The Natal shyshark, eastern shyshark or happy chappie (''Haploblepharus kistnasamyi'') is a species of

shark Sharks are a group of elasmobranch cartilaginous fish characterized by a ribless endoskeleton, dermal denticles, five to seven gill slits on each side, and pectoral fins that are not fused to the head. Modern sharks are classified within the ...

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 ...

Pentanchidae Pentanchidae, the deepwater catsharks, is a family of sharks belonging to the order Carcharhiniformes Carcharhiniformes ( from Classical Greek ' (karcharos) 'sharp/jagged' and ' (rhinos) 'nose', plus Latin ''forme'' 'shape'), commonly known a ...

, the deepwater catsharks. It was once regarded as the "Natal" form of the

puffadder shyshark The puffadder shyshark (''Haploblepharus edwardsii''), also known as the Happy Eddie, is a species of shark belonging to the Family (biology), family Pentanchidae, the deepwater catsharks. This species is endemism, endemic to the temperate waters ...

(''H. edwardsii''). This shark 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 a small area off

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

from 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 ...

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 ...

. It is found close to the coast, from the

surf zone The surf zone or breaker zone is the nearshore part of a body of open water between the line at which the waves break and the shore. As ocean surface waves approach a shore, they interact with the bottom, wave shoaling, get taller and steeper, an ...

to a depth of , and has

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from the Ancient Greek word (), meaning "the depths". ...

habits. Reaching in length, the Natal shyshark is similar to the puffadder shyshark in appearance but has a stockier body, less flattened head, a compressed

caudal peduncle 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 only ...

, and a different color pattern. Rare and under threat from

habitat degradation Habitat destruction (also termed habitat loss or habitat reduction) occurs when a natural habitat is no longer able to support its native species. The organisms once living there have either moved elsewhere, or are dead, leading to a decrease ...

and

commercial fishing Commercial fishing is the activity of catching fish and other seafood for Commerce, commercial Profit (economics), profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice ...

, it has been assessed as Vulnerable by the

International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN) is an international organization working in the field of nature conservation and sustainable use of natural resources. Founded in 1948, IUCN has become the global authority on the stat ...

(IUCN).

Taxonomy

This species was once considered to be the "Natal" form of the

, which differed from the main "Cape" form in appearance and habitat preferences. In 2006, Brett A. Human and Leonard J.V. Compagno formally described this shark as a new species, in an article published in the

scientific journal In academic publishing, a scientific journal is a periodical publication designed to further the progress of science by disseminating new research findings to the scientific community. These journals serve as a platform for researchers, schola ...

''Zootaxa''. They named it after South African shark researcher Nat Kistnasamy, the Natal shyshark's original discoverer.

Distribution and habitat

The distribution of the Natal shyshark is restricted to the waters off the

, and possibly also the

and

Eastern Cape Province 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 ...

s of

. Its total range is estimated to encompass an area of under . A

species, it can be found in the

and on shallow rocky

reef A reef is a ridge or shoal of rock, coral, or similar relatively stable material lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic component, abiotic (non-living) processes such as deposition (geol ...

s. As opposed to the puffadder shyshark, which inhabits deeper, cooler waters in the northeastern parts of its range, in those areas the Natal shyshark occurs in warm inshore waters at a depth of .

Description

The Natal shyshark closely resembles the puffadder shyshark, but has a more robust body, a less flattened head, and a laterally compressed

. The snout is broad and rounded, with very large

nostril A nostril (or naris , : nares ) is either of the two orifices of the nose. They enable the entry and exit of air and other gasses through the nasal cavities. In birds and mammals, they contain branched bones or cartilages called turbinates ...

s and greatly expanded, triangular nasal skin flaps that reach the mouth. There are a pair of deep grooves, covered by the nasal flaps, that run from the excurrent (outflow) openings of the nostrils to the mouth. The mouth has furrows at the corners on both jaws, and contains teeth with 3–5 points. The eyes are large, with a rudimentary

nictitating membrane The nictitating membrane (from Latin '' nictare'', to blink) is a transparent or translucent third eyelid present in some animals that can be drawn across the eye from the medial canthus to protect and moisten it while maintaining vision. Most ...

(protective third

eyelid An eyelid ( ) is a thin fold of skin that covers and protects an eye. The levator palpebrae superioris muscle retracts the eyelid, exposing the cornea to the outside, giving vision. This can be either voluntarily or involuntarily. "Palpebral ...

) and a prominent ridge beneath. The five

gill slit Gill slits are individual openings to gills, i.e., multiple gill arches, which lack a single outer cover. Such gills are characteristic of cartilaginous fish such as sharks and rays, as well as deep-branching vertebrates such as lampreys. In c ...

s are positioned somewhat dorsally on the body. 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 ...

pelvic The pelvis (: pelves or pelvises) is the lower part of an anatomical trunk, between the abdomen and the thighs (sometimes also called pelvic region), together with its embedded skeleton (sometimes also called bony pelvis or pelvic skeleton). ...

, 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 are of roughly equal size. The dorsal fins are placed far back on the body, with the first originating behind the pelvic fin origins and the second originating behind the anal fin origins. The

pectoral fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column ...

s are moderately large. The short and broad

caudal 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 only ...

has a ventral notch on the upper lobe and an indistinct lower lobe. The skin is thick, bearing well-

calcified Calcification is the accumulation of calcium salts in a body tissue. It normally occurs in the formation of bone, but calcium can be deposited abnormally in soft tissue,Miller, J. D. Cardiovascular calcification: Orbicular origins. ''Nature Mat ...

leaf-shaped

dermal denticle A fish scale is a small rigid plate that grows out of the skin of a fish. The skin of most jawed fishes is covered with these protective scale (zoology), scales, which can also provide effective Underwater camouflage, camouflage through the us ...

s. The back is brown, with a distinctive pattern of H-shaped, dark brown saddles with well-defined margins, along with numerous small white dots and darker mottling between the saddles. This species attains a length of .

Biology and ecology

The Natal shyshark is rarer than the puffadder shyshark and little is known of its habits. Males are

sexually mature Sexual maturity is the capability of an organism to reproduce. In humans, it is related to both puberty and adulthood. ''Puberty'' is the biological process of sexual maturation, while ''adulthood'', the condition of being socially recognized as ...

at around long, and females at long. The shysharks are so named because they curl into a ring and cover their eyes with their tails when threatened.

Human interactions

The highly restricted range of the Natal shyshark is threatened by

from coastal development, particularly in the vicinity of

Durban Durban ( ; , from meaning "bay, lagoon") is the third-most populous city in South Africa, after Johannesburg and Cape Town, and the largest city in the Provinces of South Africa, province of KwaZulu-Natal. Situated on the east coast of South ...

where industrial and tourism sectors have undergone rapid expansion. Furthermore, the region is subject to heavy fishing pressure, in particular from the commercial

prawn Prawn is a common name for small aquatic crustaceans with an exoskeleton An exoskeleton () . is a skeleton that is on the exterior of an animal in the form of hardened integument, which both supports the body's shape and protects the intern ...

fishery Fishery can mean either the enterprise of raising or harvesting fish and other aquatic life or, more commonly, the site where such enterprise takes place ( a.k.a., fishing grounds). Commercial fisheries include wild fisheries and fish far ...

. Given its localized occurrence and presumably small population, this species has been assessed as Vulnerable by the

(IUCN).

References

{{Taxonbar, from=Q1570451 Natal shyshark Marine fish of South Africa Endemic fish of South Africa KwaZulu-Natal Critically endangered fish Critically endangered fauna of Africa Natal shyshark