False Duskywing (Gesta gesta [Herrich-Schäffer])
Wing span: 15/16 - 1 3/8 inches (2.4 - 3.5 cm).
Identification: Upperside brown-black with darker bands; forewing with blue-gray submarginal band and a dark patch overlapping the cell.
Life history: Adults stay near the host plants, where females lay eggs. Caterpillars rest during the day in leaf nests and come out at night to feed on leaves. Fully-grown caterpillars hibernate.
Flight: Four broods from April-November in South Texas; all year southward.
Caterpillar hosts: Wild indigo (Indigofera suffruticosa and I. lindheimeriana) in the pea family (Fabaceae).
Adult food: Flower nectar.
Habitat: Tropical open areas including thornscrub, dry riverbeds, and abandoned fields.
Range: Argentina north through tropical America to the West Indies and South Texas. A stray to east Texas.
Conservation: Monitor populations in South Texas, and take action if necessary.
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 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. Stanford, R. E. and P. A. Opler. 1993. Atlas of western USA butterflies including adjacent parts of Canada and Mexico. Denver and Fort Collins, CO. 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:
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.