Holly blue

The Holly blue has pale lilac-blue upperwings bordered with black, a margin that is narrow in males but broad in females. The underside is pale silvery blue with small black flecks and no orange spots, and the butterfly flies high around bushes and trees rather than low over grass like most other blues.

Two generations fly each year, one in spring and one in late summer. Spring females lay eggs on the flower buds of holly, while the summer brood switches almost entirely to ivy flowers, letting caterpillars track whichever host plant is in bud at the time.