The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
This specimen seems to be morphologically identical to the darker specimens of its species, but it's a very distinctly different color. I'm guessing this is a gender difference, just as I've guessed for the similar E. subvaria nymphs.
This mayfly was collected from unknown in Wisconsin on February 5th, 2004 and added to Troutnut.com by Troutnut on January 25th, 2006.