Brown shyshark
Encyclopedia
The brown shyshark or plain happy, (Haploblepharus fuscus) is a species
of catshark
, family
Scyliorhinidae, endemic to the shallow, coastal waters of South Africa
from west of Cape Agulhas
to KwaZulu-Natal
. This benthic species is usually found over sandy or rocky bottoms. Measuring up to 73 cm (28.7 in) 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 lobster
s, and is oviparous with females laying pairs of egg capsules. The International Union for Conservation of Nature (IUCN) has assessed this harmless species as Near Threatened
. It is of no commercial
or recreational
interest, but its limited distribution makes its entire population vulnerable to increases in fishing pressure or habitat degradation.
in 1950, in the scientific journal
Annals and Magazine of Natural History. He chose the specific epithet fuscus, which is Latin
for "brown". The type specimen was a 57 cm (22.4 in) long adult male caught off East London, South Africa. A 2006 phylogenetic analysis
based on three mitochondrial DNA
gene
s found that the brown shyshark and the dark shyshark
(H. pictus) are sister species, and are the more derived
members of the family compared to the basal
puffadder shyshark
(H. edwardsii).
s, from the intertidal zone
to a depth of 35 m (114.8 ft). However, it has been reported from as deep as 133 m (436.4 ft). 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.
(protective third eyelid
) and a strong ridge underneath. The nostril
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
s are positioned on the upper sides of the body.
The first dorsal fin
originates well behind the pelvic fin origins, and the second originates behind the anal fin origin. The pectoral fins are moderately large, and the dorsal, pelvic, and anal fins are of similar sizes. The caudal fin 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
leaf-like dermal denticles. The coloration is a plain brown above and while below, though some individuals have a series of faint darker saddle-like markings or black or white spots.
s. 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
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. Males reach sexual maturity
at a length of 68–69 cm (26.8–27.2 in), and females at a length of 60–61 cm (23.6–24 in).
due to its small size, though it may be caught as bycatch
. It is regarded as a minor pest species by recreational angler
s and usually discarded or killed when hooked. The International Union for Conservation of Nature (IUCN) has assessed this species as Near Threatened
. Although it is locally abundant, heavy fishing occurs throughout its small range and an increase in fishery activities or pollution
could potentially affect the entire population. The brown shyshark adapts readily to captivity.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of catshark
Catshark
Catsharks are ground sharks of the family Scyliorhinidae, with over 150 known species. While they are generally known as catsharks, many species are commonly called dogfish....
, family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Scyliorhinidae, endemic to the shallow, coastal waters of South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
from west of Cape Agulhas
Cape Agulhas
Cape Agulhas is a rocky headland in the Western Cape, South Africa. It is the geographic southern tip of Africa and the official dividing point between the Atlantic and Indian oceans...
to KwaZulu-Natal
KwaZulu-Natal
KwaZulu-Natal is a province of South Africa. Prior to 1994, the territory now known as KwaZulu-Natal was made up of the province of Natal and the homeland of KwaZulu....
. This benthic species is usually found over sandy or rocky bottoms. Measuring up to 73 cm (28.7 in) 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 lobster
Lobster
Clawed lobsters comprise a family of large marine crustaceans. Highly prized as seafood, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate.Though several groups of crustaceans are known as lobsters, the clawed lobsters are most...
s, and is oviparous with females laying pairs of egg capsules. The International Union for Conservation of Nature (IUCN) has assessed this harmless species as Near Threatened
Near Threatened
Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status...
. It is of no commercial
Commercial fishing
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 pursue fish far into the ocean under adverse conditions...
or recreational
Recreational fishing
Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival....
interest, but its limited distribution makes its entire population vulnerable to increases in fishing pressure or habitat degradation.
Taxonomy and phylogeny
The brown shyshark was first described by South African ichthyologist James Leonard Brierley SmithJames Leonard Brierley Smith
James Leonard Brierley Smith, known as J.L.B. Smith 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 long extinct.-Early life:Born in Graaff Reinet, Smith was the elder of two sons of...
in 1950, in the scientific journal
Scientific journal
In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. There are thousands of scientific journals in publication, and many more have been published at various points in the past...
Annals and Magazine of Natural History. He chose the specific epithet fuscus, which is Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
for "brown". The type specimen was a 57 cm (22.4 in) long adult male caught off East London, South Africa. A 2006 phylogenetic analysis
Molecular phylogeny
Molecular phylogenetics is the analysis of hereditary molecular differences, mainly in DNA sequences, to gain information on an organism's evolutionary relationships. The result of a molecular phylogenetic analysis is expressed in a phylogenetic tree...
based on three mitochondrial DNA
Mitochondrial DNA
Mitochondrial DNA is the DNA located in organelles called mitochondria, structures within eukaryotic cells that convert the chemical energy from food into a form that cells can use, adenosine triphosphate...
gene
Gene
A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...
s found that the brown shyshark and the dark shyshark
Dark shyshark
The dark shyshark or pretty Happy is a species of catshark, family Scyliorhinidae, endemic to the temperate waters off southern Namibia and western South Africa. It is benthic in nature and inhabits shallow, inshore waters and favors rocky reefs and kelp forests...
(H. pictus) are sister species, and are the more derived
Derived
In phylogenetics, a derived trait is a trait that is present in an organism, but was absent in the last common ancestor of the group being considered. This may also refer to structures that are not present in an organism, but were present in its ancestors, i.e. traits that have undergone secondary...
members of the family compared to the basal
Basal (phylogenetics)
In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
puffadder shyshark
Puffadder shyshark
The puffadder shyshark or happy Eddie is a species of catshark, family Scyliorhinidae, endemic to the temperate waters off South Africa. This common shark is found on or near the bottom in sandy or rocky habitats, from the intertidal zone to a depth of . Typically reaching in length, the...
(H. edwardsii).
Distribution and habitat
The brown shyshark has a restricted distribution along the coast of South Africa, from the Western and Eastern Cape Provinces to southern KwaZulu-Natal Province. It is usually found close to the bottom over sandy flats or rocky reefReef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s, from the intertidal zone
Intertidal zone
The intertidal zone is the area that is above water at low tide and under water at high tide . This area can include many different types of habitats, with many types of animals like starfish, sea urchins, and some species of coral...
to a depth of 35 m (114.8 ft). However, it has been reported from as deep as 133 m (436.4 ft). 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.
Description
A small species reaching a maximum known length of 73 cm (28.7 in), 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 membraneNictitating membrane
The nictitating membrane is a transparent or translucent third eyelid present in some animals that can be drawn across the eye for protection and to moisten it while maintaining visibility. Some reptiles, birds, and sharks have a full nictitating membrane; in many mammals, there is a small...
(protective third eyelid
Eyelid
An eyelid is a thin fold of skin that covers and protects an eye. With the exception of the prepuce and the labia minora, it has the thinnest skin of the whole body. The levator palpebrae superioris muscle retracts the eyelid to "open" the eye. This can be either voluntarily or involuntarily...
) and a strong ridge underneath. The nostril
Nostril
A nostril is one of the two channels of the nose, from the point where they bifurcate to the external opening. In birds and mammals, they contain branched bones or cartilages called turbinates, whose function is to warm air on inhalation and remove moisture on exhalation...
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 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, rays, sawfish, and guitarfish. Most of these have five pairs, but a few species have 6 or 7 pairs...
s are positioned on the upper sides of the body.
The first dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
originates well behind the pelvic fin origins, and the second originates behind the anal fin origin. The pectoral fins are moderately large, and the dorsal, pelvic, and anal fins are of similar sizes. The caudal fin 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
Calcification is the process in which calcium salts build up in soft tissue, causing it to harden. Calcifications may be classified on whether there is mineral balance or not, and the location of the calcification.-Causes:...
leaf-like dermal denticles. The coloration is a plain brown above and while below, though some individuals have a series of faint darker saddle-like markings or black or white spots.
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 8 km (5 mi) from their original tagging location. This shark is known to feed on bony fishes and lobsterLobster
Clawed lobsters comprise a family of large marine crustaceans. Highly prized as seafood, lobsters are economically important, and are often one of the most profitable commodities in coastal areas they populate.Though several groups of crustaceans are known as lobsters, the clawed lobsters are most...
s. 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
Mermaid's purse
An egg case or egg capsule, colloquially known as a mermaid's purse or devil's purse, is a casing that surrounds the fertilized eggs of some sharks, skates, and chimaeras. They are among the common objects which are washed up by the sea. They are made of collagen protein strands...
s") two at a time. In captivity, the whelks
Buccinidae
Buccinidae is a very large and diverse taxonomic family of large sea snails, often known as whelks or true whelks.True whelks are mostly marine gastropod mollusks in the clade Neogastropoda...
Burnupena papyracea
Burnupena papyracea
Burnupena papyracea, common name the papery burnupena, is a species of sea snail, a marine gastropod mollusk in the family Buccinidae, the true whelks....
and B. lagenaria
Burnupena lagenaria
Burnupena lagenaria is a species of sea snail, a marine gastropod mollusk in the family Buccinidae, the true whelks....
have been documented piercing the egg cases and extracting the yolk. Males reach sexual maturity
Sexual maturity
Sexual maturity is the age or stage when an organism can reproduce. It is sometimes considered synonymous with adulthood, though the two are distinct...
at a length of 68–69 cm (26.8–27.2 in), and females at a length of 60–61 cm (23.6–24 in).
Human interactions
The brown shyshark is harmless to humans and not targeted by any commercial fisheriesCommercial fishing
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 pursue fish far into the ocean under adverse conditions...
due to its small size, though it may be caught as bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
. It is regarded as a minor pest species by recreational angler
Recreational fishing
Recreational fishing, also called sport fishing, is fishing for pleasure or competition. It can be contrasted with commercial fishing, which is fishing for profit, or subsistence fishing, which is fishing for survival....
s and usually discarded or killed when hooked. The International Union for Conservation of Nature (IUCN) has assessed this species as Near Threatened
Near Threatened
Near Threatened is a conservation status assigned to species or lower taxa that may be considered threatened with extinction in the near future, although it does not currently qualify for the threatened status...
. Although it is locally abundant, heavy fishing occurs throughout its small range and an increase in fishery activities or pollution
Pollution
Pollution is the introduction of contaminants into a natural environment that causes instability, disorder, harm or discomfort to the ecosystem i.e. physical systems or living organisms. Pollution can take the form of chemical substances or energy, such as noise, heat or light...
could potentially affect the entire population. The brown shyshark adapts readily to captivity.