About Fabriciana adippe vorax (Butler, 1871)
This taxon is the subspecies Fabriciana adippe vorax (Butler, 1871), a type of high brown fritillary butterfly. On average, the high brown fritillary has a wingspan of around 65 mm. Its upper wings are orange with black markings, while the undersides are a duller orange with white and brown markings. In flight, it is very difficult to distinguish from the dark green fritillary, which shares many of the same markings. Males and females share many physical features. Larvae are brown with a single longitudinal white stripe running the full length of their body. Their bodies are covered in brown spikes that help camouflage them from predators as they move among dead fern fronds. According to Seitz's description of A. adippe L. (= berecynthia Poda, cydippe L.) (69d): this butterfly is usually larger than the previous species, Argynnis alexandra Ménetries, 1832, with more obtuse wings. In females, the outer margin of the forewing is quite straight, and the outer margin of the hindwing is feebly undulate. Males are easily recognized by thickened hairy streaks located on the branches of the forewing median vein. On the underside of the wings, silver spots are much larger than those of niobe, especially the marginal spots, which are much longer and broader. This butterfly has many subspecies distributed across temperate regions of Europe, Asia, and Africa. Northern Europe has experienced a severe decline in high brown fritillary populations, but the butterfly remains relatively abundant in other parts of Europe. As of 2015, the high brown fritillary was the most threatened butterfly species in Britain. In Great Britain, persistent populations only remain in four areas: the Morecambe Bay Limestone hills, the Glamorgan Brackenlands, Dartmoor, and Exmoor. High brown fritillary populations are supported by two main habitats: bracken and limestone outcrops. Bracken habitats occur across the butterfly's full geographic range, while limestone outcrop habitats are specific to Great Britain. High brown fritillaries in woodland habitats have been most severely affected by habitat loss. These butterflies relied heavily on coppicing, a land management technique that has nearly disappeared from the British countryside. The reduction of coppicing, combined with replanting and new forest growth, has severely limited the areas where the fritillary can thrive, as bracken habitats become rarer. Within existing bracken habitats, population loss is driven by either excessively dense bracken growth, or trampling of the butterfly's associated flora by grazing animals.
