Heath Fritillary

Appearance

:"See glossary for terms used"
Heath Fritillaries have a wing-span of 39–47 mm. The upperside is predominantly dark brown and orange-brown, with the orange-brown spots delineated by dark brown; there is a white fringe to the wings through which the dark brown extends. The upperside of the body is a similar dark brown to the colour on the wing, and the base of both wings is dark brown. The underside shows bands of red and white, again with each vein dark brown and each colour delineated by dark brown. The pattern of white spots at the base of the hindwing is diagnostic for identification.

Naming

Up to eight subspecies are recognized in Europe:
⤷ "M. a. athalia" – from the Atlantic coast to the Bosporus, excluding the ranges of the following subspecies
⤷ "M. a. norvegica" Aurivillius 1888 – Fennoscandia
⤷ "M. a. celadussa" Frühstorfer 1910 – northern Iberia and the Sierra Nevada, southern France, southern Switzerland, Italy
⟶ *The transitional zone between subspecies "athalia" and "celadussa" is broad—up to 150 km in places
⤷ "M. a. dictynnoides" – south-west Europe?
⤷ "M. a. licufuga" – south-east Europe
⤷ "M. a. reticulata" Higgins 1955 – Altai
⤷ "M. a. baikalensis" – southern Siberia to Amur?
⤷ "M. a. hyperborea" Dubatolov 1997 – Magadan, Kamchatka

Many forms and subspecies of "M. a. athalia" have been described, but are best regarded as "ecological variants" and intermediates in clinal variation. Bulgaria has f. "boris" Frühstorfer, with heavier marginal borders, alongside the typical nominate form.

In central Sweden and Finland, "M. a. norvegica" f. "lachares" Frühstorfer has finer black markings; transitional forms between f. "lachares" and typical "M. a. norvegica" occur in southern Sweden.

In Portugal and north-west Spain, "M. a. celadussa" f. "biedermanni" Querci is larger than typical "M. a. celadussa", with finer black lines in the outer half of the wing, but a thicker discal line; transitional forms occur in central west Spain. In Sierra Nevada, f. "nevadensis" Verity is golden-yellow with fine black markings. In "southern" Europe, f. "tenuicola" Verity occurs in late broods—it is small and its black markings reduced.

Status

Heath Fritillary is not listed on the IUCN Red List, suggesting that globally it is not considered threatened.

In the UK, however, the species was "considered to be the most endangered British butterfly" after a nationwide survey in 1980 found only 31 surviving colonies. Consequently, it was given protection under the Wildlife and Countryside Act 1981. Despite subsequent widespread efforts to conserve and manage the species' habitats, it has continued to decline: distribution has declined 25% since the 1970s, and abundance-wise it declined by 46% in the 10 years 1995–2004. Woodland sites in Kent and Essex are actively managed for the conservation of this species. It has been a "high priority" species in the UK Biodiversity Action Plan since 1995 and has its own "Species Action Plan".

Heath Fritillary is also on the "Red List" in Germany.

However, the species is considered of "least concern" on a European scale.

Habitat

Within Europe, the Heath Fritillary occupies a diversity of grassy, flowery habitats—dry or damp, upland or lowland, with or without shrubs or trees, including woodland clearings and heathland.

More specifically, in England, this species occupies three distinct habitats:
⤷ Unimproved grassland with abundant short or sparse swards of Ribwort Plantain or Germander Speedwell on stony soils – sometimes in the form of abandoned hay-meadows
⤷ Sheltered heathland with Common Cow-wheat scattered among Bilberry-dominated vegetation – valleys with mineral soils
⤷ Coppiced woodland with Common Cow-wheat on acid soils.

In France, this species also occurs on unimproved hay-meadows and pastures.