THE XERCES SOCIETY FOR INVERTEBRATE CONSERVATION

Aquatic Invertebrates in Pacific Northwest Freshwater Wetlands
An Identification Guide and Educational Resource

Dryopidae are unique among aquatic insects in that their larvae are primarily terrestrial, but the adults are aquatic. The genus Helichus is the most likely to be encountered in the Northwest; the other genera of western North America are primarily found in the Southwest. Dryopidae prefer streams and rivers, and may be found rarely in swamps or ponds.

Adult dryopids may be mistaken for elmids, but the Dryopidae are generally larger and have short, thick, comb-like antennae that are often tucked under their heads.

Size: small
Identifying feature(s): comb-like antennae
Habitat: still water to stream riffles
Tolerance to pollutants: tolerant