metalmark, (subfamily Riodininae), any of a group of small, principally South American insects in the gossamer-winged butterfly family, Lycaenidae (order Lepidoptera), that are named for characteristic metallic wing markings. Metalmarks are difficult to recognize because many species mimic other lepidopterans and have evolved almost every combination of colour and wing shape.
Most males possess reduced front legs, whereas females have functional ones. Most of the broad, flat, and usually hairy larvae feed on ragwort and thistles.