Pale Crescent (Phyciodes pallida [W. H. Edwards])
Wing span: 1 3/8 - 1 5/8 inches (3.5 - 4.1 cm).
Identification: Upperside is pale orange; dark markings are reduced, especially on hindwing. Forewing both above and below with dark spot at center of inner margin. Underside is yellow with red-brown markings; crescent on hindwing is white.
Life history: Males perch in canyons to wait for females; only rarely do they patrol ridges. Females lay eggs in large groups on underside of host plant leaves; caterpillars eat leaves.
Flight: One flight from April-June.
Caterpillar hosts: Thistles (Cirsium) in the sunflower family.
Adult food: Flower nectar.
Habitat: Valleys, dry streambeds, dry fields.
Range: Central British Columbia southeast in the Rocky Mountains to Montana, Wyoming, and Colorado; south to Oregon, Utah, Nevada, and northern Arizona.
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.
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:
Brown, F.M., Eff, J.D., and B. Rotger. 1957. Colorado Butterflies. Denver Museum of Natural History, Denver. 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.