Angelshark

Angel sharks
Sand devil, Squatina dumeril
Conservation status
Critically endangered
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Chondrichthyes
Subclass:	Elasmobranchii
Order:	Squatiniformes Buen, 1926
Family:	Squatinidae Bonaparte, 1838
Genus:	Squatina Duméril, 1806
Species
See text.

Template:Sharksportal The angel sharks are an unusual group of sharks with flattened bodies and broad pectoral fins that give them a strong resemblance to skates and rays. The 16-odd known species are all classified in a single genus, Squatina, belonging to its own family, Squatinidae, and order Squatiniformes. They occur worldwide in temperate and tropical seas.

Appearance

While the forward part of the angel shark's body is broad and flattened, the rear part retains a muscular appearance more typical of other sharks. The eyes and spiracles are on top, and the five gill slits are on bottom. Both the pectorals and the pelvic fins are large and held horizontally. There are two dorsal fins, no anal fin, and unusually for sharks, the lower lobe of the caudal fin is longer than the upper lobe. Most types grow to a length of 1.5 m (5 ft), with the Japanese angelshark, Squatina japonica, known to reach 2 meters.

Habitat

Angel sharks are bottom-dwellers, burying themselves in sand or mud, then lunging to snap up prey, which includes fish, crustaceans, and various types of mollusks. The Pacific angelshark, Squatina californica, is also known to leave the bottom at night to forage.

Behavior

Although they are not normally aggressive, they do bite when stepped on or handled.

Reproduction

Angel sharks are ovoviviparous, with litters known up to 13 pups.

Commercial value

The sharks were long considered of no commercial interest, but in 1978, Michael Wagner, a fish processor in Santa Barbara, California began to promote angel sharks, and 310 metric tons were taken off California in 1984. The fishery devastated the population and is now regulated.

Protection

Angel sharks have been declared a critically endangered species by the World Conservation Union (IUCN). Their numbers have deteriorated so much that in some bodies of water, including the North Sea, they have become extinct.

Species

• Sawback angelshark, Squatina aculeata Cuvier, 1829 188 cm [1]
• African angelshark, Squatina africana Regan, 1908 80 cm [2]
• Argentine angelshark, Squatina argentina (Marini, 1930) 170 cm [3]
• Chilean angelshark, Squatina armata (Philippi, 1887)
• Australian angelshark, Squatina australis Regan, 1906 152 cm [4]
• Pacific angelshark, Squatina californica Ayres, 1859 152 cm [5]
• Sand devil, Squatina dumeril Lesueur, 1818 152 cm [6]
• Taiwan angelshark, Squatina formosa Shen & Ting, 1972 [7]
• Angular angel shark, Squatina guggenheim Marini, 1936 [8]
• Japanese angelshark, Squatina japonica Bleeker, 1858 200 cm [9]
• Clouded angelshark, Squatina nebulosa Regan, 1906 [10]
• Hidden angel shark, Squatina occulta Vooren & da Silva, 1992 [11]
• Smoothback angelshark, Squatina oculata Bonaparte, 1840
• Squatina punctata Marini, 1936 [12]
• Squatina squatina (Linnaeus, 1758), 183 cm [13]
• Ornate angelshark, Squatina tergocellata McCulloch, 1914 100 cm [14]
• Ocellated angelshark, Squatina tergocellatoides Chen, 1963 63 cm [15]
• Eastern Australian angelshark, Squatina sp. A (provisional scientic name)
• Western Australian angelshark, Squatina sp. B (provisional scientic name)
• Cortez angelshark, Squatina sp. (provisional scientic name)

References

• "Squatina". Integrated Taxonomic Information System. 4 May. {{cite web}}: Check date values in: |date= and |year= / |date= mismatch (help)

See also

• List of sharks

External links

• OceanFootage Angel Shark Images and Video Clips
• Reefquest page on angel sharks
• Monterey Bay Aquarium page on Pacific angel shark
• http://www.elasmo-research.org/education/topics/d_checklist.htm (also a reference)