Old World Swallowtail (Papilio machaon Linnaeus)
Wing span: 2 1/2 - 3 inches (6.5 - 7.5 cm).
Identification: Upperside of hindwing near tail has reddish-orange eyespot with black along lower border touching inner edge of hindwing or at least not a centered eyespot.
Life history: Females lay eggs singly on the host plant, and newly-hatched caterpillars eat the leaves. Older caterpillars feeding on plants of the parsley family prefer to eat the flowers. Chrysalids overwinter.
Flight: In north, one flight in late May-July; two flights in south.
Caterpillar hosts: Sagebrushes (Artemisia species), including Arctic wormwood and wild tarragon, rarely plants in the parsley family.
Adult food: Flower nectar.
Habitat: Open hilltops, mountain meadows, tundra.
Range: Holarctic. In North America, south from Alaska to northern British Colombia, east across Canada to western Quebec. Southern British Colombia south through New Mexico.
Comments: Includes , P. oregonius and P. bairdii.
Conservation: Not noted as of concern, but is rare or uncommon.
Management needs: None noted.
The Nature Conservancy Global Rank: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
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:
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.