Male Common Blue Butterfly, Polyommatus icarus. Devon, UK
Wingspan up to 35mms, found throughout the UK between May to October the caterpillars feed on bird’s-foot trefoil and it can often be seen in meadows, rough grassland and gardens. On sunny days you can sometimes find these butterflies feeding together in small colonies. It’s 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.
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, and have a shiny black head.