Glossosomatidae

Definition

A family of caddisflies (order Trichoptera) characterized by larvae that construct distinctive portable, dome-shaped cases from sand grains or small rock fragments cemented together with silk. The family comprises 23 genera arranged in three subfamilies, with approximately 76 species in six genera recorded from North America alone. Larvae are typically found in cool, flowing waters where they graze on periphyton.

Etymology

Example

Glossosomatid larvae can be distinguished from other caddisfly families by their tortoise-shell-like cases, which they carry as they crawl along stream substrates; genera such as Glossosoma and Agapetus are common in North American mountain streams.

Related Terms

• Trichoptera
• caddisfly
• case-building
• periphyton
• lotic
• benthic macroinvertebrate
• Agapetus
• Glossosoma

Usage Notes

The family is sometimes referred to informally as "tortoise-case caddisflies" due to the characteristic case morphology. Identification to genus often requires examination of larval case structure and adult genitalia; the family is ecologically important as a component of stream biomonitoring indices.