European Skipper (Thymelicus lineola) (Ochsenheimer, 1808)

Diagnosis: This small (wingspan: 19 to 26 mm) skipper is bright brassy orange above with narrow black borders on both wings, and the ends of the veins are outlined in black. The males have a very narrow black stigma, and females usually have a thin vertical black vein at the end of the forewing cell. Below, the forewings are pale orange and the hindwings are greyish brown. Occasionally very pale specimens (form "pallida") are seen.

Subspecies: Only the nominate subspecies is found in North America.

Range: Thymelicus lineola is found across temperate Eurasia and northwestern Africa, and, since its original introduction into North America, has spread throughout the northeastern U.S. and eastern Canada from Newfoundland to southeastern Manitoba. There are isolated colonies in Saskatchewan, Alberta, central and southern British Columbia, and on the James Bay Highway in northern Quebec.

Specimen collection data

Similar Species: None.

Description of this image follows.
European Skipper (Thymelicus lineola), larva. W. Lukey

Early Stages: The larvae are green with a dark dorsal stripe and a whitish subdorsal and lateral stripe; the head is whitish green with three vertical reddish-brown bars with two white bars between them. The preferred foodplant is Timothy Grass (Phleum pratense), but they also eat other grasses, including Cocksfoot (Dactylis glomerata) and Couch Grass (Agropyron repens). The eggs are laid in groups of up to 30, on the leaf sheath or on the seed-heads; among North American skippers this is the only species whose eggs hibernate.

Abundance: In many places in the east the species is unbelievably abundant, outnumbering all other species combined. Even after almost a century it seems that native parasites have not yet developed a"taste" for this species.

Flight Season: There is one generation per year, in most places from early June to mid-July, extending to mid-August in Newfoundland.

Habits: Most abundant in agricultural areas where Timothy Grass is grown for hay, lineola has spread to just about every kind of grassy area in the range, including city parks and gardens, forest trails and clearings, marshes, bog edges, and roadsides in every habitat.

Remarks: The unique overwintering eggs of the European Skipper permitted the original introduction into North America, near London, Ontario, about 1910, in contaminated imported seeds of Timothy Grass. Even modern seed-cleaning techniques do not totally remove the eggs, and to make things worse, the waste, containing vast numbers of eggs, is sometimes combined with hay and transported as well.

Introductions continue; when the James Bay Highway was built in the late 1970s, roadsides in clay areas were stabilized with southern clovers and grasses, including Timothy Grass, probably using mixed uncleaned seed from western Quebec. This has created suitable habitat for the European Skipper and along long stretches of the highway, at least as far north as the Rupert River, lineola is the most common butterfly in mid-July. This is perhaps not too surprising, since it flies in Europe to 62° N; probably only lack of suitable habitat has prevented it spreading farther in Canada.

© 2002. This material is reproduced with permission from The Butterflies of Canada by Ross A. Layberry, Peter W. Hall, and J. Donald Lafontaine. University of Toronto Press; 1998. Specimen photos courtesy of John T. Fowler.