Quick Facts

Scientific name:  Polyommatus icarus

Size:  Wingspan approx 35mm

Distribution:  Found throughout the UK

Months seen:  May to October

Habitat:  Meadows, rough grassland and gardens

Food:  Nectar.  The caterpillars feed on bird's-foot trefoil.

Special features:  On sunny days you can sometimes find Common Blues feeding together in small groups.  They're the most commonly seen of all the blue butterflies.

The bright blue male is unmistakable, but the female is darker, and can have varying amounts of brown on the wings.

The outer edges of the wings are completely white, with no dark lines radiating out to the edges.  The undersides of the wings have orange patches near the outer edges, and the forewings have a dark spot about 5mm in from the body (see photo).

In southern England there can be two broods each year.  The first will be on the wing from May to June, while the second emerges from late July to September.  Further north there is normally only one brood appearing between July and August.

The green caterpillars are about 10mms long, quite flattened in appearance with a shiny black head.

Related Pages

• UK Safari Butterflies Section
• Identify other wildlife
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