Western Green Hairstreak (Callophrys affinis [W. H. Edwards])
Wing span: 1 - 1 1/8 inches (2.5 - 3 cm).
Identification: No tails. Adults variable. Upperside ranges from gray to orange-tinted to bright orange-brown. Underside of forewing green with orange or gray patch. Underside of hindwing yellow-green to green; postmedian white line usually reduced to a few spots.
Life history: Males perch on hilltops or in gulches to seek females. Eggs are laid singly on flower buds of host plants; caterpillars feed on flowers and young fruits, and occasionally leaves. Chrysalids hibernate.
Flight: One flight from May-July.
Caterpillar hosts: Various Eriogonum, Lotus, and Ceanothus species.
Adult food: Flower nectar.
Habitat: Brushland, chaparral, woods, scrub.
Range: Southern British Columbia and Washington south through California into northern Baja California; east to central Montana, Wyoming, Colorado, and New Mexico.
Conservation: Not usually required.
The Nature Conservancy Global Rank: G4 - Apparently secure globally, though it might be quite rare in parts of its range, especially at the periphery.
Management needs: None reported.
Scott, J. A. 1986. The butterflies of North America. Stanford University Press, Stanford, Calif. 583 pages, 64 color plates. Tilden, J. W. 1986. A field guide to western butterflies. Houghton-Mifflin Co., Boston, Mass. 370 pages, 23 color plates.
Author: Jane M. Struttmann
State and Regional References:
Elrod, M.J. 1906. The Butterflies of Montana. Bulletin of the University of Montana 30: 1-174. Ferris, C.D. and F.M. Brown. 1980. Butterflies of the Rocky Mountain States. University of Oklahoma Press. Norman. Layberry, R.A., Hall, P.W. & Lafontaine, D.J., 1998. The Butterflies of Canada. University of Toronto Press, Toronto, ON. 280 pp. Opler, Paul A. 1999. Peterson Field Guide to Western Butterflies, revised edition. Houghton Mifflin Co., Boston, Mass. Stanford, R.E. and P.A. Opler. 1993. Atlas of Western USA Butterflies. Privately published, Denver, Colo. Tilden, J.W. and A.C. Smith. 1986. A Field Guide to Western Butterflies. Houghton Mifflin Co., Boston, Mass.