Western Pygmy-Blue (Brephidium exile [Boisduval])
Wing span: 1/2 - 3/4 inch (1.2 - 2 cm).
Identification: Tiny. Upperside copper brown with dull blue at the bases of both wings. Underside of hindwing is copper brown with white at the base; fringe mostly white; 3 small black spots near base; row of black spots at outer margin.
Life history: Males patrol over the host plants all day to find receptive females. Females lay eggs all over the host but particularly on the uppersides of leaves. Caterpillars eat all parts of the plant. Chrysalids hibernate.
Flight: July-September in the north, all year in South Texas.
Caterpillar hosts: Pigweed (Chenopodium album), saltbush species (Atriplex), and others in the goosefoot family (Chenopodiaceae).
Adult food: Flower nectar.
Habitat: Alkaline areas such as deserts, salt marshes, and wasteland.
Range: Common. Central California east to southern Nevada, central Arizona, central New Mexico, and west Texas. South through southern California, Baja California, and Mexico to Venezuela. Migrates to Arkansas, Nebraska, and Oregon.
Conservation: Not usually required.
The Nature Conservancy Global Rank: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Management needs: None reported.
Opler, P. A. and G. O. Krizek. 1984. Butterflies east of the Great Plains. Johns Hopkins University Press, Baltimore. 294 pages, 54 color plates. Opler, P. A. and V. Malikul. 1992. A field guide to eastern butterflies. Peterson field guide #4. Houghton-Mifflin Co., Boston. 396 pages, 48 color plates. 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:
Brown, F.M., Eff, J.D., and B. Rotger. 1957. Colorado Butterflies. Denver Museum of Natural History, Denver. 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.