The famous nocturnal Hex hatch of the Midwest (and a few other lucky locations) stirs to the surface mythically large brown trout that only touch streamers for the rest of the year.
I found this dun floating on the surface at night while I mucked around in the shallows collecting nymphs. I suspect he may have been prompted to emerge by the stress of my disturbance.
This mayfly was collected from the Namekagon River in Wisconsin on May 22nd, 2004 and added to Troutnut.com by Troutnut on January 25th, 2006.