Cuata Swim Crab, Callinectes arcuatus

Cuata Swim Crab, Callinectes arcuatus. Crab provided by the commercial fishermen of the greater Los Cabos area, Baja California Sur, October 2009. Size: 4.0 cm (1.6 inches).

General information:  The Cuata Swim Crab, Callinectes arcuatus, is a common member of the Portunidae or Swimming Crab Family, which are known in Mexico as Jaibas. The Cuata Swim Crab is known in Mexico as Jaiba Cuata. Globally the family has thirteen Genera of which sixteen individual species are found in Mexican waters. The commercially important Blue Crab, Callinectes sapidus, is a member of this family.

Identification:  The Cuata Swim Crab is a decapod with ten limbs. Swim Crabs are colorful and active crabs that are among the few crabs that are swift and agile swimmers. They swim sideways utilizing their paddle-like fifth pair of (dactyl) legs that rotate like propeller blades when they swim, However, they are essentially bottom dwellers. They have a streamlined profile that allows for rapid swimming and long pincers armed with sharp spines to snag food. The Cuata Swim Crab has a uniquely shaped shell with two long spines at the edges that point upwards that are included in a series of nine teeth on each side of the shell that run from the middle of the shell to the eyes. The shells are covered with fine granules. A key to identification is the presence of two high triangularly shaped teeth with two smaller similarly shaped teeth in the middle of the shell between the eyes. The claws are unique with a series of teeth and two spines on each which are pictured below. The male crab (pictured above) has a narrow triangular abdomen while the female and a much wider and more oval abdomen. The Cuata Swim Crab reach a maximum size of 13 cm (5.1 inches) They can be confused with the Cortez Swim Crab, Callinectes bellicosus (smooth shell with pale legs).

Habitat and Range: The Cuata Swim Crab reside in all Mexican waters of the Pacific Ocean and extend south to the west coast of South America reaching the northern coast of Chile. They are found over sand and mud bottoms within estuaries, mangrove swamps and tidal flats inter-tidally at depths up to 46 m (150 feet). They can often be confused with the Cortez Swim Crab, Callinectes bellicosus (smooth shell with pale legs).

Diet: The Cuata Swim Crab consumes clams, fish, snails, worms and other small crustaceans.

Conservation Status: From a conservation perspective the Cuata Swim Crab has not been formally evaluated. However, they have a very wide distribution and are common in some regions and should be consider to be of Least Concern.  Their long term viability can be threatened by overfishing as the larger females are selectively removed from populations.