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.
References:
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:
Brown, J.W., Real, H.G., and D.K. Faulkner. 1992. Butterflies of Baja
California. Lepidoptera Research Foundation, Beverly Hills, Calif.
Comstock, J.A. 1927. Butterflies of California. Privately published, Los
Angeles, Calif. [Facsimile available from Entomological Reprint
Specialists, Los Angeles, Calif.]
Dameron, W. 1997. Searching for butterflies in southern California.
Flutterby Press, Los Angeles, Calif.
Emmel, T.C. Editor. 1998. Systematics of western North American butterflies.
Mariposa Press, Gainesville, Florida.
Emmel, T. C. and J. F. Emmel. 1973. The Butterflies of Southern California.
Natural History Museum of Los Angeles County Science Series No. 26.
Garth, J.S. and J.W. Tilden. 1986. California Butterflies. California Natural
History Guide 51. University of California Press, Berkeley and Los
Angeles.
Langston, R.L. 1981. The Rhopalocera of Santa Cruz Island, California. Journal
of Research on the Lepidoptera 18: 24-35.
Miller, Scott E. 1985. Butterflies of the Califorenia Channel Islands. Journal
of the Research on the Lepidoptera 23: 282-296.
Opler, Paul A. 1999. Peterson Field Guide to Western Butterflies, revised
edition. Houghton Mifflin Co., Boston, Mass.
Orsak, L.J. 1977. The Butterflies of Orange County, California. Museum of
Systematic Biology, University of california, Irvine.
Stanford, R.E. and P.A. Opler. 1993. Atlas of Western USA Butterflies.
Privately published, Denver, Colo.
Steiner, J. 1990. Bay Area Butterflies: The Distribution and Natural History
of San Francisco Region Rhopalocera. Hayward, Calif.: Hayward State
University, Masters Thesis.
Tilden, J.W. and A.C. Smith. 1986. A Field Guide to Western Butterflies.
Houghton Mifflin Co., Boston, Mass.
Tilden, J.W. 1965. Butterflies of the San Francisco Bay Region. California
Natural History Guide 12. University of California Press, Berkeley and
Los Angeles.
