en Silver-washed fritillary
Argynnis paphia is a common and variable butterfly found over much of the Palaearctic ecozone.
Adults feed on the nectar of bramble, thistles, and knapweeds, and also on aphid honeydew. The silver-washed is a strong flier, and more mobile than other fritillaries, and, as such, can be seen gliding above the tree canopy at high speed. Its preferred habitat is thin, sunny, deciduous woodland, especially oaks, but it has been known to live in coniferous woodland.
Unusually for a butterfly, the female does not lay her eggs on the leaves or stem of the caterpillar’s food source (in this case violets), but instead one or two meters above the woodland floor in the crevices of tree bark close to clumps of violets. When the egg hatches in August, the caterpillar immediately goes into hibernation until spring. Upon awakening, it will drop to the ground and feed on violets close to the base of the tree. (source: Wikipedia)