Epargyreus clarus
Silver-Spotted Skippe

Sub-Family Description:

Caterpillar: The caterpillar is yellowish green, striped around the body with dark rings, with a reddish black head spotted with yellowish orange. The legs and "throat" region (behind the head on the underside) are reddish.
Adult: This is a fairly large skipper, with a wingspan of 1 3/4 to 2 5/8 inches. The upperside is several different shades of brown, with transparent patches of golden yellow on the main portion of the forewing and several spots near the tip. The hindwing has a small lobe (rounded projection) extending off the bottom portion. Underneath is brownish, with a fairly large white to silver patch on the hindwing.

This is a widespread species of the U.S., ranging from the extreme northeast through the entire eastern half of the U.S., and west to the north Pacific Coast and parts of California and the southwest. It is found scattered throughout Idaho.

It can be found in canyons, open woodlands, prairies, and along streams.

Caterpillars eat the leaves of a variety of tree and herbaceous legumes, including locusts (Robinia and Gleditsia spp.), tick-trefoils (Desmodium spp.), and beans (Phaseolus spp.).

Adult: Butterflies drink flower nectar, typically from flowers colored blue, red, pink, or purple.

Young caterpillars live in shelters made from folded leaves, while older caterpillars live in nests made of silk and leaves. The number of generations of caterpillars each summer depends on the location, with one in the north and west, two in the east, and three or four in the south. Pupae overwinter in a physiological state called diapause. In the case of multiple generations of caterpillars in a single growing season, only the last generation overwinters after pupating. Adults generally fly from late May to July. Butterflies hang upside down from leaves.

Males perch to wait for receptive females, or may actively patrol for them. Females lay greenish eggs singly on the leaves of host plants or on plants near host species.

Idaho Status: Unprotected nongame species.
Global Rank: G5
populations are widespread, abundant, and secure.


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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).

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