Strecker's Giant-Skipper (Megathymus streckeri [Skinner])
Wing span: 2 1/4 - 3 1/16 inches (5.7 - 7.8 cm).
Identification: Forewings are wide. Upperside is black; forewing has white spots near the tip and a yellow band; hindwing has a white to yellow marginal band and long hairlike scales. Underside of hindwing is gray or mottled gray and black, and has few to several white spots.
Life history: Females make clicking noises during flight. Adults bask on old yucca stalks with their hindwings spread; the uppersides resemble old seedpods. To await receptive females, males perch and sometimes patrol all day around the host plants. Females glue eggs singly on leaves of the host plant. A young caterpillar burrows into the stem to the root without making a tent. After hibernating in the burrow, the caterpillar surfaces through the stem or soil and constructs a tent of silk, soil, and plant debris in which to pupate. Chrysalids can move about in their tent.
Flight: One brood from May-July.
Caterpillar hosts: Small soapweed (Yucca glauca), Buckley yucca (Y. constricta), fineleaf yucca (Y. angustissima), and Bailey's yucca (Y. baileyi).
Adult food: Adults do not feed, but males sip moisture from mud.
Habitat: Sand hills, rocky bluffs, short-grass prairie, shrubland, open woodland.
Range: Southeastern Montana and southwestern North Dakota south to South Texas, west to northwestern Arizona and southwestern Utah.
Conservation: Not usually required.
The Nature Conservancy Global Rank: G4 - Apparently secure globally, though it might 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. Riley, T.J. 2001. Range Extension and New State Record for Strecker's Giant Skipper, Megathymus streckeri texanus Barnes & McDunnough (Lepidoptera: Hesperiidae: Megathyminae). Manuscript in review. 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:
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.