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.
Earlfishman on May 19, 2007May 19th, 2007, 7:59 am EDT
Based on the head pattern, this larvae might be Polycentropus sp. or Neureclipsis sp., I find myself leaning towards the former but I've been wrong before. It's hard to tell for sure without close up photos of anal claws and legs. You can tell it isn't a Rhyacophilid because there isn't a sclerite on top of ab seg number 9.