Mutant X-Crab at Cabrillo Marine Aquarium



“Respect the claw” is the current motto at the Cabrillo Marine Aquarium where a mutant Dungeness crab is showing off more than just its regular two pincers. For whatever reason, this X-Man Wannabe crustacean has grown a third claw that sticks out from the back of its right claw. While an impressive appendage, this claw doesn’t function normal. It’s stiff with the pincers frozen in a V-shape at the top. However, having an extra claw could come in handy when a good swing around could knock out your enemy.

The aquarium came upon this super-clawed wonder from Martha Smith, owner and president of H.S. Seafood in San Pedro. She discovered the crab in a large batch brought in by local fishermen, and rather than send it on for a date with butter and lemon sauce, she opted to gift it to the aquarium.

So far, theories of the origin of X-Crab are plenty, with visitors and biologists weighing in on just how the heck this crab became a tri-clawed.

On the Cabrillo website:

According to Mike Schaadt, Director of CMA, there are two theories as to why a crab ends up with a third claw. Crabs have the ability to regenerate or grow back lost limbs and one theory is that “after losing a limb the regeneration mechanism of the crab went awry resulting in the unusual growth,” explained Schaadt.

Perhaps the crab might have been attacked after molting when it was weakest. “Crabs are most vulnerable just after molting because their new exoskeleton is still very delicate,” said Schaadt. “So another school of thought is that while the shell was very soft, the crab got into a fight, was injured, and while it was repairing itself, the injury recovered in a way that made the new claw.” (This phenomenon was first identified by a German scientist in the early 1900s and he officially called it bruchdreifachbildungen.)

Appropriately enough, X-Crab is now comfy in its new home, Tank 13, at the aquarium. We anticipate long lines to see his Royal Clawness…