Jutta Arctic
Oeneis jutta (Hübner, [1806])
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Diagnosis: The upperside is a dark blackish brown. Both wings have a band of yellowish to orange spots, one to four (usually three) on the forewing, occasionally expanded into a band, and usually five on the hindwing. Most of the forewing spots and up to two of the hindwing spots contain black eye-spots. Males have a diffuse diagonal black sex patch in the centre of the forewing. On the underside there are usually two forewing and one hindwing eye-spots, smaller than above but usually with white pupils. The hindwing underside is lightly mottled with dark brown and grey, and the borders are checkered with dark brown and white. There is a darker medial band that varies from distinct to almost non-existent. Wingspan: 35 to 55 mm.
Subspecies: The nominate subspecies is European; there are eight weakly differentiated subspecies in North America, of which seven occur in Canada. Subspecies ascerta, from eastern Canada west to southeastern Manitoba, is described in the Diagnosis above; subspecies terraenovae, from Newfoundland, is large with a bright-yellow upperside band; subspecies ridingiana, from southwestern Manitoba and Saskatchewan, has the yellow forewing and hindwing bands more continuous and tending to diffuse into the darker ground colour basally; subspecies harperi, from northern Manitoba and eastern Northwest Territories, has larger black eye-spots; subspecies chermocki, from western Alberta and southern British Columbia, has slightly less yellow than typical ridingiana; subspecies leussleri, from western Northwest Territories, is very dark with little yellow evident around the black spots; subspecies alaskensis, in Yukon and Alaska, is similar to ascerta, but is smaller with more translucent wings.
Range: The range of jutta extends from eastern Fennoscandia to Siberia, and from Newfoundland and Labrador to British Columbia and north through western Northwest Territories and Yukon to Alaska. It reaches into the U.S. in northern New England, the northern Great Lakes states, and the Rocky Mountain states. It is absent from Prince Edward Island, southwestern Ontario, and the Pacific and arctic coasts.
Similar Species: No other dark Oeneis has orange-bordered eye-spots.
Early Stages: The larvae are pale green with green and whitish lateral stripes and reddish hairs. The head is reddish brown or greenish, with six rows of brownish dots. They feed on sedges including Dense Cottongrass (Eriophorum spissum), Carex geyeri, and C. concinna. In captivity they eat grasses, sedges, and Jointed Rush (Juncus articulatus), but seem to prefer sedges (Scott, 1986).
Abundance: This species is often locally common.
Flight Season: Oeneis jutta flies from late May to midJune in eastern Ontario, from late June to late July at Churchill, and into August in Newfoundland and Labrador. It is biennial, flying in even years in southwest Manitoba and the west, and mainly in odd years from southeastern Manitoba eastward; at Churchill and in the Mer Bleue bog near Ottawa it flies every year.
Habits: Over most of its range jutta is found only in Black Spruce and Tamarack bogs and wet taiga and tundra, but in Alberta and British Columbia it flies in clearings and on trails in forests of Lodgepole Pine. In eastern bogs it prefers the edges of treed areas to the more open spaces; it is often seen perching on the tree trunks. When disturbed, it usually flies, very fast, either around the stand of trees or into it, almost never out into the open bog. If not too badly frightened, it will often return in a few minutes to the same perch. In Manitoba and eastern Ontario it has been observed feeding at the flowers of Labrador Tea (Ledum groenlandicum).
© 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.