Thymelicus lineola
European Skipper

Family:Hesperiidae
Family Description:
Alternate Common Name: European Skipperling.


Description:
Caterpillar:
The caterpillar is green and marked lengthwise with a dark stripe along the back and two yellow lines along each side. The head is tan and the face is striped with yellow.
Adult: This is a fairly small skipper, with a wingspan of 3/4 to 1 1/8 inch. The wings appear somewhat squared off and are golden orange to brownish orange on the upperside, bordered with black. The wing veins are outlined in black, particularly thick near the outer edges. Males have a small stigma (patch of scent scales used in attracting females) on the forewing, which looks like a diagonal black streak near the center. Underneath, the forewing is orange while the hindwing ranges in color from greenish yellow to greenish gray to brownish orange.

Range:
This skipper occurs in two distinct populations in North America. In the east, it ranges from southeastern Manitoba to Newfoundland and south to northeastern Missouri and Tennessee. In the west, it occurs in British Columbia, Idaho, Montana, and Colorado. Its range is continuing to expand.

Habitat:
It can be found in fields, meadows, pastures, and other grassy places.

Diet:
Caterpillar:
Caterpillars feed on the leaves of timothy (Phleum pratense) and other grasses.

Adult: Butterflies drink nectar from short-stemmed flowers such as clover (Trifolium spp.), milkweed (Asclepias spp.), and thistle (Cirsium spp.).

Ecology:
Eggs overwinter and hatch in the spring. There is one generation of caterpillars each summer. Caterpillars live in nests made of leaves tied with silk. Adults generally fly from mid-May to mid-July. Butterflies roost at night in tall grasses; in some areas, the butterflies have been observed roosting together by the hundreds. A strange and detrimental behavior of some of the butterflies, reported by one expert, is crawling within orchid flowers (Cypripedium spp.) in search of nectar. Once inside the flower, the butterfly is trapped and cannot get out. Interestingly, native skippers have not been observed behaving similarly. The European Skipper was introduced to Ontario, Canada from Europe in 1910 and to British Columbia in 1960, and the species has spread considerably since. Its progressive expansion is believed by experts to be the result of the inadvertent transport of its eggs through the shipment of hay.

Reproduction:
Males actively patrol all day among grasses in search of receptive females. Strings of eggs are laid on the stems of grasses.

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


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.