Rockslide Checkerspot (Chlosyne whitneyi [Behr])
Wing span: 1 1/4 - 1 5/8 inches (3.2 - 4.1 cm).
Identification: Upperside is slightly glossy black with pale orange to creamy white bands; female may be much darker. Underside of hindwing with a light orange marginal band, then alternating orange and creamy white bands on remainder of wing.
Life history: Males patrol and sometimes perch in hollows of rockslides to wait for females. Eggs are laid in batches on underside of host plant leaves and sometimes on flower buds. Caterpillars eat leaves and flowers, and feed together in groups. Third- and fourth-stage caterpillars hibernate under rocks; some diapause for two years or more to survive bad weather.
Flight: One flight from July-August.
Caterpillar hosts: Alpine plants of the sunflower family including Erigeron and Solidago species.
Adult food: Flower nectar.
Habitat: Rocky slopes, benches, and rockslides at or above treeline.
Range: Rare. British Columbia and Alberta south in the mountains to California and Colorado.
Conservation: Not usually required.
Management needs: None reported.
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:
Elrod, M.J. 1906. The Butterflies of Montana. Bulletin of the University of Montana 30: 1-174. 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.