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 numerous mature nymphs and one flying adult of this species at the end of July in a small stream at 5,200 feet elevation in the Wenatchee Mountains of Washington.
Although Kogotus and Rickeri nymphs may be difficult or impossible to tell apart, I captured an adult Kogotus nonus specimen in the air on the same day as several of these nymphs, and they are likely the same species.
Described by Needham, J.G. & Claassen, P.W. (1925) A Monograph of the Plecoptera or Stoneflies of America North of Mexico. The Thomas Say Foundation II, 1–397.