The Dark Green Fritillary (Argynnis aglaja) is a butterfly of the Nymphalidae family. It is often seen, on pastures and flowery banks, and nearby areas where the preferred foodplants for the larvae, Viola canina and Viola riviniana, grow.
The Dark Green Fritillary uses violets within Bracken mosaics frequently consisting of one-third Bracken and two-thirds grass, often on the edges of suitable High Brown Fritillary habitat. Their distribution can be found on the NBN website.
References
Emmet, A.M., J. Heath et al. (Ed.), 1990. The Butterflies of Great Britain and Ireland. The Moths and Butterflies of Great Britain and Ireland Vol. 7 Part 1 (Hesperiidae to Nymphalidae). Harley Books, Colechester, UK. 370p.
Tomlinson, D. and R. Still, 2002. Britain's Butterflies. WildGuides, Old Basing, UK. 192p.