They are most common in the Palearctic, and rare in sub-Saharan Africa, South America, and Australia; consequently, they probably originated (like most or all other Gelechioidea families) in northern Eurasia.

When they emerge to feed externally, they usually construct a protective silken case, discarded and built anew as they grow and molt.

The bagworm moths (Psychidae), which also belong to the primitive Ditrysia (although to superfamily Tineoidea, not Gelechioidea), build similar cases as larvae.

The Blastobasidae, Momphidae (mompha moths), Pterolonchidae, and Symmocidae have formerly been included in the Coleophoridae as subfamilies, but are more often considered separate families today.

[3] Genera of case-bearers at least provisionally accepted by recent authors include:[4] Data related to Coleophoridae at Wikispecies See also Gelechioidea Talk page for comparison of some approaches to gelechioid systematics and taxonomy.