Australian angel shark
| Australian angel shark | ||||||||||||
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Australian angel shark at the Bicheno Dive Center, Tasmania |
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| Squatina australis | ||||||||||||
| Regan , 1906 |
The Australian angel shark ( Squatina australis ) is a ground-dwelling shark found in the southern coastal area of Australia and around Tasmania .
Appearance and characteristics
The Australian angel shark can reach a maximum body length of about 150 cm. As with other angel sharks, the body is strongly flattened with very broad pectoral fins , which makes the animals look more like long rays in shape . However, the pectoral fins are clearly separated from the trunk, while in most rays they merge seamlessly into the body. They have two dorsal fins and no anal fin . The body has a dark gray-brown back color with numerous light and a few dark spots. The fins have a light border, and there are spots on the leading edge of the light dorsal fins and on the lower caudal lobe. There are no thorns on the snout area of the adult sharks, while the juveniles have enlarged denticles in the area of the snout, around the eyes and on the back.
The eyes are on the top of the head, the mouth is terminal, the outer nostrils are provided with short barbels . The injection holes are small, the number of side gill openings is five. The nasal flaps and barbels are badly frayed.
distribution
The distribution area of the Australian angel shark is in the coastal area of southern Australia from New South Wales to southern Western Australia and around Tasmania . It can be found from the shallow beach area to the outer edge of the continental shelf at depths of up to 120 meters. It prefers sandy and muddy surfaces, and it is also often found in seagrass meadows and near stony reefs .
Way of life
Like other angel sharks, it feeds mainly on small bony fish and crustaceans , which it prey on lying on the ground as a lurker . During the day it lies buried on the seabed, at night it is active. Like all angel sharks, it is ovoviviparous - the eggs are hatched in the mother before the young are born alive. The females of this species give birth to up to 20 young animals, with the time of birth being in autumn.
The animals reach sexual maturity with a body length of about 90 centimeters.
Danger
The International Union for Conservation of Nature (IUCN) classifies this shark as not endangered ("Least Concern"). The species is fished and is also threatened by bottom and trawling fishing, which is not used in large parts of its range. Since there was no decline in populations between 1992 and 2001, the species was classified as not endangered. According to the IUCN, further observation is necessary, especially in the catchment area of the South East Trawl Fishery.
supporting documents
- ↑ a b Squatina australis in the endangered Red List species the IUCN 2010. Posted by: Pogonoski, J. & Pollard, D. (SSG Australia & Oceania Regional Workshop, March 2003), 2003. Retrieved on December 18 of 2010.
literature
- Leonard Compagno , Marc Dando, Sarah Fowler: Sharks of the World . Princeton University Press , Princeton and Oxford 2005, pp. 140 ISBN 978-0-691-12072-0
