Hook - Mustad 94845 or equivalent
Thread - Black
Tail - Long partridge coming from the thorax
Wing case - White antron yarn or uni stretch
Thorax - Brown dubbing
Federation of Fly Fishers Fly Pattern Encyclopedia
Flytiers sure have a way at making things difficult
It really reminds me of Oliver Kite's "Bare Hook Nymph" that had nothing more than a copper wire built up thorax. I've dome a few of Kite's BHNs and also added a little dubbing to the copper thorax.... both wokred well for me the few times I tried them.
Here's video of Oliver Kite tying and fishing his BHN.