Ecnomidae

Definition

A family of caddisflies (order Trichoptera) comprising approximately 9 genera and 375 described species. Ecnomidae are small to minute trichopterans with reduced wing venation and larvae that typically inhabit running waters, where they construct portable cases from sand grains or small particles. The family has a predominantly Southern Hemisphere distribution with highest diversity in Australia, New Zealand, and South America, though some species occur in the Oriental and Palearctic regions. Adults are often collected at light traps and can be distinguished from related families by characteristic wing-coupling structures and genitalic morphology.

Etymology

From Greek 'oiknomos' (household manager or steward), possibly alluding to larval case-building behavior; family name established by Ulmer in 1903.

Example

Larvae of the Australian genus Ecnomus construct curved, tusk-shaped cases from sand grains cemented with silk, and are commonly found in the hygropetric zone of waterfalls and cascades.

Related Terms

• Trichoptera
• caddisfly
• Integripalpia
• Ecnomus
• larval case
• hygropetric zone
• wing coupling
• genitalic morphology
• Southern Hemisphere biogeography

Usage Notes

The family was formerly treated as a subfamily within Psychomyiidae or as part of a broader 'Psychomyioidea' grouping, but molecular and morphological studies support its recognition as a distinct family. Ecnomidae are sometimes referred to as 'tusked caddisflies' in popular literature due to the distinctive larval cases of some genera. Specialists distinguish Ecnomidae from the related Psychomyiidae by features of the male genitalia and larval case architecture. The family is not to be confused with similarly named taxa in other groups; the spelling 'Ecnomidae' is unique to Trichoptera.