Zarucco Duskywing (Erynnis zarucco [Lucas])
Wing span: 1 5/8 - 1 7/8 inches (4.2 - 4.8 cm).
Identification: Forewing is narrow and pointed; hindwing is somewhat triangular. Upperside is dark brown with a reddish patch at the end of the forewing cell. Hindwing has brown fringes except for some individuals on the Florida Keys that have white fringes. Male has a costal fold containing yellow scent scales; female has a patch of scent scales on the 7th abdominal segment.
Life history: Eggs are laid singly under host plant leaves. Caterpillars feed on leaves and rest in shelters of rolled or tied leaves. Caterpillars from the last brood hibernate.
Flight: Three broods in the Deep South from March to early October, emerging as early as late January in Florida.
Caterpillar hosts: Herbaceous legumes including black locust (Robinia pseudacacia), hairy bush clover (Lespedeza hirta), Colorado River hemp (Sesbania exaltata), and Sesbania longifolia.
Adult food: Flower nectar including that from shepherd's needle.
Habitat: Wood edges, open fields, scrub.
Range: Southeastern United States from North Carolina south to the Florida Keys, west to eastern Texas and central Oklahoma. Strays north to eastern Pennsylvania and Connecticut. Occurs also on Cuba and Hispaniola.
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. 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.
Author: Jane M. Struttmann
State and Regional References:
Glassberg, J. 1993. Butterflies Through Binoculars: A Field Guide to Butterflies in the Boston-New York-Washington Region. Oxford Univ. Press, New York, N.Y. 160 pp. Layberry, R.A., Hall, P.W. & Lafontaine, D.J., 1998. The Butterflies of Canada. University of Toronto Press, Toronto, ON. 280 pp. Opler, P.A. 1998. A field guide to eastern butterflies, revised format. Houghton Mifflin Co., Boston. Shapiro, A.M. 1966. Butterflies of the Delaware Valley. American Entomological Society Special Publication. Philadelphia, PA. 79 pp. Tietz, H.M. 1952. The Lepidoptera of Pennsylvania. The Pennsylvania State College School of Agriculture Agricultural Experiment Station. State College, PA. 194 pp. Wright, D.M. 1995, Atlas of Pennsylvania Butterflies. Special Private Publication, Lansdale, PA. 22 pp.