The Adelidae, or fairy longhorn moths, are a family of over 300 species of small, day-flying moths. Males have antennae 2–3 times the length of their forewings. The family was described by Charles Théophile Bruand d’Uzelle in 1851 and belongs to the monotrysian lineage within Incurvarioidea. These moths are absent from New Zealand; about 13 species occur in North America.

Adults fly in daylight, often in swarms near tree branches. Their wings show metallic colors (gold, copper, or silver) and are held roof-like at rest. They chew solid food rather than drink nectar. Larvae build portable cases from silk and plant material, feeding on leaf litter or living plants.

The family includes two main subfamilies, Adelinae and Nematopogoninae, with many genera unplaced. Common genera are Adela (including A. reaumurella), Ceromitia (51 species, mostly tropical), and Nemophora (including N. degeerella). Recent studies have added new species, especially from the Neotropics.