Callinectes marginatus, known as the "sharptooth swimcrab" or "marbled swimcrab", is a species of swimming crab in the genus Callinectes

Callinectes

Callinectes is a genus of crabs, containing 16 species, including the Atlantic blue crab, C. sapidus:*Callinectes affinis Fausto, 1980*Callinectes amnicola *Callinectes arcuatus Ordway, 1863...

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Description

Its carapace bears nine spines behind each eye, the last of which is around twice the length of the previous one, making the whole carapace

Carapace

A carapace is a dorsal section of the exoskeleton or shell in a number of animal groups, including arthropods such as crustaceans and arachnids, as well as vertebrates such as turtles and tortoises. In turtles and tortoises, the underside is called the plastron.-Crustaceans:In crustaceans, the...

 around 10 centimetres (3.9 in) wide.

Distribution and ecology

Although the name Callinectes marginatus was used by Mary Rathbun

Mary Rathbun

Mary J. Rathbun was an American zoologist who specialized in crustaceans. She worked at the Smithsonian Institution, often unaided, from 1884 until her death...

 and others to also cover animals now referred to the species C. larvatus and C. diacanthus, C. marginatus is now used only for a species found from the Cape Verde Islands

Cape Verde

The Republic of Cape Verde is an island country, spanning an archipelago of 10 islands located in the central Atlantic Ocean, 570 kilometres off the coast of Western Africa...

 and Nouadhibou

Nouadhibou

Nouadhibou is the second largest city in Mauritania and serves as a major commercial centre. The city itself has about 75,000 inhabitants expanding to over 90,000 in the larger metropolitan area. It is situated on a 40-mile peninsula or headland called Ras Nouadhibou, Cap Blanc, or Cabo Blanco, of...

, Mauritania

Mauritania

Mauritania is a country in the Maghreb and West Africa. It is bordered by the Atlantic Ocean in the west, by Western Sahara in the north, by Algeria in the northeast, by Mali in the east and southeast, and by Senegal in the southwest...

 to Angola

Angola

Angola, officially the Republic of Angola , is a country in south-central Africa bordered by Namibia on the south, the Democratic Republic of the Congo on the north, and Zambia on the east; its west coast is on the Atlantic Ocean with Luanda as its capital city...

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C. marginatus appears to be entirely marine, unlike some of its congeners, although there are records from the estuaries of the Congo River

Congo River

The Congo River is a river in Africa, and is the deepest river in the world, with measured depths in excess of . It is the second largest river in the world by volume of water discharged, though it has only one-fifth the volume of the world's largest river, the Amazon...

 and the Hwini River. The crabs dig holes around 30 cm (11.8 in) wide in mudflat

Mudflat

Mudflats or mud flats, also known as tidal flats, are coastal wetlands that form when mud is deposited by tides or rivers. They are found in sheltered areas such as bays, bayous, lagoons, and estuaries. Mudflats may be viewed geologically as exposed layers of bay mud, resulting from deposition of...

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