Atlantic weasel shark

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Atlantic weasel shark
Paragaleus pectoralis X-ray.jpg
X-ray image of Paragaleus pectoralis
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Superorder: Selachimorpha
Order: Carcharhiniformes
Family: Hemigaleidae
Genus: Paragaleus
Species:
P. pectoralis
Binomial name
Paragaleus pectoralis
(Garman, 1906)
Paragaleus pectoralis distmap.png
Synonyms
  • Hemigaleus pectoralis(Garman, 1906)
  • Paragaleus gruveli(Budker, 1935)

The Atlantic weasel shark (Paragaleus pectoralis) is a weasel shark of the family Hemigaleidae, found in the eastern Atlantic Ocean. Also known as the little tiger shark, it is the only species of the genus Paragaleus to have been recorded off the western coast of Africa. [2] It is one of four species of small sharks within the carcharhinoid genus Paragaleus, including Paragaleus leucolomatus (whitetip weasel shark), Paragaleus tengi (straight-tooth weasel shark), and Paragaleus randalli (slender weasel shark). [3] It also one of eight species within the weasel shark family, Hemigaleidae. It is currently considered by the International Union for Conservation of Nature (IUCN) as Endangered.

Contents

Appearance and morphology

This particular species of weasel shark is slender with a moderately long snout, large eyes, and a short and small mouth. [4] It has small, serrated upper teeth and erect-cusped lower teeth. [4] It is identified by its light grey color and longitudinal yellow stripes on the sides of the body. [3] [4] Of its two dorsal fins, the first fin, located in front of the pelvic fins, is larger than the second. [5] In addition, it has asymmetric caudal fins with precaudal pits. [5]

Range and habitat

Common inshore and offshore along continental shelves of the eastern Atlantic, it can be found close to land in the surf zone from Mauritania to Angola. [4] It is also commonly found in tropical to warm-temperate waters around the Cape Verde Islands, reaching depths of 100 m. [6] It has been found in the following countries: Angola, Benin, Cameroon, Cape Verde, Congo, Côte d'Ivoire, Equatorial Guinea, Gabon, Gambia, Ghana, Guinea, Guinea-Bissau, Liberia, Mauritania, Nigeria, Senegal, Sierra Leone, and Togo. However, its presence has also been recorded on one occasion off the east coast of the United States, close to New England. [7]

Size and life cycle

One of the smaller species of shark, the largest recorded adult Atlantic weasel shark measured only 138 cm (4.53 ft) and weighed 11 kg (24 lb), [2] which is believed to be their maximum size. Feeding primarily on cephalopods, including squid and octopuses, [6] it display slow growth rates as well as late maturity in their lifespan. [4] This shark is considered as a specialist feeder, preying on small bony fishes including soles and sardines in addition to cephalopods. [6] Mating season for this species occurs from March to May, while offspring are released from May to June. [2] These sharks are viviparous and give birth to live young which develop inside the parent's body with a yolk-sac placenta. [4] [6] It gives birth to 1 to 4 pups per litter, averaging in 47 cm in length. [6] While males mature at 80 cm in length, females may mature between 75 cm and 90 cm in length. [2]

Relationship with humans

Atlantic weasel sharks are a common catch of small commercial fisheries in the eastern Atlantic and are mostly captured during spring and summer in fishing sites along the coast of Senegal. [6] [2] Atlantic weasel sharks are caught using a variety of fishing gear, such as longlines, hook and line, gillnets, and bottom trawls. [3] As such, their meat is used either fresh or dried for human consumption and also processed into fishmeal. [6] At the moment, there are no conservation efforts in place to protect this species because catch levels are neither quantified nor monitored. [6]

Related Research Articles

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The sharpnose sevengill shark, also known as one-finned shark, perlon shark, sevengill cow shark, sharpsnouted sevengill or slender sevengill, is a species of shark in the family Hexanchidae, and the only living species in the genus Heptranchias. Found almost circumglobally in deep water, it is one of the few species of sharks with seven pairs of gill slits as opposed to the usual five. The other shark species with seven gill slits is the broadnose sevengill shark. Though small, this shark is an active, voracious predator of invertebrates and fish. When caught, this species is notably defensive and will attempt to bite. It is of minor commercial importance.

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Barbeled houndshark Species of shark

The barbeled houndshark is a species of ground shark and the only member of the family Leptochariidae. This demersal species is found in the coastal waters of the eastern Atlantic Ocean from Mauritania to Angola, at depths of 10–75 m (33–246 ft). It favors muddy habitats, particularly around river mouths. The barbeled houndshark is characterized by a very slender body, nasal barbels, long furrows at the corners of the mouth, and sexually dimorphic teeth. Its maximum known length is 82 cm (32 in).

Australian weasel shark Species of shark

The Australian weasel shark is an uncommon species of ground shark in the family Hemigaleidae. It inhabits shallow waters off northern Australia to a depth of 170 m (560 ft); smaller sharks frequent sand and seagrass habitat and shift to coral reefs as they grow older. A slim, drab species reaching a length of 1.1 m (3.6 ft), it has sickle-shaped fins with dark tips on the second dorsal fin and caudal fin upper lobe. Its upper teeth are broad with strong serrations only on the trailing edge. The lateral line along each side is prominent and exhibits a downward curve below the second dorsal fin.

Sicklefin weasel shark Species of shark

The sicklefin weasel shark is an uncommon species of ground shark in the family Hemigaleidae. It is native to southern India, southern China, and parts of Southeast Asia, living in shallow waters down to a depth of 170 m (560 ft). This lightly built shark is characterized by its very short mouth, broad upper teeth with serrations only on the trailing edge, and strongly sickle-shaped fins with obvious white tips on the two dorsal fins. It is light grey or bronze in colour, often with small white blotches on its sides; it reaches a maximum known length of 1.1 m (3.6 ft).

Straight-tooth weasel shark Species of shark

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Sailfin roughshark Species of shark

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Sharptooth houndshark Species of shark

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Atlantic sawtail catshark Species of shark

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Blackmouth lanternshark Species of shark

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<i>Lutjanus agennes</i> Species of fish

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Senegal jack Species of fish

The Senegal jack, also known as the African jack, is a species of large marine fish classified in the jack family Carangidae. The species is distributed through the tropical waters of the eastern Atlantic Ocean, ranging along the west African coast from Angola in the south to Mauritania in the north. It can be distinguished from co-occurring relatives by its longer dorsal fin lobe, as well as a host of other anatomical features. The Senegal jack grows to a known maximum length of 1 m. It is a coastal species, known to live semi-pelagically, inhabiting both the sea floor and surface waters to depths of around 200 m. The Senegal jack is a predatory species, taking fish, crabs and shrimps as its main prey items. The species reaches sexual maturity at 21 cm in females and 24 cm in males, with spawning occurring in two periods; February to April and September to November. The species is of minor importance to fisheries, and is not discriminated from other jacks in catch statistics. It is taken by trawls, seines and hook and line, and sold fresh or preserved.

Blackchin guitarfish Species of cartilaginous fish

The blackchin guitarfish is a species of cartilaginous fish in the family Rhinobatidae. It is native to the eastern Atlantic Ocean and the Mediterranean Sea. It is a bottom-dwelling fish feeding on crustaceans, other invertebrates and fish. The females give birth to live young. Its lifestyle makes it vulnerable to trawling and other fishing methods, populations seem to be declining and it is subject to intensive fishing pressure, with its fins being sold into the Asian market. The International Union for Conservation of Nature has assessed its conservation status as being "critically endangered".

Torpedo mackayana, commonly known as the ringed torpedo, Western African torpedo, West African torpedo ray, McKay electric ray, or McKay's torpedo ray, is an electric ray species in the family Torpedinidae, which lives in shallow waters on the western coast of Africa. Characterized by rounded spiracles and white and brown spots, females grow to 35–50 centimetres (14–20 in) and males to 31.5–38.2 centimetres (12.4–15.0 in).

African forktail snapper

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References

  1. Jabado, R.W., Chartrain, E., De Bruyne, G., Derrick, D., Dia, M., Diop, M., Doherty, P., Ducrocq, M., Leurs, G.H.L., Metcalfe, K., Pires, J.D., Ratão, S., Seidu, I., Soares, A.-L., Tamo, A., VanderWright, W.J. & Williams, A.B. (2021). Paragaleus pectoralis. The IUCN Red List of Threatened Species https://www.iucnredlist.org/species/161707/124531152
  2. 1 2 3 4 5 C. Capape, Y Diatta, M Diop, C Reynaud, O Guelorget (2005). “New data on the reproductive biology of the Atlantic weasel shark, Paragaleus pectoralis (Chondrichthyes: Hemigaleidae) from the coast of Senegal (eastern tropical Atlantic)”. International Journal of Ichthyology29(4):363-371
  3. 1 2 3 "L Compagno, E Krupp, K Carpenter - Fauna of Saudi Arabia, 1996".
  4. 1 2 3 4 5 6 "Froese, R. and D. Pauly. Editors. 2017.FishBase. World Wide Web electronic publication. www.fishbase.org, ( 10/2017 )".
  5. 1 2 "Atlantic Weasel Sharks". MarineBio.org. Archived from the original on 2018-02-26.
  6. 1 2 3 4 5 6 7 8 Bates, H. 2009. Paragaleus pectoralis. The IUCN Red List of Threatened Species 2009: e.T161707A5485308. https://dx.doi.org/10.2305/IUCN.UK.2009-2.RLTS.T161707A5485308.en. Downloaded on 25 February 2018.
  7. "Paragaleus pectoralis :: Florida Museum of Natural History". www.floridamuseum.ufl.edu. Retrieved 2018-02-25.