Dark Green Fritillary (Argynnis aglaja)
This very large butterfly is bright orange with black patterns on the upperwing, and a green sheen to the underwing. Important food plants for the caterpillars are those in the violet family. It is fast flying but its size makes it easy to spot. They occur on flower-rich grasslands.
Best spot = Bryn tip LNR
For more information see the Butterfly Conservation Dark green fritillary page.