hair. It reaches an average, full-grown length of 1/2 inch.
Adult: The butterfly is small, with a wingspan of 7/8 to 1 1/4 inches. The upperside is bright golden orange edged thickly with dark brown. Males have a stigma, a patch of scent scales used in attracting females, on the forewing. Underneath, males are brown while females are brownish gray. There is an irregular line of black bars, edged with white, on the underside of the forewing; the underside of the hindwing is similarly but more randomly marked. The underside is additionally marked with a row of black spots, possibly dotted with white, along the outside edge. While most species of Hairstreaks have a thin tail extending from the rear of the hindwing, this species does not.

It occurs from southern British Columbia south along the various mountain ranges to southern California, and east to southern Idaho, western Wyoming and Colorado, and central New Mexico.

This species is found in dry habitats including sagebrush steppe, chaparral, and pinyon-juniper woodlands.


Caterpillar: Caterpillars eat the leaves of bitterbrush (Purshia spp.).
Adult: Butterflies drink flower nectar, often from wild buckwheat (Eriogonum spp.).

Eggs are laid in the fall, overwinter, and hatch in the spring. There is only one generation of caterpillars each year. The caterpillar is equipped with a honey gland, also known as a dorsal nectary organ, which emits a sugary solution agreeable to ants. The ants feed on the solution and in turn protect the caterpillar from predators. Each caterpillar undergoes four stages of growth, called instars. Adults generally fly from May through August. Butterflies tend to stay near host plants and are fairly local within the described range of the species.

Males perch on shrubs located on hilltops to wait for receptive females. Greenish white eggs are laid singly on the leaves and branches of bitterbrush (Purshia spp.). The eggs turn white before hatching.

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.