This is the first of it's family I've seen, collected from a tiny, fishless stream in the Cascades. The three species of this genus all live in the Northwest and are predators that primarily eat stonefly nymphs Merritt R.W., Cummins, K.W., and Berg, M.B. (2019).
This genus can get incredibly abundant especially below dams.This specimen shows the two sclerotized bars needed to identify it to genus. These usually curl up like this one when preserved.