any member of the approximately 300 species in the cosmopolitan family Nepticulidae (sometimes called Stigmellidae), containing some of the smallest members of the order Lepidoptera. Most have long and pointed wings generally covered with scales and spinelike hairs; the wingspan is from 3 to 6 mm (¹/₈ to ²/₅ inch).

Most nepticulid larvae are leaf miners, although some species produce galls on plants. Pupation occurs either inside larval galleries or within thick, silken cocoons constructed in rubbish piles or in loose soil.