The giant Salmonflies of the Western mountains are legendary for their proclivity to elicit consistent dry-fly action and ferocious strikes.
This species is common in the Flathead River below Kerr Day. The river here is fairly warm with a cobble and boulder bottom with heavy periphyton at times. This species is not common elsewhere in western Montana.
This mayfly was collected from the Flathead River-lower in Montana on July 4th, 2005 and added to Troutnut.com by Bnewell on June 28th, 2011.