Note: This recipe has not been verified against a documented source, or disagrees with one. Treat the materials and steps as unconfirmed.
InTheRiffle dressing
Hook Daiichi 1180, 12-20
Thread Olive Veevus 10/0
Materials
Tail Olive Z-Lon or Sparkle Yarn
Body Olive Brown Hareline Dubbing
Wing Natural Comparadun Hair
Head Olive Brown Hareline Dubbing
How to tie it
Start thread at the 75% mark and bind a sparse Antron shuck there, securing it back to above the barb; keep the shuck about half a shank long as the trailing nymphal skin.
Return the thread forward and build a slim, slightly tapered thread abdomen up to the 70% mark; a shuck-thin body sits the fly low in the film.
At the 70% mark tie in a short clump of pearl sparkle yarn pointing forward, then post it upright with a few turns at its base to form the visible flag.
Tie in a dun hackle by the stem behind the flag.
Dub a small thorax of matching fine dubbing around the base of the flag.
Wind the hackle 3-4 turns through the thorax, stacking each turn tight in front of the last so the fibers splay and sit the fly flat, then tie off.
Trim the flag to about one hook-gap tall, whip finish behind the eye, and add a pinpoint of cement.