Green Clinging CrabMithrax sculptus
This small (1/2 to 3/4 inch) crab Can be found almost anywhere. The green colored carapace (the top of their exoskeleton) is covered with smooth bumps. They are a "true" crab, (they don't live in discarded snail shells). All these were found at snorkeling depths between 3 and 6 feet.