Metacarcinus gracilis (formerly Cancer gracilis) or commonly the graceful rock crab or slender crab, is one of only two members of the genus Metacarcinus whose chelae (claws) are white tipped, the other crab being M. magister (Dungeness crab). M. gracilis has been caught from Alaska to Bahía Magdelena, Baja California. Although M. gracilis is only found in the Pacific Ocean, it has cousins in the Atlantic Ocean.