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.
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.
This stonefly was collected from Mystery Creek #199 in Washington on July 28th, 2019 and added to Troutnut.com by Troutnut on July 30th, 2019.