Poweshiek Skipperling (Oarisma poweshiek [Parker])
Wing span: 1 - 1 1/4 inches (2.5 - 3.2 cm).
Identification: Upperside is black; forewing leading edge and veins are orange. Underside of hindwing is pale brown with white veins.
Life history: To seek females, males patrol close to the ground with a rapid flight. Females deposit eggs singly on leaves of the host plants, which the caterpillars eat. Fifth-stage caterpillars hibernate.
Flight: One brood from June-August.
Caterpillar hosts: Spikerush (Eleocharis elliptica).
Adult food: Nectar from flowers including black-eyed susans, purple coneflower, ox-eye daisy, stiff-leaved coreopsis, and white clover.
Habitat: Undisturbed remnants of native tall-grass prairie.
Range: The Dakotas, Minnesota, one site in Iowa, and one site in Michigan.
Conservation: Because little of its habitat remains, this butterfly is in need of protection wherever it is found.
The Nature Conservancy Global Rank: G2 - Imperiled globally 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).
Management needs: Remaining habitats should be carefully managed. Use of fire as a management tool is discouraged.
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. 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. 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:
Layberry, R.A., Hall, P.W. & Lafontaine, D.J., 1998. The Butterflies of Canada. University of Toronto Press, Toronto, ON. 280 pp. Nielsen, Mogens C., 1999. Michigan Butterflies and Skippers: A Field Guide and Reference. Michigan State University Extension, East Lansing, MI. 248 pp. Opler, P.A. 1998. A field guide to eastern butterflies, revised format. Houghton Mifflin Co., Boston.