Uhler's Arctic
Oeneis uhleri (Reakirt, 1866)
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Diagnosis: The upperside is dull greyish brown, with up to five eye-spots on each wing; these are more developed on the hindwing with the largest eye-spots sometimes having white pupils. The eye-spots are repeated beneath. The underside of the hindwing is coarsely striated in dark brown and buff, and the outer half of the wing is much paler than the base. Wingspan: 35 to 46 mm.
Subspecies: There are five subspecies, of which three occur in Canada. Subspecies varuna occurs in the Prairie Provinces and is described above; subspecies nahanni, known only from a few specimens from the Mackenzie Mountains, Northwest Territories, is darker grey above and below; subspecies cairnesi, which occurs in Yukon and the northwestern corner of the Northwest Territories, is pale ochre above with the eye-spots less contrasting.
Range: Uhler's Arctic flies in the midwestern U.S. and in the Prairie Provinces from southwestern Manitoba to the Peace River District of British Columbia; northward it flies in Yukon, western Northwest Territories, and northeastern Alaska.
Similar Species: The most similar species is the Chryxus Arctic (O. chryxus). The Alberta Arctic (O. alberta) has greater eye-spot development on the forewing, and has a sharply angled dark line on the forewing underside. [compare images]
Early Stages: The larvae are greenish tan, with grey and blackish lateral stripes. The head is brown with six darker stripes. They feed on many species of grasses (Scott, 1986).
Abundance: This is generally a common species, particularly in prairie regions.
Flight Season: From mid-May to mid-July; uhleri flies every year, but it is more common, at least in the northwest, in odd-numbered years.
Habits: In the Prairie Provinces, uhleri flies in areas of dry, sandy prairie, lightly grazed areas, and open woods, preferring hilltops and ridges where there are bunch grasses. Farther north and west it is found in clearings in forest and scrub, up to at least 3000 metres. In the north subspecies cairnesi flies in high-elevation, dry steppe-like tundra. It often lands on bare ground, where its underside coloration helps it to avoid detection. Males have the unusual habit of hovering, several metres above the ground, presumably searching for females in the grass below.
© 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.
The Toronto Entomologists' Association thanks Agriculture and Agri-Food Canada for providing the content and computer code for this web page.