The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
This one doesn't have the protruding mouthparts typical of Cinygmula, but I think it's just an oddball individual.
This mayfly was collected from Swauk Creek in Washington on June 13th, 2022 and added to Troutnut.com by Troutnut on June 14th, 2022.