COMMON BLUE(Polyommatus icarus)

The common blue is a small but beautiful butterfly with a slightly inappropriate name. It is neither particularly common nor invariably blue.

Males (main pictureabove) are always startlingly blue but two colour forms of the female are found in this country — in one the upper surface of the wings is brown, in the other it is blue with orange spots (inset) around the edge.

The food plant of the caterpillar is the flower, bird’s foot trefoil. This yellow-flowered plant has become less common in Ireland and grows on poor, well-drained soils with some lime.