Pyrgus centaureae
Grizzled Skipper

Family:Hesperiidae
Family Description:
Alternate Common Name: Alpine Checkered Skipper.
Description:
Caterpillar: Scientists currently have not described the caterpillar in detail.
Adult: This skipper is fairly small to medium-sized, with a wingspan of 1 to 1 inches. It varies slightly in its size and color according to location, with western individuals being larger and paler than those found in the east. Typically, the upperside is dark brown and marked with white square-shaped spots; the hindwing has fewer and less distinct spots than the forewing. There may be a patch of short yellow hairs on the wings above, and there is a black-and-white checkered fringe as a border. Underneath is grayish brown and checked with white; the white marks may form continuous bands. The fringe from  below is noticeably black-and-white checked. Males possess scent scales, used in attracting females, in a small, folded over section of the leading edge of the forewing (called a costal fold). Males also have tibial tufts, specialized hairs on the fourth segment of the hind leg, which are used to waft pheromones (sex attractant chemicals) to a female during mating. The hairs are tucked into special pockets on the body during flight.

Range:
This species ranges from central Alaska south and east to Manitoba and Ontario, and throughout northeastern Canada. It also extends through British Columbia to northern Washington, central Idaho, and western Montana. Isolated populations occur in the Rockies, Great Lakes, and Appalachians.

Habitat:
The preferred habitat varies across its Range: mountainous or subarctic coniferous forests in the west and north, scrubby oak woodlands in the Great Lakes, and heath or pine barrens in the east.

Diet:
Caterpillar:
Caterpillars feed on members of the rose family (Rosaceae), such as cinquefoils (Potentilla spp.), wild strawberry (Fragaria virginiana), and blackberry (Rubus chamaemorus).

Adult: Butterflies drink flower nectar, often from yellow flowers.

Ecology:
There is one generation of caterpillars each summer. Caterpillars construct feeding shelters from leaves tied with silk. While the overwintering stage is not verified, it is believed that in some parts of its range (primarily the far north), individuals require two years to fully develop. Adults generally fly from May to August.

Reproduction:
Males actively patrol and may occasionally perch to wait for receptive females. Females lay eggs singly on the leaves of host plants.

Conservation:
Idaho Status: Unprotected nongame species.
Global Rank: G5
populations are widespread, abundant, and secure.However, the subspecies P. centaureae wyandot in the east may be declining.


References:
Ferris, C. D. and F. M. Brown. (eds.) 1981. Butterflies of the Rocky Mountain States. Univ. of Oklahoma Press, Norman, Oklahoma, USA, 442 pp.

Opler, P. A., H. Pavulaan, and R. E. Stanford. 1995. Butterflies of North America. Jamestown, North Dakota, USA: Northern Prairie Wildlife Research Center Home Page. http://www.npwrc.usgs.gov/resource/distr/lepid/bflyusa/bflyusa.htm (Version 05Nov98).

Opler, P. A. and A. B.Wright. 1999. A Field Guide to the Western Butterflies.   Second Edition.  Peterson Field Guide Series. Houghton Mifflin Company, New York, New York, USA, 540 pp.

Pyle, R. M. 1981. National Audubon Society Field Guide to North American Butterflies. Alfred A. Knopf, Inc., New York, New York, USA, 924 pp.

Scott, J. A. 1986. The Butterflies of North America. Stanford University Press, Stanford, California, USA, 583 pp.

Stanford, R. E. and P. A. Opler. 1993. Atlas of Western U.S.A. Butterflies (Including Adjacent Parts of Canada and Mexico). Published by authors, Denver, Colorado, USA, 275 pp.