The Lycaenidae are the second-largest family of butterflies, with about 6000 species worldwide, whose members are also called gossamer-winged butterflies. They constitute about 40% of the known butterfly species.

The family is traditionally divided into the subfamilies of the blues (Polyommatinae), the coppers (Lycaeninae), the hairstreaks (Theclinae) and the harvesters (Miletinae); others include the Lipteninae, Liphyrinae, Curetinae and Poritiinae.