Boloria epithore

Distinguished from other North American Boloria species by its Pacific coastal distribution; B. selene (silver-bordered fritillary) and B. bellona (meadow fritillary) occur in overlapping or adjacent ranges but are primarily eastern or more widespread. B. epithore is generally smaller than many fritillaries. The combination of geographic location, size, and early summer flight period aids identification. Subspecific variation exists but is subtle; four subspecies are recognized based on geographic origin.

Wingspan 34–44 mm. Upperwing surfaces orange-brown with black spotting and checkered marginal patterning typical of fritillaries. Undersides of wings display silvery or pearly markings, characteristic of the genus. The overall size is smaller than many related fritillary species.

Associated with moist habitats supporting the larval host plant Viola ocellata. Occurs in forested and semi-open environments of the Pacific coastal region and western mountain ranges, from low elevations to subalpine zones.

Western North America from California northward through Oregon and Washington to British Columbia and Alberta.

Adult flight period June to July; univoltine with a single generation per year.

Larvae feed on Viola ocellata. Adult nectar sources are not specifically documented in available sources.

• Viola ocellata - larval host plantSole documented larval food plant

Complete metamorphosis with egg, larva, pupa, and adult stages. Univoltine life cycle with adults emerging in early summer. Overwintering stage not explicitly documented in available sources.

Adults may contribute to pollination of native flora. As a specialist herbivore in larval stages, links to Viola ocellata population dynamics.

Subject of ecological research on butterfly responses to land management practices, though most studies focus on congeneric species. Not a significant agricultural pest or commercially important species.

• Boloria seleneOverlaps in some western ranges; distinguished by broader North American distribution, generally larger size, and different larval host associations
• Boloria bellonaMeadow fritillary with more easterly and widespread distribution; differs in habitat preference and host plant use
• Boloria charicleaArctic and alpine fritillary with more northerly distribution; occurs at higher latitudes and elevations than B. epithore

• butterfly
• fritillary
• Pacific
• North America
• Nymphalidae
• specialist herbivore
• Viola

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Catalogue of Life
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