The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
I found this female in the same area as a male with similar markings, probably of the same species.
This mayfly was collected from Mystery Creek #43 in New York on September 19th, 2006 and added to Troutnut.com by Troutnut on October 4th, 2006.