North American Butterflies and Moths List

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Butterflies of North America

Butterflies of Texas

Dusky-blue Groundstreak (Calycopis isobeon)
JPG -- species photo

Dusky-blue Groundstreak (Calycopis isobeon [Butler & Druce])

Wing span: 7/8 - 1 1/4 inches (2.2 - 3.2 cm).

Identification: Two tails on the hindwing. Underside of both wings gray-brown; inner edge of postmedian line bordered narrowly with red-orange. Underside of hindwing has eyespot at lower apex with equal amounts of orange and black.

Life history: Eggs are laid in leaf litter on the ground. Caterpillars eat dead leaves and fruits, and detritus.

Flight: Many flights from January-September in Texas and Mexico.

Caterpillar hosts: Dead leaves and fruits, and detritus, especially under trees in the cashew family (Anacardiaceae).

Adult food: Flower nectar.

Habitat: Subtropical valley bottoms and lowland forest edges.

Range: Venezuela north through Central America and Mexico to central and South Texas. Strays into Mississippi and Kansas.

Conservation: Not usually required.

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 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.

Author: Jane M. Struttmann

State and Regional References:

Neck, R.W. 1996. A Field Guide to Butterflies of Texas. Gulf Publishing Co., 

     Houston, Texas.

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.


Tveten, J. and Tveten, G.  1996.  Butterflies of Houston & Southeast Texas.

     Univ. of Texas Press, Austin, TX.  292 pp.


Dusky-blue Groundstreak (Calycopis isobeon)
distribution map
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