Round rubber legs Tan/barred rubber legs (several)
Rug/craft yarn (body) Tan and brown rug craft yarn (short lengths, alternating)
How to tie it
Debarb the hook and lay a thread base, then lash the lead dumbbell eyes firmly near the hook eye on the side that makes the fly ride point-up.
At the bend tie in the claws: two splayed pairs of cree hackle tips, a few strands of root-beer Krystal Flash, and two tan rubber legs, all flaring rearward about one shank long.
Cut short lengths of tan and brown yarn; tie them across the shank in figure-8 turns, alternating colors and packing each pair tight and back, working from the bend toward the eyes until the shank is full.
Figure-8 three pairs of barred rubber legs through the sides of the body as it is built. The extra legs are the improvement over the original.
Whip finish at the eyes and remove the fly from the vise.
Trim the yarn to a flat, oval crab carapace: flat top and bottom, rounded edges, so it sinks hook-up and lands soft.
Add a drop of cement to the eye and whip-finish wraps.