blue butterfly?

(1) Blue (butterfly) is the common name for any member of a group of butterflies belonging to the family Lycaenidae that also includes the coppers and hairstreaks.

(2) They are small, with wingspans seldom exceeding 5 cm and include the smallest known species of butterfly, the North American pygmy blue, which has a wingspan of about 15 mm .

(3) Although the name reflects the colour of their wings, many “blues” are in fact dark brown with a metallic blue sheen. The sexes are often very different in colour: the males brightly coloured with extensive blue scaling and the females brown or black with little trace of blue coloration