The black musselcracker (''Cymatoceps nasutus'') is a species of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Sparidae Sparidae is a family of ray-finned fishes belonging to the order Spariformes, the seabreams and porgies, although they were traditionally classified in the order Perciformes. The over 150 species are found in shallow and deep marine waters in t ...

, which includes the seabreams and porgies. This species is the only species in the

monospecific genus In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unispe ...

''Cymatoceps''. It is

endemic Endemism is the state of a species being found only in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also foun ...

to South Africa.

Taxonomy

The black musselcracker was first formally described as ''Chrysophrys nasutus'' in 1861 by the French

naturalist Natural history is a domain of inquiry involving organisms, including animals, fungi, and plants, in their natural environment, leaning more towards observational than experimental methods of study. A person who studies natural history is cal ...

Francis de Laporte de Castelnau Francis may refer to: People and characters *Pope Francis, head of the Catholic Church (2013–2025) *Francis (given name), including a list of people and fictional characters * Francis (surname) * Francis, a character played by YouTuber Boogie2 ...

with its type locality given as

Table Bay Table Bay (Afrikaans: ''Tafelbaai'') is a natural bay on the Atlantic Ocean overlooked by Cape Town and is at the northern end of the Cape Peninsula, which stretches south to the Cape of Good Hope. It was named because it is dominated by the fl ...

near

Cape Town Cape Town is the legislature, legislative capital city, capital of South Africa. It is the country's oldest city and the seat of the Parliament of South Africa. Cape Town is the country's List of municipalities in South Africa, second-largest ...

in South Africa. In 1938

James Leonard Brierley Smith James Leonard Brierley Smith (26 September 1897 – 8 January 1968) was a South African ichthyology, ichthyologist, organic chemist, and university professor. He was the first to identify a taxidermied fish as a coelacanth, at the time thought t ...

reclassified this species in the

monotypic In biology, a monotypic taxon is a taxonomic group (taxon) that contains only one immediately subordinate taxon. A monotypic species is one that does not include subspecies or smaller, infraspecific taxa. In the case of genera, the term "unisp ...

genus ''Cymatoceps''. This

taxon In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

is placed in the family Sparidae within the

order Order, ORDER or Orders may refer to: * A socio-political or established or existing order, e.g. World order, Ancien Regime, Pax Britannica * Categorization, the process in which ideas and objects are recognized, differentiated, and understood ...

Spariformes Spariformes is an order of ray-finned fishes consisting of six families within the series Percomorpha. Taxonomy Spariformes was first used as a taxonomic term in 1860 by the Dutch physician, herpetologist and ichthyologist Pieter Bleeker. Trad ...

by the 5th edition of ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

''. Some authorities classify this genus in the subfamily Sparinae, but the 5th edition of Fishes of the World does not recognise subfamilies within the Sparidae.

Etymology

The black musselcracker has the generic name ''Cymatoceps'' which is a combination of ''cymatos'', meaning "swelling" or "bump", and ''ceps'', meaning "head". This was not explained by Castelnau but it is thought to be an allusion to the large fleshy, protuberance on the snouts of the larger adults. The

specific name Specific name may refer to: * in Database management systems, a system-assigned name that is unique within a particular database In taxonomy, either of these two meanings, each with its own set of rules: * Specific name (botany), the two-part (bino ...

''nasutus'' means "large-nosed", also a reference to the large fleshy, protuberance on the snout.

Description

The black musselcracker is distinguished from other genera in the Sparidae by having scales on the area between the eyes and on the bases of the soft rayed parts of the

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage The fus ...

and

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

s. The flange on the

preoperculum This glossary of ichthyology is a list of definitions of terms and concepts used in ichthyology, the study of fishes. A B C ...

is partially covered with scales. The dorsal fin is supported by 12 spines and 10 soft rays while the anal fin is supported by 3 spines and 9 soft rays. The body is moderately deep and compressed, its

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

being between 2.3 and 2.5 times its depth. The dorsal profile of the head is gently sloping but in large adults develop a fleshy process on the snout and a hump before the eyes. The scales are ctenoid, larger below the

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelia ...

than above it. The overall colour of adults is dull dark grey with the chin and belly being bright white> The juveniles are dark greenish brown in colour on the body with irregular white mottling. This species has a maximum published

total length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured f ...

of and a maximum published weight of .

Distribution and habitat

The black musselcracker is endemic to South Africa where it is found from northern

KwaZulu-Natal KwaZulu-Natal (, also referred to as KZN) is a Provinces of South Africa, province of South Africa that was created in 1994 when the government merged the Zulu people, Zulu bantustan of KwaZulu ("Place of the Zulu" in Zulu language, Zulu) and ...

False Bay False Bay (Afrikaans: ''Valsbaai'') is a body of water in the Atlantic Ocean between the mountainous Cape Peninsula and the Hottentots Holland Mountains in the extreme south-west of South Africa. The mouth of the bay faces south and is demarc ...

. It has been reported from

Maputo Bay Maputo () is the Capital city, capital and largest city of Mozambique. Located near the southern end of the country, it is within of the borders with Eswatini and South Africa. The city has a population of 1,088,449 (as of 2017) distributed ov ...

in Mozambique but it is unknown from line or trap fisheries in

Maputo Maputo () is the Capital city, capital and largest city of Mozambique. Located near the southern end of the country, it is within of the borders with Eswatini and South Africa. The city has a population of 1,088,449 (as of 2017) distributed ov ...

. It is found at depths between and occurs in shallow rocky areas, rarely entering estuaries.

Biology

Black musselcrackers are is a solitary and have been recorded preying on a wide variety of prey, mainly

mollusc Mollusca is a phylum of protostome, protostomic invertebrate animals, whose members are known as molluscs or mollusks (). Around 76,000 extant taxon, extant species of molluscs are recognized, making it the second-largest animal phylum ...

crustacean Crustaceans (from Latin meaning: "those with shells" or "crusted ones") are invertebrate animals that constitute one group of arthropods that are traditionally a part of the subphylum Crustacea (), a large, diverse group of mainly aquatic arthrop ...

s, and

echinoderm An echinoderm () is any animal of the phylum Echinodermata (), which includes starfish, brittle stars, sea urchins, sand dollars and sea cucumbers, as well as the sessile sea lilies or "stone lilies". While bilaterally symmetrical as ...

s as adults. The adults are found on deeper topographically varied reefs in both inshore and offshore waters. The juveniles prefer shallower reefs, just below the low tide mark at depths of less than . Tagging studies have revealed that both juveniles and sub-adults are very sedentary and, that the limited data obtained on the movements of larger adults suggests that there is an easterly movement up the South African coast. Studies of the

otolith An otolith (, ' ear + , ', a stone), also called otoconium, statolith, or statoconium, is a calcium carbonate structure in the saccule or utricle (ear), utricle of the inner ear, specifically in the vestibular system of vertebrates. The saccule ...

s of this species show that it grows slowly and has a long life, with 45.5 years being the age of the oldest fish recorded. This species is thought to be a

protogynous hermaphrodite Sequential hermaphroditism (called dichogamy in botany) is one of the two types of hermaphroditism, the other type being simultaneous hermaphroditism. It occurs when the organism's sex changes at some point in its life. A sequential hermaphrodite ...

and, off the

Eastern Cape The Eastern Cape ( ; ) is one of the nine provinces of South Africa. Its capital is Bhisho, and its largest city is Gqeberha (Port Elizabeth). Due to its climate and nineteenth-century towns, it is a common location for tourists. It is also kno ...

spawning Spawn is the Egg cell, eggs and Spermatozoa, sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of freely releasing eggs and sperm into a body of water (fresh or marine); the physical act is ...

occurs between May and October. Sexually mature adults are not found in the

Western Cape The Western Cape ( ; , ) is a provinces of South Africa, province of South Africa, situated on the south-western coast of the country. It is the List of South African provinces by area, fourth largest of the nine provinces with an area of , an ...

suggests that the adults move east to the Eastern Cape and KwaZulu-Natal. The smallest females found which was reproductively active had a

fork length Fish measurement is the measuring of individual fish and various parts of their anatomies, for data used in many areas of ichthyology, including taxonomy and fishery biology. Overall length Standard length (SL) is the length of a fish measured fr ...

of and the age at which 50% of the fish are sexually mature is thought to be 10 years old. They are thought to change sex from female to male at a fork length of , around 18 years of age, and fish with fork lengths in excess of are all male.

Fisheries and conservation

The black musselcracker is a popular sport fish in South Africa. Because it is eagerly sought after, this species experiences a lot of over harvesting, which diminishes its chances of a stable population. The reason that black musselcracker is vulnerable to over harvesting is mainly because they have a slow growth rate, which means that they are most likely being harvested before they are old enough to reproduce. As a result of over harvesting the black musselcracker, there are now fishing regulations to protect this species. The primary rule is that each fisherman is allowed only one fish, minimum length of 50 centimeters, per day. Because of these new regulations, in some regions of South Africa, black musselcracker populations are on the rise.

References

External links

* * * * * {{Taxonbar, from=Q1409436 Sparidae Taxa named by François-Louis Laporte, comte de Castelnau Fish described in 1861