Overview

The family occurs in all faunal regions. Approximately 12 genera with 400 species are known, and of those 5 genera with 19 species have been recorded from Australia.

Description

Adults small to medium sized with wing span 12-20 mm; often dark, blackish or mottled greyish brown. Ocelli present. Maxillary palps 5-segmented in both sexes, segment 2 with mesodistal brush of setae; segment 5 long, flexible. Mesoscutum without scutal warts, although sometimes with small groups of setae; scutellum usually with pair of warts or sometimes fused medially forming single setal wart. Wings elongate, ovoid, venation complete, discoidal cell closed in both wings, median cell closed only in fore wing; small hyaline areas at cross-veins and at arculus in fore wing.
Larvae slender, pale yellowish with sclerotised parts of the head and pronotum orange, posterior margin thickened, black; labrum membranous, T-shaped, anterolateral margins angular; meso- and metanota membranous. Abdominal gills and lateral fringe absent, anal papillae present; anal claws simple, without accessory hooks. Larvae live in soft, silken tubes or sack-like nets on underside of rocks in running waters. They feed on algae and fine organic particles which are swept by water currents into the larval nets and there picked up by the larva with its specialised labrum.