Identification: Males and females differ; plus 2 seasonal forms. Upperside of male forewing yellow with black bar along inner edge and a large black area at apex. Female varies from yellow to white; forewing with gray-black on apex and black patch on outer edge of hindwing. Summer (wet season) form is smaller with more extensive black areas. Underside hindwing of summer form is satiny white; that of winter form is brick red or tan with two small black spots in cell. In southern Florida, some individuals have white hindwings.
Wing Span: 1 1/4 - 1 5/8 inches (3.2 - 4.1 cm).
Life History: Males patrol open areas for females. Females lay single eggs on the terminal growth of host plants. Caterpillars eat leaves. Non-reproductive dry season adults overwinter.
Flight: Throughout the year in the Deep South, late summer and fall as vagrant.
Caterpillar Hosts: Pencil flower (Stylosanthes biflora), joint vetches (Aeschynomene species), and other plants in the pea family (Fabaceae).
Adult Food: Nectar from a great variety of flowers including joint vetches and shepherd's needle.
Habitat: Tropical and subtropical dunes, pastures, open pine woods.
Range: Argentina north to the United States Deep South; stray to southern Arizona, South Dakota, South Texas, and Washington, D. C.
Conservation: Not usually required.
NCGR: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
Management needs: None reported.
The Nature Conservancy Global Rank: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.
DeVries, P. J. 1987. The butterflies of Costa Rica and their natural history. Princeton University Press, Princeton, New Jersey. 327 pages, 50 color plates. 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. 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:
Glassberg, J. 1993. Butterflies Through Binoculars: A Field Guide to Butterflies in the Boston-New York-Washington Region. Oxford Univ. Press, New York, N.Y. 160 pp. Layberry, R.A., Hall, P.W. & Lafontaine, D.J., 1998. The Butterflies of Canada. University of Toronto Press, Toronto, ON. 280 pp. Opler, P.A. 1998. A field guide to eastern butterflies, revised format. Houghton Mifflin Co., Boston. Woodbury, E.N. 1994. Butterflies of Delmarva. Delaware Nature Society, Inc., Tidewater Publishers, Centreville, MD. 138 pp. [NOTE: this book only treats True Butterflies (Papilionoidea). It does not treat Skippers (Hesperioidea).]