Fine tying thread or floss for hot rib Hot orange / red floss (rib)
Superfine or custom mayfly dubbing Olive, PMD, or March Brown (1 pinch)
Deer or comparadun hair Natural / dun deer hair (small clump for wing)
Dry-fly hackle Dun or ginger dry fly hackle (1 feather)
How to tie it
Start thread mid-shank and tie in a sparse tuft of amber Zelon at the rear as a trailing shuck, about one hook-gap long, to mimic the nymphal husk the emerger is stuck in.
Bind in a length of hot orange thread or floss at the bend for the rib, then dub a slim abdomen forward over the rear half of the shank.
Spiral the hot rib forward in 4-5 evenly spaced turns and tie it off, that flash of hot color under the body is the trigger that sets this fly apart from the naturals.
Stack a small clump of deer hair and tie it in at the 65% mark as a short upright-to-forward wing tuft, tips forward over the eye; trim the butts.
Tie in a dry-fly hackle and dub a thorax up to the eye.
Take 2-3 turns of hackle through the thorax and just behind the wing, then trim a small V from the bottom so the fly sits low and hangs its abdomen into the film.
Whip finish, cement the head, and treat only the wing and hackle with floatant so the shuck and abdomen sink.