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 would not like to have to match this hatch. These are the smallest mayflies I have ever seen. I used to think Caenis was the smallest adult mayfly in the west but these guys are about 4mm long. The male eyes are two toned, brown above and olive below. The abdomen is dark brown interspersed with light brown. The abdomen is clear for the anterior 2/3rd and the remainder is white. The tails are twice as long as the insect. There is only one pair of wings.
This mayfly was collected from the Touchet River in Washington on July 27th, 2011 and added to Troutnut.com by Bnewell on July 27th, 2011.