Ellis Dotted-Blue (Euphilotes ellisi [Shields])
Wing span: 3/4 - 7/8 inches (1.9 - 2.2 cm).
Identification: Male blue above with narrow black outer borders and narrow pink band on outer edge of hindwing. Female brown or with extensive blue. Orange hindwing band moderate to small. Underside of forewing has submarginal row of dark spots smudged and continuous red-orange band on outer margin of hindwing.
Life history: Males patrol all day near host plants to find receptive females. Eggs are laid singly on host plant flowers; caterpillars eat flowers and fruits, and are protected by ants. Chrysalids hibernate in sand or leaf litter.
Flight: One flight from mid-July to early September.
Caterpillar hosts: Corybose and Heerman buckwheats.
Adult food: Flower nectar especially that from Eriogonum species.
Habitat: Dry rocky or gravelly slopes or flats.
Range: Utah and western Colorado south to northwestern New Mexico and n. Arizona. Also western Nevada and eastern California.
Conservation: All or most populations are or may be susceptible to invasion and decline due to cheatgrass.
The Nature Conservancy Global Rank: G2,G3 - for species imperiled because of rarity (6 to 20 occurrences), or because of other factors demonstrably making it very vulnerable to extinction throughout its range. (Endangered throughout its range). OR very rare or local throughout its range or found locally in a restricted range . All named subspecies are of conservation concern.
Management needs: Maintain habitat together with host plants of all known populations. Monitor populations and presence of invasive weeds, especially cheatgrass.
Emmel, T.C., editor. 1998. Systematics of Western North American Butterflies. Mariposa Press, Gainesville, Fla. 878 pp. Ferris, C.D. and F.M. Brown. 1981. Butterflies of the Rocky Mountain States. University of Oklahoma Press, Norman. 442 pages. 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