Southern Dogface (Zerene cesonia [Stoll])
Wing span: 2 1/8 - 3 inches (5.4 - 7.6 cm).
Identification: Upperside forewings of both sexes have yellow "dog's head" surrounded by black. "Eye" does not touch black border. Female similar, with duller, more diffuse black areas and 2 seasonal forms: underside hindwing of wet season "summer" form is yellow; that of dry season "winter" form is mottled with black and pink.
Life history: Males patrol open areas for females. Eggs are laid on the undersides of terminal leaves of host plants. Adults overwinter in reproductive arrest.
Flight: Three flights in the southern states from May-June, July-August, and September-April. Northern colonists have one generation per year, or do not reproduce at all.
Caterpillar hosts: Small-leaved plants in the pea family (Fabaceae) including alfalfa (Medicago sativa); prairie clovers (Pentalostemon), indigo (Dalea), and clover (Trifolium) species.
Adult food: Nectar from flowers including alfalfa, coreopsis, houstonia, and verbena.
Habitat: Dry, open areas such as short-grass prairie hills, scrub oak groves, open woodland, washes, road edges.
Range: Resident in South America north to southern Texas and peninsular Florida. Stray or temporary resident from central California northeast through the Great Lakes area and all the eastern states.
Conservation: Not usually required.
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.
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:
Bailowitz, R. A. and J. P. Brock. 1991. Butterflies of Southeastern Arizona. Tucson, Ariz.: Sonoran Arthropod Studies, Inc. Garth, J.S. 1950. Butterflies of Grand Canyon National Park. Grand Canyon Natural History Association, Grand Canyon, Ariz. 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.