Edith's Checkerspot
Euphydryas editha (Boisduval, 1852)
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Diagnosis: Edith's Checkerspot is slightly smaller (wingspan: 24 to 42 mm) than the other similar checkerspots, but with a typical checkerspot brick-red, black and yellow pattern. Females can be considerably larger than males. The forewings are somewhat rounded. The yellow spots can be pale or even white. The brick-red postmedian band is fairly prominent and the red postmedial band appears to be double because the outer portion of the yellow median band (in chalcedona) is red in editha.
Subspecies: Up to 22 subspecies are currently recognized in western North America. Subspecies taylori occurs on Vancouver Island. Most specimens in British Columbia and Alberta are subspecies beani which was described from Banff, Alberta. Specimens from the Cypress Hills on the Alberta-Saskatchewan border are very close to subspecies hutchinsi, which primarily occurs farther south in Montana and Wyoming.
Range: This species is widespread in Canada in southern British Columbia and southern Alberta, but records are spotty. It is resident on southern Vancouver Island (rare and local) and in the southern interior of British Columbia. It is also found in the Rocky Mountains and the Cypress Hills of Alberta and Saskatchewan.
Similar Species: Euphydryas chalcedona has more pointed wings in males, and can be very similar in pattern. Differences are discussed under chalcedona. [compare images]
Early Stages: The larva is dark with white hairs or banded with white. The bases of the bristles are usually orange. The regular foodplant is plantain (Plantago spp.), but the larvae have also been reported on a variety of other plants including Indian paintbrush (Castilleja spp.) and lousewort (Pedicularis spp.).
Abundance: Considered a very local species in most of its range, it can be found in fair numbers where it occurs.
Flight Season: Varies depending on location and subspecies. Vancouver Island adults are on the wing in April and May, while farther east they fly in June and July and occasionally in August.
Habits: This butterfly has a wide tolerance for habitat types, but in Canada it is mostly associated with alpine meadows and rocky ridges above treeline.
Remarks: Euphydryas editha taylori, known in Canada only from southern Vancouver Island, is currently known from just two locations, and is considered endangered in Canada (Guppy et al., 1994).
© 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.
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