Esmeralda Longtail (Urbanus esmeraldus [Butler])
Wing span: 1 3/8 - 1 5/8 inches (3.5 - 4.2 cm).
Identification: Long tails. Upperside is dark blackish brown; body and wing bases are iridescent blue-green. Males have a costal fold enclosing scent scales on the forewing. Dark row on hindwing underside consists of separate spots.
Life history: Eggs are laid on young leaves of the host plant, which caterpillars eat.
Flight: Many flights from April-October in Mexico; August in South Texas.
Caterpillar hosts: Beggar's ticks (Desmodium).
Adult food: Flower nectar.
Habitat: Open subtropical woods and edges.
Range: Brazil and Paraguay north through the tropics to Mexico. A rare stray north to the lower Rio Grande Valley, Texas.
Conservation: Not necessary 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.