The mono loop at the bend of the hook is used to prevent the tail from fouling around the hook. Interesting thought about it enhancing the snapping action. On size 6 & 8, I don't think it is necessary since the tail is not long enough to foul.
The fly rides hook point up because of the weighted eyes on top of the shank.
Generally, at the bend there is an orange egg sac. this can be a small clump of maribou or glo-bug yarn. The body is made similar to a Merkin, e.g. alternating bands of Aunt Lydia rug yarn.
It is an interesting fly and a must in the Keys. It is said that it is used to depict, toad fish, mantis shrimp and crabs.
When I get a chance, I'll post a photo.