Edwards' Fritillary (Speyeria edwardsii [Reakirt])
Wing span: 2 1/2 - 3 3/8 inches (6.3 - 8.6 cm).
Identification: Upperside of both wings tawny orange with black border and markings. Underside green or gray-green with narrow buff submarginal band and metallic silver markings.
Life history: Males patrol in open areas for females. Females lay eggs on litter near violets. First-stage unfed caterpillars hibernate; in the spring they eat host plant leaves.
Flight: One brood from late June to early September.
Caterpillar hosts: Violets including Viola nuttallii and V. adunca.
Adult food: Flower nectar.
Habitat: Short-grass prairie, foothills, meadows, fields, road edges.
Range: Short-grass prairie and western Rocky Mountains from southern Alberta east to the central Dakotas and western Nebraska, then south to northeastern New Mexico.
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 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.