North American Butterflies and Moths List

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Butterflies of North America

Pacific Fritillary (Boloria epithore)
JPG -- species photo

Pacific Fritillary (Boloria epithore [W. H. Edwards])

Wing span: 1 3/8 - 1 3/4 inches (3.5 - 4.5 cm).

Identification: Tip of forewing rounded. Upperside bright orange; black markings large on basal half of wing, small on outer half. Underside orange with purple-brown markings; hindwing with postmedian row of dark circles.

Life history: Males patrol for females all day in woods and meadows. Overwintering is by fourth-stage caterpillars.

Flight: One flight from May-August.

Caterpillar hosts: Violets including Viola ocellata, V. sempervirens, and V. glabella.

Adult food: Flower nectar.

Habitat: Openings in moist forests, wet meadows, streamsides.

Range: Central British Columbia east and south to Alberta and Montana, south along Pacific Coast to central California.

Conservation: Populations in California's Santa Cruz Mountains are limited and may be in jeopardy.

The Nature Conservancy Global Rank: G5 - Demonstrably secure globally, though it may be quite rare in parts of its range, especially at the periphery.

Management needs: Inventory and monitor limited populations and propose any necessary conservation actions.


Scott, J. A. 1986. The butterflies of North America. Stanford University Press, 
     Stanford, Calif. 583 pages, 64 color plates.

Tilden, J. W. 1986. A field guide to western butterflies. Houghton-Mifflin Co., 
     Boston, Mass. 370 pages, 23 color plates.

Author: Jane M. Struttmann

Pacific Fritillary (Boloria epithore)
distribution map
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