Adonis blue

Adonis blue

Adonis blue ©Colin Williams

Adonis blue

Scientific name: Polyommatus bellargus
The rare Adonis blue can be spotted on sunny chalk grasslands throughout summer. Males are a dazzling sky-blue in colour, while females are duller brown.

Species information


Wingspan: 3.0-4.0cm

Conservation status

Protected in the UK under the Wildlife and Countryside Act, 1981.

When to see

May to September


The Adonis blue is the rarest of the blue butterflies in the UK. It is found on sunny, south-facing grassland that is rich in herbs. It doesn't travel far, so colonies can become isolated and vulnerable to extinction if their habitat is disturbed. This species has two broods per year, so adults can be seen from mid-May until the end of June, and then from early August until the end of September. Both caterpillars and adults feed on Horseshoe Vetch.

How to identify

Male Adonis blues are a vivid, sky-blue or turquoise colour. There are fine black lines on the wings that extend into the white fringe. Females are generally brown, though this can vary and some may be quite blue.


Found in southern England.

Did you know?

The caterpillars of the Adonis blue are always found with ants! The ants protect the caterpillars in return for a sugary substance that they produce.

How people can help

The Wildlife Trusts manage many grassland habitats sympathetically for the benefit of all kinds of butterflies, including the Adonis blue. Careful grazing with traditional breeds, hay-cutting at the right time and scrub clearance are just some of the ways grasslands are kept in good condition - supporting invertebrates and, in turn, the larger animals that prey on them. By volunteering for your local Trust you can help too, and you'll make new friends and learn new skills along the way.