Pallid Dotted-Blue (Euphilotes pallescens [Tilden and Downey])
Wing span: 5/8 - 13/16 inches (1.6 - 2.1 cm).
Identification: Upperside of male pale blue often without aurora. Upperside of female grayish brown with gray overscales on the wing bases. Underside almost white with distinct black spots; orange marginal hindwing band usually present but narrow.
Life history: Pallid Dotted-Blues stay near their host plants. Males patrol around the plants all day to find females. Eggs are laid singly on flowers of the host. Caterpillars feed on flowers and fruits, and are tended by ants.
Flight: One flight from early July to September.
Caterpillar hosts: Wild buckwheat species including Kearney's Buckwheat and Plumate Buckwheat.
Adult food: Nectar from Eriogonum flowers.
Habitat: Arid areas such as desert flats and edges of sand dunes.
Range: Southeast California, Nevada, southern Utah, and northern Arizona
Conservation: Some populations are of concern because of limited habitat or threats to habitats.
The Nature Conservancy Global Rank: G3,G4 - . Very rare or local throughout its range or found locally in a restricted range OR Apparently secure globally, though it might be quite rare in parts of its range, especially at the periphery. Several subspecies are rank T1 - Critically imperiled because of extreme rarity (5 or fewer occurrences, or very few remaining individuals), or because of some factor of its biology making it especially vulnerable to extinction. (Critically endangered throughout its range).
Management needs: Maintain habitat integrity. Monitor invasion by exotic weeds-primarily cheatgrass, and disruption by off-road vehicles.
Emmel, T.C., editor. 1998. Systematics of Western North American Butterflies. Mariposa Press, Gainesville, Fla. 878 pp. Emmel, T.C. and J.F. Emmel. 1973. The butterflies of southern California. Natural History Museum of Los Angeles County, Los Angeles. 148 pages. Garth, J.S. and J.W. Tilden. 1986.California Butterflies. University of California Press, Berkeley and Los Angeles. 246 pp, 24 plates. Opler, P.A. 1999. A field guide to western butterflies. Houghton-Mifflin Co., Boston, Mass. 540 pages, 44 color plates. Scott, J. A. 1986. The butterflies of North America. Stanford University Press, Stanford, Calif. 583 pages, 64 color plates. Stanford, R. E. and P. A. Opler. 1993. Atlas of western USA butterflies including adjacent parts of Canada and Mexico. Denver and Fort Collins, CO.
Author: Paul A. Opler
State and Regional References:
Ferris, C.D. and F.M. Brown. 1980. Butterflies of the Rocky Mountain States. University of Oklahoma Press. Norman. 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.