The Common Blue is the UK's most widespread blue butterfly. Males display vibrant blue wings with a white fringe, while females are typically brown with orange spots and a hint of blue near the body. Interestingly, the blue coloration is not due to pigment but results from microscopic scales on the wings that reflect light, creating a shimmering effect.

Common Blues inhabit a variety of sunny, grassy environments across the UK, including meadows, coastal dunes, woodland clearings, and even urban gardens. They are active from May to October, with two generations per year in southern regions and one in the north.

Adult butterflies feed on nectar from flowers such as clovers, buttercups, and daisies. Their caterpillars primarily consume plants in the pea family, especially Common Bird’s-foot-trefoil (Lotus corniculatus), which is crucial for their development