Tail Medium blue dun hackle fibers (one shank length)
Body Stripped peacock eye quill (lacquered)
Hackle Medium blue dun hackle (3-4 turns)
How to tie it
Mount hook, start thread, and set a bunch of wood duck flank upright and divided at the 70% mark. The wings are the fly, so measure them one shank length tall.
Return thread to the bend and tie in a sparse blue dun tail one shank length long.
Tie in a single stripped, lacquered peacock quill at the bend; wrap it forward in touching turns for a crisp segmented body, stopping behind the wings.
Tie in a medium blue dun hackle and take 2 turns behind and 2 in front of the wings.
Build a small head and whip finish.
Substitutions
Body instead of Stripped peacock quill: Semperfli Quill Subs — Pre-printed quill, way more durable; Stripped hackle stem — Different banding pattern; Veevus Body Quill — Thread-based, won't break
Wing instead of Wood duck flank: Dyed mallard (lemon) — Standard wood duck sub; Gadwall flank — Similar barring
Other versions
3 more in the app: Classic Recipe, Lucian Vasies, Gregg Dressing (1940).