Body Yellow textreme silk thread (Textreme silk thread)
Ribbing Brown uni (Uni 6/0 or 8/0 thread)
Tail Pardo Flor de Escoba or Pardo Medio (Coq de Leon barbs)
Hackle Natural hackle (CDC barbs saved from used feathers, in a dubbing loop)
How to tie it
Start white GSP thread at the eye and wind back to the bend. White GSP is chosen specifically so it does not tint the silk once wet, a coloured tying thread bleeds through and changes the body colour you worked for.
Tie in a sparse tail of Coq de Leon Pardo Flor de Escoba or Pardo Medio, around a shank long.
Tie in the brown Uni 6/0 for the rib, then wind the yellow Textreme silk forward in touching turns to the 65% mark. Silk darkens and goes translucent when wet, which is exactly the effect this old pattern is built around.
Rib forward with four or five open turns of brown thread and tie off. Thin dark segmentation over a bright silk body.
Build a dubbing loop and load it with the leftover CDC barbs stripped from feathers used on other flies. Spin it tight, wind it as a collar at the 75% mark, and whip finish a small head.
Decide density at this step: pack the loop full and the fly fishes as a dry; keep it sparse and it settles into the film or just under, which is used on slow rivers where fish inspect everything before eating.