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The brown shyshark or plain happy (''Haploblepharus fuscus'') is a
species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...
of
catshark Catsharks are ground sharks of the family Scyliorhinidae. They are the largest family of sharks with around 160 species placed in 17 genera. Although they are generally known as catsharks, some species can also be called dogfish due to previous ...
, part of the
family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...
Scyliorhinidae. It is
endemic Endemism is the state of a species being found 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 found else ...
to the shallow, coastal waters of South Africa from west of
Cape Agulhas Cape Agulhas (; pt, Cabo das Agulhas , "Cape of the Needles") is a rocky headland in Western Cape, South Africa. It is the geographic southern tip of the African continent and the beginning of the dividing line between the Atlantic and Indian ...
to KwaZulu-Natal. This benthic species is usually found over sandy or rocky bottoms. Measuring up to long, the brown shyshark is stoutly built, with a broad, flattened head and rounded snout. Unlike other shysharks, the brown shyshark has a plain brown color, though some individuals have faint "saddle" markings or light or dark spots. When threatened, this shark curls into a circle with its tail over its eyes, which is the origin of the name "shyshark". It feeds on bony fishes and lobsters, and is oviparous with females laying pairs of egg capsules. The
International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of nat ...
(IUCN) has assessed this harmless species as Vulnerable. It is of no
commercial Commercial may refer to: * a dose of advertising conveyed through media (such as - for example - radio or television) ** Radio advertisement ** Television advertisement * (adjective for:) commerce, a system of voluntary exchange of products and s ...
or
recreational Recreation is an activity of leisure, leisure being discretionary time. The "need to do something for recreation" is an essential element of human biology and psychology. Recreational activities are often done for enjoyment, amusement, or pleasur ...
interest, but its limited distribution makes its entire population vulnerable to increases in fishing pressure or
habitat degradation Habitat destruction (also termed habitat loss and habitat reduction) is the process by which a natural habitat becomes incapable of supporting its native species. The organisms that previously inhabited the site are displaced or dead, thereby ...
.


Taxonomy and phylogeny

The brown shyshark was described by South African ichthyologist
James Leonard Brierley Smith James Leonard Brierley Smith (26 September 1897 – 8 January 1968) was a South African ichthyologist, organic chemist, and university professor. He was the first to identify a taxidermied fish as a coelacanth, at the time thought to be long ex ...
in a 1950 article for ''The Annals and Magazine of Natural History''. He chose the specific epithet ''fuscus'', which is
Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through the power of the ...
for "brown". The
type specimen In biology, a type is a particular specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to anchor or centralizes th ...
is a long adult male caught off
East London, South Africa East London ( xh, eMonti; af, Oos-Londen) is a city on the southeast coast of South Africa in the Buffalo City Metropolitan Municipality of the Eastern Cape province. The city lies on the Indian Ocean coast, largely between the Buffalo River ...
. A 2006
phylogenetic analysis In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...
based on three mitochondrial DNA
gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...
s found that the brown shyshark and the dark shyshark (''H. pictus'') are
sister species In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and ...
. They are the more derived members of the
genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...
relative to the basal puffadder shyshark (''H. edwardsii'').


Description

A small species reaching a maximum known length of , the dark shyshark has a stocky body and a short, broad head. The snout is blunt and dorsally flattened. The eyes are large and oval-shaped, with a rudimentary nictitating membrane (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. The human eye ...
) and a strong ridge underneath. The
nostril A nostril (or naris , plural ''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 turbi ...
s are very large, and are flanked by greatly expanded, triangular flaps of skin that reach the mouth. These nasal flaps cover a pair of deep grooves that connect the nasal excurrent (outflow) openings and the mouth. There are furrows at the corners of the mouth on both jaws. The teeth have a central cusp and a pair of smaller cusplets on the sides. The five pairs of
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 con ...
s are positioned on the upper sides of the body. The first
dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...
originates well behind the pelvic fin origins, and the second originates behind the anal fin origin. The
pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...
s are moderately large, and the dorsal, pelvic, and anal fins are of similar sizes. The
caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...
is short and broad, with a notch near the tip of the upper lobe and an indistinct lower lobe. The skin is thick and covered by 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 Ma ...
leaf-like dermal denticles. The coloration is a plain brown above and white below, though some individuals have a series of faint darker saddle-like markings or black or white spots.


Distribution and habitat

The brown shyshark has a restricted distribution along the coast of South Africa, from the
Western Western may refer to: Places *Western, Nebraska, a village in the US *Western, New York, a town in the US *Western Creek, Tasmania, a locality in Australia *Western Junction, Tasmania, a locality in Australia *Western world, countries that id ...
and
Eastern Cape Province The Eastern Cape is one of the provinces of South Africa. Its capital is Bhisho, but its two largest cities are East London and Gqeberha. The second largest province in the country (at 168,966 km2) after Northern Cape, it was formed in 199 ...
s to southern KwaZulu-Natal Province. It is usually found close to the bottom over sandy flats or 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 processes— deposition of sand, wave erosion planing down rock o ...
s, from the intertidal zone to a depth of . However, it has been reported from as deep as . The range of this species overlaps with the puffadder shyshark in the southeastern Cape region. There, the brown shyshark tends to favor shallow inshore habitats, while the puffadder shyshark inhabits deeper offshore waters.


Biology and ecology

The brown shyshark is a sedentary, bottom-dwelling species; one tag-recapture study found that recaptured sharks had moved no more than from their original tagging location. This shark is known to feed on bony fishes and lobsters. Like its relatives in the genus, it exhibits a curious response of curling into a ring with its tail covering its eyes when threatened, hence the name "shyshark". Reproduction is oviparous, with females depositing egg capsules (known as "
mermaid's purse An egg case or egg capsule, often colloquially called a mermaid's purse, is the casing that surrounds the eggs of oviparous sharks, skates and chimaeras. Egg cases typically contain one embryo, except for big skate and mottled skate egg c ...
s") two at a time. In captivity, the whelks '' Burnupena papyracea'' and '' B. lagenaria'' have been documented piercing the egg cases and extracting the
yolk Among animals which produce eggs, the yolk (; also known as the vitellus) is the nutrient-bearing portion of the egg whose primary function is to supply food for the development of the embryo. Some types of egg contain no yolk, for example ...
. Males reach
sexual maturity Sexual maturity is the capability of an organism to reproduce. In humans it might be considered synonymous with adulthood, but here puberty is the name for the process of biological sexual maturation, while adulthood is based on cultural definit ...
at a length of , and females at a length of .


Human interactions

The brown shyshark is harmless to humans and not targeted by any
commercial fisheries Commercial fishing is the activity of catching fish and other seafood for commercial profit, mostly from wild fisheries. It provides a large quantity of food to many countries around the world, but those who practice it as an industry must often p ...
due to its small size, though it may be caught as bycatch. It is regarded as a minor pest species by recreational anglers and usually discarded or killed when hooked. The
International Union for Conservation of Nature The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of nat ...
(IUCN) has assessed this species as Vulnerable. Although it is locally abundant, heavy fishing occurs throughout its small range and an increase in fishery activities or
pollution Pollution is the introduction of contaminants into the natural environment that cause adverse change. Pollution can take the form of any substance (solid, liquid, or gas) or energy (such as radioactivity, heat, sound, or light). Pollutants, the ...
could potentially affect the entire population. The brown shyshark adapts readily to captivity.


References

{{Taxonbar, from=Q901046 Brown shyshark Marine fish of South Africa Endemic fish of South Africa Brown shyshark