Silver-studded blue

Plebejus argus


The adult silver-studded blue Plebejus argus tends to emerge in June, and is usually on the wing until late August. It is a rare butterfly generally found in heathland habitats that have shorter, sparsely vegetated areas. It is restricted to close-knit colonies in southern England and Wales. The larvae feed on a wide variety of leguminous and ericaceous plants, with bell heather, cross-leaved heath and gorses preferred on heathlands. Black ants play a vital role in the lifecycle of this butterfly species as they tend the larva underground in their nests during spring, feeding on sugary secretions from its body. It is a rare butterfly which has suffered recent declines due to habitat fragmentation, and is a priority species under the UK BAP.

How to identify

The silver-studded blue is a small butterfly which gets its name from the light blue reflective studs found on the underside of the wings of most adults. The upper wings are blue with a dark outer rim. Similar to most other species of blue butterfly, the male has the more recognisable blue colouring whilst the female is a duller brown. This butterfly, however, is quite variable in its colouring; some subspecies have females with varying amounts of blue present on the wings. Its wingspan ranges from 29-31mm.

Where to find it

This butterfly is restricted to specific habitats in southern England and parts of Wales


When to find it

  • June
  • July
  • August

How can people help

The Wildlife Trusts manage many nature reserves for the benefit of all kinds of wildlife, including the silver-studded blue. You can help by supporting your local Trust and becoming a member; you'll find out about exciting wildlife happenings, events on your doorstep and volunteering opportunities and be helping local wildlife along the way.

Species information

Common name
Silver-studded blue
Latin name
Plebejus argus
Butterflies and moths
wingspan 29-31mm
Conservation status
UK BAP priority species