Polaris Fritillary (Boloria polaris) (Boisduval, 1828)

Diagnosis: This species is dull orange above with extensive dark shading at the base of the wings. The hindwings are reddish brown on the underside with a marginal row of white hourglass-shaped spots and a submarginal row of white crescents above black dots. There are irregular white markings towards the base of the wings. Wingspan: 32 to 38 mm.

Subspecies: Only the nominate subspecies occurs in North America. Some authors recognize specimens from Churchill, Manitoba, as subspecies stellata. This population is brighter orange than High Arctic populations, but colour is highly variable and other similar populations are scattered through the western Arctic.

Range: This is another holarctic fritillary, restricted to arctic areas in North America and Eurasia. It is found across northern Canada, from Alaska to Labrador. It is one of only six species of butterflies flying on Ellesmere Island. It ranges south to Butler Ridge in British Columbia and to Churchill in Manitoba.

Similar Species: Boloria polaris differs from the Freija Fritillary (B. freija) by its hourglass- rather than diamond-shaped white spots on the margin of the hindwing underside. [compare images]

Early Stages: The larvae appear to be undescribed, but have been recorded feeding on Mountain Avens (Dryas spp.) and on Bog Blueberry (Vaccinium uliginosum) in Manitoba (Klassen et al., 1989). They take two years to develop into adults.

The description of the image follows.
Polaris Fritillary (Boloria polaris polaris).
Churchill, Man. J.T. Troubridge

Abundance: The Polaris Fritillary is considered to be fairly common.

Flight Season: This fritillary flies in June and July (recorded in early August in the more southerly parts of its range, such as Manitoba and Labrador). In most of its range it flies every year, but at some locations only every second year, for example at Churchill only in odd-numbered years).

Habits: This is a purely arctic butterfly, flying low over the tundra. It has a swift, erratic flight, but often basks in the sun to get up the energy to fly.

© 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.