Large: wingspan, 70-75 mm.
The silver-washed fritillary is named after the silver streaks on the undersides of the wing. It has a rapid, swooping flight. Males are a spectacular orange brown with black patterning on the upper side of the wings. Both fore and hind wings have complex patterning which include a double row of black spots to the inside of a black scalloped wing margin. To the inside of the double row of spots there are further black markings that take the form of irregular elongate angular blotches. Males also have four black scent glands in the centre of their forewings that run along underlying main veins. The underside of the forewings reflect the colour patterning of the upper surface except for at the wing tip where the ground colouration becomes paler and the patterning a greenish grey. The underside of the hind wings do not reflect the upper side patterning but are replaced by a greenish grey ground colour interrupted by a number of irregular wavy white stripes.
IMAGES COURTESY OF STEVE SHROUD (C)
Females are similarly patterned to the males but lack the scent glands of the fore wings. Their ground colour is a duller brown.
Behaviour and life history
Caterpillars feed on common dog-violet growing in woodlands. Adult butterflies feed on the nectar of brambles.The species is most often to be seen either flying strongly along woodland edges, feeding on brambles in particular or else sunning itself on a vantage point in its territory. Males aggressively defend their territory from other males. Eggs are laid on the bark of trees in the immediate vicinity of their larval foodplant, the Common Dog Violet, Viola riviniana. The young caterpillars remain on the trucks and branches where they overwinter before descending in the spring to feed on the Common Dog Violet. The caterpillars pupate over June before the adults emerge in July
Distribution and status
The silver-washed fritillary (Argynnis paphia) is a Species of Conservation Concern in Britain. Changes in woodland management in recent years have led to the decline of this once common species. It was widespread across England and Wales, but is now found in southern and south-western England.
It is really only likely to be confused with the Comma, Polygonia c-album, but the smaller size and distinctively scalloped wings of the latter are sufficient to separate the two species.
Silver-washed fritillaries live in sunny, sheltered clearings in broadleaf woodlands. They may also use overgrown hedgerows near woodlands. Silver-washed fritillaries form discrete colonies and rarely move from one woodland to another.
Individual eggs are laid on tree trunks in crevices and moss.
The caterpillars hatch and hibernate over winter. In spring, they fall to the ground and feed on violets. The adult butterfly flies between June and August.