This simple fly, the Crackleback. There are times and situations when this fly will out fish most other flies. It is generally fished as a dry in a long float, and then tugged underwater and stripped from the swing, all the way back. Seems most strikes are taken underwater in the strip back. Great for fast, relatively shallow water. The fly was originated by one of the folks at Feather Craft in St. Louis, if memory serves.
This is a size 14, but larger ones are perhaps even more effective.
The body color can be altered, but yellow seems to be the standard.
Order of tie
1. several strands of peacock which will be pulled over the hackle as the last step.
2. one size 14 brown hackle feather
3. yellow body of nearly any material. Can be turkey biot, etc.
Hope not too boring, but some might be interested.