Dwarf gulper shark

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Dwarf gulper shark
Centrophorus atromarginatus.jpg
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Subdivision: Selachimorpha
Order: Squaliformes
Family: Centrophoridae
Genus: Centrophorus
Species:
C. atromarginatus
Binomial name
Centrophorus atromarginatus
Garman, 1913
Centrophorus atromarginatus distmap.png
Range of dwarf gulper shark (in blue)

The dwarf gulper shark (Centrophorus atromarginatus) is a dogfish of the family Centrophoridae found in the Indo-West Pacific oceans, from the Gulf of Aden, Japan, Taiwan, and northern Papua New Guinea, living and feeding at dephts exciding 656 ft (m), marine, deep-water dogfish most commonly found between 328 ft and 3937 ft (100-1200 meters)

Contents

Biology

The maximum total length recorded for the gulper shark is 5 ft (150 cm). Gulper shark pups average from 1 to 1.4 ft (30-42 cm) total length at birth. Precise details of the size, age, and growth, such as size at maturity for the gulper shark, are currently unknown. The gulper shark is a slim, relatively long dogfish with two dorsal fins bearing long grooved spines. The second dorsal fin is shorter than the first, and its base is about three-fourths the length of the first dorsal fin. The distance from the first and second dorsal fins is equal to the distance from the tip of the snout to the axil of the pectoral fin. The color of the gulper shark is olive-grey to grey-brown or sandy grey to brown dorsally and lighter ventrally with no obvious markings in adults; juveniles may be lighter and may have dusky tips on the dorsal and caudal fins.

Squalene: a nutritional compound

As a Squaliform, Centrophorus atromarginatus has high amounts of Squalene in its liver, and it is fished for this resource. Squalane is a useful chemical for human health, healthsqualene. Is extracted from dwarf gulper shark and industrially converted to squalane with hydrogen addition. On the other hand, the consumption of its meat is quite limited because high amount of ammonia gradually builds up as the freshness decrease. Using shark muscle for healthy food is important, but not many studies have looked into it beyond making gelatin. We can break down the proteins in shark muscle using enzymes called proteases to get useful parts called peptides. These peptides can help lower high blood pressure by stopping an enzyme called ACE. [2]

High blood pressure is a big problem worldwide, and stopping ACE is one way to manage it. By using different proteases from things like fish, seaweed, shellfish, and milk, we can make shark muscle peptides that lower blood pressure. This not only makes use of parts of the shark that would otherwise be wasted but also lets us make the peptides in different ways to make them work better. Also, we can isolate and study the specific peptides that work best to lower blood pressure. This helps us make better foods that can help with high blood pressure and other health problems.

The family Centrophoridae includes the gulper shark, Centophorus granulosus. Bloch and Schneider first identified the gulper shark as Squalus granulosus in 1801. Centophorus granulosus is the current accepted scientific name for the gulper shark. The Greek words kentron, which means "thorn," and pherein, which means "to bear," are the source of the genus name Centrophorus. These terms refer to the spines that all dogfish have on their first and second dorsal fins. In the eastern Atlantic, gulper sharks are caught using a range of techniques, such as bottom trawls, hook and line, and pelagic trawls. This species is targeted by some deepwater longline fisheries, while it is occasionally caught as bycatch.

A little gulper shark specimen was found in the Norwegian Sea near northern Norway, making it the farthest north this species has been recorded in the eastern North Atlantic Ocean. Based on its physical characteristics, it seems closely related to the Australian species called Centrophorus zeehaani. When scientists analyzed the DNA from the mitochondrial cytochrome oxidase subunit I (coI) gene, they found that the DNA barcoding suggested that C. uyato and C. zeehaani are likely the same species. [3]

In addition, there have been recent revisions to the classification of species within the Centrophorus genus. Currently, four species are recognized in the eastern North Atlantic Ocean: C. granulosus, the lowfin gulper shark (Centrophorus lusitanicus), the leafscale gulper shark (Centrophorus squamosus), and the little gulper shark (Centrophorus uyato). While there is some uncertainty about the validity of the species name C. uyato, it is recommended by White et al. (2013) to use this name for the smaller species of the genus, which was previously often referred to as C. granulosus.

Centrophorus uyato can grow up to 110 cm in total length, with males reaching maturity at 80 cm (White et al., 2013).

This study highlights the northernmost sighting of C. uyato in the eastern North Atlantic Ocean to date. It also provides a summary of the taxonomic characteristics of the four species found in the area and compares their mitochondrial cytochrome oxidase subunit I (coI) sequences.

On 22 February 2011, a commercial longliner named Atlantic deployed a 6000 m longline at depths ranging from 233 to 557 m near the continental shelf off northern Norway (coordinates: 68° 48·5′ N; 12° 54·0′ E). The longline, which consisted of 4000 hooks (size 12/0) arranged in a semi-circle, was baited with Atlantic saury and squid. The line was left to soak from 0150 to 1800 hours GMT, targeting tusk and haddock. The specimen was frozen upon collection, then thawed for a closer look after being brought to land. It has been stored at the University Museum of Bergen in Norway under the accession number ZMUB 21441. To identify the species morphologically, the methods outlined by White et al. (2013) were followed. During examination, a total of 88 morphometric measurements, as defined by Compagno (1984), were recorded for the specimen.


Related Research Articles

The Centrophoridae are a family of squaliform sharks. The family contains just two genera and about 15 species. They are sometimes called gulper sharks, but this is also the name of a specific species in the family, Centrophorus granulosus. These are generally deepwater fish. While some, such as the gulper shark C. granulosus, are found worldwide and fished commercially, others are uncommon and little-known. Their usual prey is other fish; some are known to feed on squid, octopus, and shrimp. Some species live on the bottom (benthic), while others are pelagic. They are ovoviviparous, with the female retaining the egg-cases in her body until they hatch.

<span class="mw-page-title-main">Dusky smooth-hound</span> Species of shark

The dusky smooth-hound, also called the smooth dogfish or the dog shark, is a species of houndshark in the family Triakidae. This shark is an olive grey or brown in color, and may have shades of yellow or grayish white. Females live to 16 years and males have a lifespan of 10 years. M. canis was the first shark recognised to have viral infections.

<span class="mw-page-title-main">Porbeagle</span> Species of shark (Lamna nasus)

The porbeagle or porbeagle shark is a species of mackerel shark in the family Lamnidae, distributed widely in the cold and temperate marine waters of the North Atlantic and Southern Hemisphere. In the North Pacific, its ecological equivalent is the closely related salmon shark (L. ditropis). It typically reaches 2.5 m (8.2 ft) in length and a weight of 135 kg (298 lb); North Atlantic sharks grow larger than Southern Hemisphere sharks and differ in coloration and aspects of life history. Gray above and white below, the porbeagle has a very stout midsection that tapers towards the long, pointed snout and the narrow base of the tail. It has large pectoral and first dorsal fins, tiny pelvic, second dorsal, and anal fins, and a crescent-shaped caudal fin. The most distinctive features of this species are its three-cusped teeth, the white blotch at the aft base of its first dorsal fin, and the two pairs of lateral keels on its tail.

Centrophorus is a genus of squaliform sharks. These deep-water sharks, found in temperate and tropical oceans throughout the world, are characterized by grey or brown bodies, large green eyes, and spines on both dorsal fins. These spines give them their name, from Greek κεντρον, kentron meaning "thorn" and φέρειν, pherein meaning "to bear".

<span class="mw-page-title-main">Dumb gulper shark</span> Species of shark

The dumb gulper shark is a rare and endangered deepwater dogfish, found along the east coast of Australia and in isolated spots north and west of New Zealand. It is also known as the dumb shark, Harrison's deep-sea dogfish, or Harrison's dogfish.

<span class="mw-page-title-main">Lowfin gulper shark</span> Species of shark

The lowfin gulper shark is a large deepwater dogfish in the family Centrophoridae.

<span class="mw-page-title-main">Smallfin gulper shark</span> Species of shark

The smallfin gulper shark or endeavour dogfish, is a medium-sized deepwater dogfish in the family Centrophoridae.

<span class="mw-page-title-main">Leafscale gulper shark</span> Species of shark

The leafscale gulper shark is a dogfish of the family Centrophoridae. C. squamosus is reported to have a lifespan of approximately 70 years, based on otolith ring counts. It was the first described species in the genus Centrophorus, which now contains 13 species.

<span class="mw-page-title-main">Mosaic gulper shark</span> Species of shark

The mosaic gulper shark is a small rare deepwater dogfish, found in the Pacific Ocean around Honshū, Japan and the Hawaiian Islands at depths between 260 and 728 m. It is one of 13 described species in the genus Centrophorus.

<span class="mw-page-title-main">Little gulper shark</span> Species of shark

The little gulper shark is a small, deepwater dogfish of the family Centrophoridae.

<span class="mw-page-title-main">Gulper shark</span> Species of shark

The gulper shark is a long and slender dogfish usually about three feet in length generally found in deep, murky waters all around the world. It is a light grayish brown, paler ventrally, with a long snout and large greenish eyes. This deep water shark has two dorsal fins with long, grooved spines and the second dorsal fin smaller than the first. Its upper teeth are blade-like and lower have finely serrated edges. This tertiary consumer feeds on mainly fish such as bony fish, but also cephalopods such as squid and other invertebrates like crustaceans. The gulper shark is currently an endangered species mainly because of exploitation by humans and their abnormally long gestation period and low fecundity, preventing their population from recovering. Because of the depth of their habitat, they are considered little to no threat to humans.

<span class="mw-page-title-main">Arrowhead dogfish</span> Species of shark

The arrowhead dogfish is a small little known deepwater dogfish of the family Centrophoridae.

<span class="mw-page-title-main">Blackfin gulper shark</span> Species of shark

The blackfin gulper shark is a dogfish of the family Centrophoridae in the Northwest Pacific.

<span class="mw-page-title-main">Portuguese dogfish</span> Species of shark

The Portuguese dogfish or Portuguese shark, is a species of sleeper shark of the family Somniosidae. This globally distributed species has been reported down to a depth of 3,675 m (12,057 ft), making it the deepest-living shark known. It inhabits lower continental slopes and abyssal plains, usually staying near the bottom. Stocky and dark brown in color, the Portuguese dogfish can be distinguished from similar-looking species by the small spines in front of its dorsal fins. Its dermal denticles are also unusual, resembling the scales of a bony fish. This species typically reaches 0.9–1 m (3.0–3.3 ft) in length; sharks in the Mediterranean Sea are much smaller and have distinct depth and food preferences.

<span class="mw-page-title-main">Largetooth cookiecutter shark</span> Species of shark

The largetooth cookiecutter shark is a rare species of squaliform shark in the family Dalatiidae, reported from depths of 60–200 m (200–660 ft) at scattered locations in the Atlantic and Pacific Oceans. As its common name suggests, it is similar in appearance to the cookiecutter shark but has much larger lower teeth. This species reaches a maximum known length of 42 cm (17 in). The largetooth cookiecutter shark feeds by gouging out chunks of flesh from larger animals, including bony fishes, sharks, and marine mammals, and is able to take larger bites than I. brasiliensis. Little is known of its life history; it is thought to be a weaker swimmer than I. brasiliensis, and is presumably aplacental viviparous like the rest of its family. This shark is an infrequent bycatch of commercial trawl and longline fisheries, but is not thought to be much threatened by these activities.

<span class="mw-page-title-main">Velvet belly lanternshark</span> Species of shark

The velvet belly lanternshark is a species of dogfish shark in the family Etmopteridae. One of the most common deepwater sharks in the northeastern Atlantic Ocean, the velvet belly is found from Iceland and Norway to Gabon and South Africa at a depth of 20–2,490 m (66–8,169 ft). A small shark generally no more than 45 cm (18 in) long, the velvet belly is so named because its black underside is abruptly distinct from the brown coloration on the rest of its body. The body of this species is fairly stout, with a moderately long snout and tail, and very small gill slits. Like other lanternsharks, the velvet belly is bioluminescent, with light-emitting photophores forming a species-specific pattern over its flanks and abdomen. The ventral photophores are thought to function in counter-illumination, which camouflages the shark against predators and prey. The bioluminescent flank markings may play a role in intraspecific communication.

<span class="mw-page-title-main">Seychelles gulper shark</span> Species of fish

The Seychelles gulper shark is a species of fish in the family Centrophoridae found in Alphonse island in Seychelles. This species is distinguished by having large tip of snout to first dorsal distance of 34% TL; first dorsal fin high ; second dorsal fin base long ; long snout ; uniformly grey with tip and the trailing edge of dorsal fins blackish. It is one of 11 described species in the genus Centrophorus.

<span class="mw-page-title-main">Southern dogfish</span> Species of shark

The southern dogfish is a species of shark in the family Centrophoridae. It was described in 2008 along with the western gulper shark, and belongs to genus Centrophorus. It is mainly found in the Indian and Pacific ocean, but they are distributed in other oceans as well. As a result, it is one of the more recent and elusive types of shark to date.

References

  1. Rigby, C.L.; Ebert, D.A.; Herman, K. (2020). "Centrophorus atromarginatus". IUCN Red List of Threatened Species . 2020: e.T161384A124474968. doi: 10.2305/IUCN.UK.2020-3.RLTS.T161384A124474968.en . Retrieved 18 November 2021.
  2. Ikeda, Asami; Ichino, Hayato; Kiguchiya, Saori; Komatsu, Masaharu; Shiozaki, Kazuhiro (2015). "Evaluation and Identification of Potent Angiotensin-I Converting Enzyme Inhibitory Peptide Derived from Dwarf Gulper Shark (Centrophorus atromarginatus)". Journal of Food Processing and Preservation. 39 (2). Journal of Food Processing and information: 107–115. doi:10.1111/jfpp.12210 . Retrieved 13 April 2024.
  3. Wienerroither, R.M.; Bjelland, O.; Junge, C. (2015). "Northernmost record of the little gulper shark Centrophorus uyato in the north-eastern Atlantic Ocean, with taxonomical notes on Centrophorus zeehaan". Journal of Fish Biology. 86 (2): 834–844. Bibcode:2015JFBio..86..834W. doi:10.1111/jfb.12602. PMID   25605421 . Retrieved 13 April 2024.