Douglas-fir (Pseudotsuga) is a host plant common to many species of the family, particularly of the genus Chionodes, which as a result is more diverse in North America than usual for Gelechioidea.

While these figures are certainly outdated, due to the many revisions to superfamily Gelechioidea and new descriptions of twirler moths, they still serve to show the enormous biodiversity contained in this important family.

Being abundant, fecund plant-eaters, many species are agricultural pests, including: The voracious habits of their larvae make twirler moths suitable for biological control of invasive plants.

Compared to the other massively diverse Gelechioidea families – Coleophoridae (case-bearers) and Oecophoridae (concealer moths) – the systematics of the Gelechiidae are far less contentious.

[3][4][5][6][7] Of the subfamilies traditionally accepted for the Gelechiidae, only three were maintained for some time pending further information; at least one other, the Physoptilinae, were suggested to also be valid.