This is the commonest British hairstreak, but it is seldom seen, as it lives in the canopy of oak trees and only rarely descends to paths and clearings. It is almost certainly greatly under recorded.
Where to look
Look high in the canopy of mature Oak trees, preferably using binoculars. Most frequent in south Cumbria but there are scattered colonies on the Solway plain, west Cumbria and lower Eden valley
When to look
Late July to end of August. This species rarely flies in overcast conditions