Clam crackers
| Clam crackers | ||||||||||||
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Shellcrackers ( Cymatoceps nasutus ) |
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Cymatoceps | ||||||||||||
| Smith , 1938 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Cymatoceps nasutus | ||||||||||||
| ( Castelnau , 1861) |
The musselcracker ( Cymatoceps nasutus ) is a marine fish from the monotypic genus Cymatoceps within the sea bream family . It is characterized by a bulging head, a protruding, fleshy nose and a strong jaw.
features
With a length of 1.5 meters and a weight of 38 kilograms, the musselcracker is one of the largest representatives of the sea bream. He can live to be 45 years old. The adult fish have a large, fleshy nose and a heavy, bulbous head with thick lips. There are four protruding incisors in the upper jaw and six in the lower jaw. In each jaw there are two rows of rounded molars. The body is deep and robust. However, the body shape varies with size and age. The body color also changes with age. Most adult individuals are soot-gray to blue-black. The growing fish are lighter everywhere and can have two or more dark, wide horizontal stripes on the flanks. The body color of juvenile fish is generally greenish-brown with white spots. 61 to 65 rows with hard, thick scales are arranged along the lateral line organ. The scales on the underside are significantly larger. The single dorsal fin consists of twelve spines and ten rays. The anal fin consists of three spines and eight rays. The caudal fin is slightly forked. The number of gill traps on the first gill arch is ten.
distribution
The distribution area of the mussel cracker includes the tropical and temperate Atlantic and the Indian Ocean. It occurs on the coast of Maputo in Mozambique and along the coastal waters of South Africa from KwaZulu-Natal to Cape Town .
Way of life
The musselcracker lives individually and inhabits both shallow and deep, coastal rock reefs down to a depth of 100 meters. The juvenile fish prefer rocky tunnels in the Wadden Sea as growth areas, while the adult fish are found in deeper waters. Occasionally larger individuals migrate over the shallow reefs and look for food near the coast. The diet consists of crabs, sea cucumbers, lobsters and other hard-shelled animals. The prey is held in place with the conical teeth before it is cracked with the powerful jaws and molars.
The females of the mussel crackers reach sexual maturity at a length of 55 centimeters or at the age of about ten years. At the age of 18 they undergo sex reassignment to males.
literature
- Rudy Van der Elst & Peter Borchert: A Guide to the Common Sea Fishes of Southern Africa . Struik, 1997, ISBN 9781868253944
Web links
- Shellcrackers on Fishbase.org (English)
- Black musselcracker - Cymatoceps nasutus (description and photo)