Hydrobiosidae

Definition

A family of caddisflies (order Trichoptera) comprising approximately 50 genera in two subfamilies, distributed primarily in the Southern Hemisphere. Larvae are aquatic and typically inhabit cool, fast-flowing streams and rivers, where they construct portable cases from mineral particles or plant material. The family is particularly diverse in Australia, New Zealand, and South America, reflecting a Gondwanan distribution pattern.

Etymology

From Greek hydro- (water) + bios (life) + -idae (family suffix), referring to the aquatic larval habitat.

Example

Larvae of the genus Apsilochorema (Hydrobiosidae) graze on periphyton in New Zealand mountain streams, their cases cemented from sand grains that provide ballast against current.

Related Terms

• Trichoptera
• caddisfly
• Rhyacophilidae
• Philopotamidae
• aquatic insect
• case-building
• Gondwanan distribution
• stream ecology

Usage Notes

Distinguished from the morphologically similar family Rhyacophilidae by larval case construction and adult wing venation; both families are members of the suborder Spicipalpia. The family-level classification of Hydrobiosidae has been historically unstable, with some genera formerly placed in Philopotamidae or as incertae sedis within Trichoptera.