Pearl Crescent (Phyciodes tharos [Drury])
Wing span: 1 1/4 - 1 3/4 inches (3.2 - 4.5 cm).
Identification: Quite variable. Males usually have black antennal knobs. Upperside is orange with black borders; postmedian and submarginal areas are crossed by fine black marks. Underside of hindwing has a dark marginal patch containing a light-colored crescent. Spring and fall broods (form marcia) have a gray mottled hindwing below.
Life history: Males patrol open areas for females. Eggs are laid in small batches on underside of host plant leaves. Caterpillars eat leaves and are gregarious when young. Hibernation is by third-stage caterpillars.
Flight: Several broods; from April-November in the north, throughout the year in the Deep South and Mexico.
Caterpillar hosts: Several species of smooth-leaved true asters including Aster pilosus, A. texanus, and A. laevis.
Adult food: Nectar from a great variety of flowers including dogbane, swamp milkweed, shepherd's needle, asters, and winter cress.
Habitat: Open areas such as pastures, road edges, vacant lots, fields, open pine woods.
Range: Southeastern Alberta south through Montana, Wyoming, Colorado, New Mexico, Arizona, and southeastern California to Mexico; east to southern Ontario and all the eastern United States.
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.
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.