Hook 1XL, 1X strong nymph hook, #12-16 (tied on a #12)
Thread Black 70 denier
Materials
Bead Any (2.4mm on a #12, deliberately undersized for a sleeker look) (One)
Lead-free wire n/a (Six to eight wraps behind the bead)
Wire rib, medium or brassie Something lighter than the body, gold, silver or hot yellow (One strand)
Fox tail, long fibers (tail and body) Natural case (One medium clump, about a body length)
Fox tail underfur (thorax) Natural case (The underfur pulled from the same clump, dubbed loose and thick)
How to tie it
Slide a bead onto the hook (undersize it - 2.4mm on a #12 rather than 2.8mm, for a sleeker fly) and add six to eight wraps of lead-free wire behind it.
Start black thread behind the wire, take a few wraps over it, and run the thread back to the bend.
Tie in the wire rib just behind the weight.
Take a medium clump of fox tail fur, pull the underfur out to the side and set it aside for the thorax, then pinch the remaining long fibers and measure a tail about one body length (or a touch shorter).
Cord the thread up with a clockwise spin and lock the tail in with two tight wraps, adding a wrap under and back over the bundle so it cannot pull out on the next step.
Move the thread forward and park it about a bead-length behind the bead, then twist the tail fibers loosely together and wrap them forward as the body. Double a couple of wraps over each other toward the middle for a slight taper, then tie off.
Counter-wrap the rib forward in six or seven turns and tie it off behind the bead.
Wax the thread well and dub the reserved underfur on loosely and thickly, an inch and a half to two inches of noodle, then wrap the thorax up to the bead, tightening the noodle if it gets unwieldy.
Whip finish four or five turns right behind the bead, then rough the fly up with a brush and trim back any fibers that got too long.