The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
This one was preserved in ethanol and partially dissected, so it doesn't have its natural wild coloration, and it's missing some appendages. I'm posting it for identification purposes.
This mayfly was collected from Mystery Creek #186 in Alaska on September 4th, 2015 and added to Troutnut.com by Troutnut on October 27th, 2015.