Boloria frigga

Distinguished from similar fritillaries by the characteristic under surface pattern: broad cinnamon forewing margin and relatively unmarked hindwing with only slight contrast between pale distal margin and cinnamon base. The straight, margin-parallel black markings on the upper surface also aid identification. Most similar to other Boloria species, but the specific wing pattern elements are diagnostic.

Above pale reddish yellow with black markings in central and marginal areas; markings are very straight and parallel with the distal margin. Forewing under surface has a broad cinnamon margin. Hindwing under surface is but little variegated, with a paler distal margin contrasting with the cinnamon basal area. Median band on under surface dusted with cinnamon and only slightly prominent, with an irregularly rhomboidal pale spot before the middle of the costa being conspicuous.

Occurs in bogs and tundra, specifically willow and sphagnum bogs. Found in Arctic and subarctic regions, typically north of 60° N in Europe. Habitats characterized by presence of larval host plants in wetland conditions.

Circumboreal distribution: Northern Europe (north of 60° N, with very local southern occurrences), Urals, Siberia, Northern Mongolia, Russian Far East, western United States and Canada. Recently recorded from Kolguev Island in Arctic Russia.

Larvae feed on Rubus chamaemorus (cloudberry), Vaccinium oxycoccos (small cranberry), and occasionally Vaccinium uliginosum (bog bilberry). In experimental conditions, larvae have been observed to accept Polygonum viviparum and Rubus fruticosus.

• Rubus chamaemorus - larval host plantprimary host
• Vaccinium oxycoccos - larval host plantprimary host
• Vaccinium uliginosum - larval host plantoccasional host
• Polygonum viviparum - experimental acceptanceaccepted in laboratory conditions, not confirmed as natural host
• Rubus fruticosus - experimental acceptanceaccepted in laboratory conditions, not confirmed as natural host

Produces one generation every two years (biennial life cycle). Specific details of egg, larval, pupal, and adult stages are not documented in available sources.

• Boloria seleneSimilar size and general fritillary appearance; distinguished by wing pattern details, particularly the more variegated under surface and different marginal banding patterns. B. selene has more prominent silver markings on hindwing underside.
• Other Boloria speciesShare general fritillary morphology and bog-dwelling habits; require careful examination of under surface wing pattern for accurate identification, particularly the cinnamon marginal band and rhomboidal spot characteristic of B. frigga.

• fritillary
• bog specialist
• circumboreal
• biennial
• Arctic

• BugGuide
• Wikipedia
• GBIF taxonomy match
• iNaturalist taxon
• NCBI Taxonomy
• Funding from ScottishPower Foundation helps to restore vital habitat to encourage thriving natural ecosystem - Buglife Blog - Buglife
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• An Evening at Silent Valley - Buglife Blog - Buglife
• The first record of Boloria frigga (Lepidoptera: Nymphalidae) on Kolguev Island, Arctic Russia