The caterpillars of this small blue butterfly feed on holly and ivy.

Statistics
Wingspan: 20mm.

Physical description
A very small blue butterfly with a few small black spots across its wings and a black border that is more pronounced in females. The undersides of the wings are pale blue. The body is blue and covered in long hairs. The antennae are black with small white stripes along their length. This butterfly appears slightly silvery when in flight.

The caterpillar is small and light green.

Distribution
Holly blues are widespread throughout Britain and Europe. They are also found in Asia, North Africa and North America.

Habitat
They inhabit woodlands and gardens, particularly where there is both holly and ivy.

Diet
The spring brood of caterpillars feed on holly, whereas the summer brood feed on ivy. Caterpillars also feed on gorse and bramble. Adults tend to feed on the flowers of ivy and holly.

Reproduction
This species has two broods in the summer. The first, in the spring, feed on holly and when they become adults and have mated they lay their eggs on ivy plants. The ivy brood overwinter as crysalids and emerge in the spring to mate and lay their eggs on holly.

Conservation status
Holly blue populations tend to fluctuate between the years and have been very scarce in some years. They are currently abundant and are not listed as endangered on IUCN Red List 2000.