[4] While there have been some recent DNA sequence-based studies of Palaearctic species[5][6] there is need for a satisfactory modern global phylogenetic framework for the subfamilies of Gracillariidae.

These generally small (wingspan 5–20 mm) moths are leaf miners as caterpillars,[7] which can provide a useful means of identification, especially if the hostplant is known.

Early instars have a flattened head and body, modified mandibles, and lack functional spinnerets or legs; these feed on sap.

[8][9] Later instars are cylindrical with round heads, and have chewing mouthparts, legs and functional spinnerets; these feed on plant tissue.

[6] A recent DNA sequencing study mainly of Palaearctic species has shown that the burst of evolutionary adaptive radiation occurred long after that of the larval hostplants, rather than demonstrating a tight coevolutionary process.

[2] Lithocolletinae Phyllocnistinae Marmarinae Oecophyllembiinae Acrocercopinae Gracillariinae Parornichinae Callicercopinae Ornixolinae Gracillariidae phylogeny has been revised in 2017 and is now containing eight subfamilies:[13] Unplaced species