Poultry, Fisheries & Wildlife Sciences
Open Access

A Brief Note on Frill-Gilled Sharks

Elnaz Zareei^{* *}Correspondence: Elnaz Zareei, Department of Marine Living Resources, Manchester Metropolitan University, Manchester, United Kingdom, Email:

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Description

Chlamydoselachus anguineus is also known as a frill sharks, frill- gilled sharks, Greenland shark, scaffold shark, and silk shark. A frill shark belongs to the order Hexanchiform. Hexanchiform sharks have a single dorsal fin, either six or seven gill slits (as opposed to 5 in all other existing sharks) and no nictitating membrane (protective third eyelid). The frilled shark is currently one of only two known species of frilled shark. The South African flying shark, C. Africana, was recently discovered (2009) in southern Angola, Namibia, and South Africa. Both are very different from cow sharks in other respects and are likely to relocate to their own order Chlamydoselachiformes, in the near future.

Usually found on continental shelves and near the coast of large islands, although occasionally reported in open waters. They are mostly benthic and are found at depths of 100 to 1,300 meters. It feeds on other sharks, octopuses, and bony fish. Ovoviviparous, the size of the litter ranges from 2 to 10. It is not dangerous, but the teeth are sharp enough to cut the hands of the scientist examining its mouth. It is also used for bottom trawling and as fish meal and edible fish. Frilled sharks are common. They have been found almost all over the world, including the eastern Atlantic coast of northern Norway, the western Indian Ocean near South Africa, the western Pacific near New Zealand, and the eastern Pacific near the coast of Chile. For the last of those 80 million years, the frilled shark has scared the Bejeezus out of the water to find an animal with needle-like teeth in an open mouth in front of its head. When frill sharks are caught as bycatch in net or long line fisheries, they can be ground into fish meal and fish feed. Flying sharks are unique and fascinating members of ocean ecosystems.

Very little is known about the communication and perception of flying sharks, as they live in deep waters and are difficult to observe. Based on information from other deep-sea sharks, they are likely to use their lateral line and sense of touch to navigate the contours of the ocean floor. Deep-sea sharks are also sensitive to long-range noise or vibrations and to electrical impulses given by the animals' muscles. They also have the ability to detect changes in water pressure to differentiate them from top to bottom. In all sharks, fertilization occurs internally and takes place in the female's fallopian tubes or fallopian tubes. The male sharks have to grasp the females and maneuver her bodies so that she can insert her forceps to direct the sperm into the opening. Males and females only come together to mate.

It is a placental viviparous (ovoviviparity), in which embryos emerge from their egg capsules in the mother's uterus and feed on the yolk until birth. The gestation period for flying sharks can be up to three and a half years, the longest of all vertebrates. Between 2 and 15 hatchlings are born at the same time (an average of 6) that are between 40 and 60 cm long, and there does not appear to be a pronounced breeding season (which is to be expected as these sharks inhabit depths where there is little or no influence of seasonality). Males reach sexual maturity between 1.0 and 1.2 m in length and females between 1.3 and 1.5 m a possible mating of 15 males and 19 females has been recorded on a seamount in the Atlantic mountain range half.