The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
Both the genus ID (Merritt & Cummins) and species ID (Flint 1984) are pretty confident for this larva, a nice example of a common western caddisfly. It was by far the most abundant insect in my kicknet sample on this trip, and many of the rocks in the fast riffle where I sampled had dozens of these larvae clinging on.
This caddisfly was collected from the Dosewallips River in Washington on July 6th, 2020 and added to Troutnut.com by Troutnut on July 12th, 2020.