The Ecnomidae have a Gondwanan distribution, except one genus, which also is present in Oriental and Palearctic regions.

The adult is a mostly small to medium-sized caddisfly with a wingspan of 6–18 mm (0.24–0.71 in), with dull grayish-brown mottled wings.

The Ecnomidae larval stage, like most trichoptera larvae, is spent completely in fresh water.

Permanent ponds and lakes or slower-flowing waters is suitable habitat for Ecnomidae larvae.

All Ecnomidae genera are restricted to the Southern Hemisphere except the genus Ecnomus, which is widely distributed.