THE XERCES SOCIETY FOR INVERTEBRATE CONSERVATION

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

Psychodid adults resemble tiny moths. These small hairy flies commonly show up in bathrooms, as some species make their home in sink drains and other areas that connect to sewer systems. In these locations, the larvae can play an important role in processing bacteria and fungi. Psychodid larvae are also found in water that accumulates in tree holes.

Psychodid larvae are quite diverse. They are small with well defined heads; cylindrical or slightly flattened bodies that lack prolegs; and their body segments are often subdivided two or three times. These subdivisions give the larvae the appearance of having 20 or more segments, and often have dark plates dorsally.

Genera found in still or slack waters include Philosepedon, which are found in wetlands, pools and lake edges; and Telmatoscopus, which are present in wetlands, lake or stream edges, or tree holes.