This is a good pattern to fish during Pale Morning Dun or Pale Evening Dun hatches. It imitates the emerging duns that are breaking out of the nymphal shuck just under the surface. The term flymph refers to the "fly" or dun breaking out at the front while the nymphal form still exists on much of the pattern. Fish this imitation on an unweighted leader a few inches under the surface to rising or to feeding lies. Many more fish may be feeding under the surface on the drifting emergers to the ones that you see rising.

Shop Link: https://www.ebay.com/usr/customflies...

Website: https://allenmcgee.blogspot.com/

Books:
https://www.amazon.com/FlyFishingSo...

https://www.amazon.com/SpidersFlymph...

https://www.amazon.com/TyingFishing...