The Adelidae or fairy longhorn moths are a family of monotrysian moths in the lepidopteran infraorder Heteroneura. Most species have at least partially metallic patterns coloration and are diurnal, sometimes swarming around the tips of branches with an undulating flight. Others are crepuscular and have a drab coloration. Fairy longhorn moths have a wingspan of 4–28 millimeters, and males often have especially long antennae, 1–3 times as long as the forewing.