Very small moths, some with a bright metallic forewing fascia or white spotting, infrequently seen and difficult to identify as imagines, often requiring dissection. Most are more easily identified from their early stages; from the position of the ovum, the form of the mine, the appearance of the larva and the foodplant.
Their larvae are miners mostly of leaves making galleries and blotches, but some mine in the tender bark of trees and shrubs, or in buds and samaras. Nearly all leave the mine to pupate in a silken cocoon in soil, detritus, or occasionally on bark or leaves. Many species can be identified from the mine after the larva has left to pupate.