Based on the limited research I did, the pattern (poly yarn body) was often used on the Deschutes as a stonefly (in these colors I'd guess a salmonfly). Charlie Craven has a version http://www.charliesflyboxinc.com/fly...m?parentID=149 without the front hackle that he uses as a caddis emerger. I tied it with the spun deer hair body just for fun (and because I knew someone on another forum who has an aversion to foam would give me grief).

Regards,
Scott