Bead-chain or small dumbbell eyes (mount to ride hook-up) Black mono eyes small (1 pair)
Rabbit or marabou (antennae/claws) Rust/brown rabbit or marabou (small bunches)
Grizzly hackle tips or rubber (claws) Barred brown grizzly hackle tips or rubber (2)
Crawdad / hare's-ear dubbing (body) Rusty brown (for body)
Palmer hackle Brown hackle (1 feather)
Thin Skin or Scud Back (carapace) Brown thin skin mottled (1 strip)
Fine wire rib Copper wire (1 strand)
How to tie it
Lash the eyes on top of the shank near the eye so the fly rides hook-point-up (crayfish flee backward, so the head is tied at the hook bend).
At the hook bend (the crayfish's head end), tie in a small tuft of rust fibers for antennae and two splayed grizzly tips or rubber legs for claws, kept short and mobile.
Tie in the Thin Skin carapace strip and a length of copper wire, then dub a fat, shaggy body forward toward the eyes.
Palmer a brown hackle through the body for legs, then stroke the fibers down.
Pull the Thin Skin over the back as a carapace and rib it down with 5 open turns of copper wire, segmenting the shell; break off the wire.
Build a small thread tail behind the eyes to suggest the crayfish's fanned tail, then whip finish and coat the carapace with a thin layer of UV resin or cement.