You can sub out the wing case material(turkey) for a synthetic material like silly skin or scud back. I like to use the turkey because I have a lot of it. Don't be fooled by the length of the video, I do a lot of explaining for the various techniques thought the fly. Once you have it, they are a rather quick tie that's well worth it. The stripe is optional, but I strongly recommend using a grey stripe. A white stripe while disappear when wet. The technique for the legs one the fly is a great one to learn. I use it on a lot of my nymph patterns.
Fish this fly in tail outs and riffles and good moving runs. Isonychia nymphs are excellent swimmers, they are fast. Be sure to apply action to fly via rod twitches, swinging, and stripping. You can fish them dead drift and still pick up fish, after all the nymphs have to stop swimming at some point. Enjoy.
Hook-daiichi-2220-#12-#16. I like #14 best
Thread-brown 16/0 or 8/0
Tail- brown mini marabou or chickabou.
Abdomen- brown bou
Rib-black utc wire brassie
Stripe-light grey life flex.
Wing case- black section of turkey tail tip
Legs- dark partridge Thorax- peacock herl.