Saddle-case
Guides
Glossosomatidae
tortoise-case makers, saddle-case makers, little black caddisflies
Glossosomatidae is a family of caddisflies (order Trichoptera) containing 23 genera across three subfamilies. Larvae construct distinctive domed cases from pebbles bound with silk, giving rise to the common names "tortoise-case makers" or "saddle-case makers." The family has a worldwide distribution with particular diversity in the Americas. Larvae are primarily found in cool, fast-flowing streams where they serve as important bioindicators of water quality due to their sensitivity to pollution and long aquatic life stages.