These are probably 3rd instar larvae of Dicosmoecus gilvipes. The 4th instar larvae will be the round case made of sand grains. In this picture: Caddisfly Species Dicosmoecus gilvipes (October Caddis). From the Touchet River in Washington.

Caption

These are probably 3rd instar larvae of Dicosmoecus gilvipes. The 4th instar larvae will be the round case made of sand grains.
In this picture: Caddisfly Species Dicosmoecus gilvipes (October Caddis).
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