Variable Cracker (Hamadryas feronia [Linnaeus])
Wing span: 2 7/8 - 3 1/4 inches (7.3 - 8.3 cm).
Identification: Upperside of forewing is brown and white, sometimes bluish, with a red bar in the cell; hindwing eyespots are each black with a white center, surrounded by a blue ring. Underside of hindwing is white or tan-white with submarginal black rings.
Life history: Adults perch on tree trunks head downward with their wings spread open, and males make a cracking noise when they fly. Before dark, adults gather on a single tree, then disperse to roost in nearby trees or shrubs.
Flight: Throughout the year in the tropics, July-December in South Texas.
Caterpillar hosts: Vine Dalechampia in the family Euphorbiaceae.
Adult food: Rotting fruit and other non-floral resources.
Habitat: Tropical forest edges, cutover second growth.
Range: Argentina and Brazil north through tropical America to Mexico. Strays to the lower Rio Grande Valley of South Texas.
Conservation: Not required for a rare stray.
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.
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.