The Quarren Crab Cannon was an underwater vehicle used by the Quarren Isolation League in Star Wars: Clone Wars Chapter Five.
It was similar in appearance to the Opee Sea Killer and walked on the ocean floor on ten legs. It was piloted by a group of Quarren and succeeded in destroying an Assult Ship at the Battle of Mon Calamari during the Clone Wars. It is unknown if more of these vehicles exist, but the one percent at the battle was pushed into a crevase by Kit Fisto and the Mon Calamari Knights.