Red-disked Alpine (Erebia discoidalis [Kirby])
Wing span: 1 1/2 - 1 15/16 inches (3.8 - 4.9 cm).
Identification: Wings are brownish black and lack eyespots. Forewing has a large chestnut red patch both above and below. Underside of hindwing is mottled gray and brown.
Life history: Adults fly slowly near the ground. Males patrol for females with a weak flight. Fourth-stage caterpillars hibernate; probably biennial.
Flight: One brood from early May to mid-June.
Caterpillar hosts: Bluegrasses (Poa species).
Adult food: Flower nectar.
Habitat: Large, open, grassy bogs; other areas with acidic soils.
Range: Holarctic. North America from Alaska south and east to southern Alberta, northern Montana, northern Wisconsin, northern Michigan, and southern Quebec.
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