Grizzled Skipper (Pyrgus centaureae [Rambur])
Wing span: 1 - 1 5/16 inches (2.5 - 3.3 cm).
Identification: Fringes are checkered. Upperside is gray-black with squarish white checks. Underside of hindwing is gray-brown to black checkered with whitish spots; veins are white. Male has a costal fold enclosing scent scales on the forewing.
Life history: Males patrol and occasionally perch all day in open areas in their search for receptive females. Eggs are deposited singly on leaves of the host plant. Caterpillars feed within shelters of webbed leaves.
Flight: One brood from March-May in the south, requires 2 years to develop in the subarctic.
Caterpillar hosts: Wild strawberry (Fragaria virginiana), Canadian cinquefoil (Potentilla canadensis), varileaf cinquefoil (P. diversifolia), and cloudberry (Rubus chamaemorus); all in the rose family (Rosaceae).
Adult food: Nectar from flowers of low-growing plants including blueberry, wild strawberry, and Canadian cinquefoil.
Habitat: Open areas near woods including valley bottoms, barrens, meadows, grassy hillsides, tundra, scrub oak openings.
Range: Holarctic. In North America, from Alaska south and east to central Ontario and northern Michigan. Isolated populations in Labrador and arctic Quebec, the central Appalachians, and the Rocky Mountains from central Alberta south to northern New Mexico.
Conservation: Populations on eastern shale barrens (subspecies wyandot) should be monitored and conserved.
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: Determine management needs for subspecies wyandot and implement if necessary.
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. 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:
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.