Some authors lump about 3,300 species in eight subfamilies here, but this arrangement almost certainly results in a massively paraphyletic and completely unnatural assemblage, united merely by symplesiomorphies retained from the first gelechioid moths.

In fact, most of these moths appear to be either closer to the Oecophorinae and are hence nowadays usually included in the Oecophoridae (Depressariinae, "Deuterogoniinae", Hypertrophinae, Stenomatinae and perhaps the enigmatic Aeolanthes), or constitute quite basal lineages of gelechioids, neither closely related to Elachista nor to Oecophora, and hence best treated as independent families within the Gelechioidea (Agonoxenidae, Ethmiidae).

Nonetheless, a considerable number of genera remain in the present family, and eventually it is likely that subdivisions will again be established (e.g. by raising some or all of the tribes proposed for the former Elachistinae to subfamily status).

Those include genital size and presence of digitate, adult abdomen segments without dorsal spines, absence of maxillary palpi and fronto-clypeal suture, and immobile abdominal segments in pupae and larvae.

Also possibly included is the Peruvian species Auxotricha ochrogypsa, described by Edward Meyrick in 1931 as the sole member of its genus.