Alternate Title

Cheliped Asymmetry in the Stone Crab, Menippe mercenaria, with Notes on Claw Reversal and Regeneration


Stone crabs (Menippe mercenaria) were reared in the laboratory to determine natural handedness. Claws of feral juvenile crabs were autotomized to test for reversal and to determine stridulatory pattern sequences. All crabs less than 4 mm carapace width were right-handed (side bearing the crusher claw). Eighty-eight percent of juvenile crabs with autotomized crushers showed signs of handedness reversal after the first regenerative molt. Stridulatory sequences indicated that a normal pattern was attained after two regenerative molts. Dockside claw surveys and trap sampling programs involving several Florida stone crab populations reveal an approximate 80:20 right:left-handed ratio in adult crabs through largest sizes trapped. This indicates that adults do not reverse as readily as juveniles.