Helicopsyche borealis (Snail-shell Caddisfly)

These unique caddisflies build helical cases out of small cobble and sand. They are very tiny and can be found clinging to the underside of rocks or nestled into the substrate.

 

These caddisflies were found at a single site in the gravel under a rock below a riffle. Their tiny size makes them easily overlooked and I likely missed them at other sites.

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