Squalus
''Squalus'' is a genus of dogfish sharks in the family (biology), family Squalidae. Commonly known as spurdogs, these sharks are characterized by smooth dorsal fin spines, teeth in upper and lower fish jaw, jaws similar in size, caudal peduncle with lateral keels; upper precaudal pit usually present, and caudal fin without subterminal notch. In spurdogs, the hyomandibula (the bone connecting the braincase to the jaws) is oriented at a right angle to the neurocranium, while in other sharks, the hyomandibula runs more parallel to the body. This led some to think that the upper jaw of ''Squalus'' would not be as protractile as the jaws of other sharks. However, a study that compared different jaw suspension types in sharks showed that this is not the case and that ''Squalus'' is quite capable of protruding its upper jaw during feeding.Wilga, C.D., Motta, P.J. & Sanford, C.P. (2007): Evolution and ecology of feeding in elasmobranchs. ''Integrative and Comparative Biology, 47 (1): 55-6 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Spiny Dogfish
The spiny dogfish (''Squalus acanthias''), spurdog, mud shark, or piked dogfish is one of the best known species of the Squalidae (dogfish) family of sharks, which is part of the Squaliformes order. While these common names may apply to several species, ''Squalus acanthias'' is distinguished by two spines (one anterior to each dorsal fin) and no anal fin. It lives in shallow waters and further offshore in most parts of the world, especially in temperate waters. Those in the northern Pacific Ocean were reevaluated in 2010 and found to constitute a separate species, now called the Pacific spiny dogfish (''Squalus suckleyi''). Description and behaviour The spiny dogfish has dorsal fins, no anal fin, and white spots along its back. The caudal fin has asymmetrical lobes, forming a heterocercal tail. The species name ''acanthias'' refers to the shark's two spines. These are used defensively. If captured, the shark can arch its back to pierce its captor with spines near the dorsal ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Acanthias
The spiny dogfish (''Squalus acanthias''), spurdog, mud shark, or piked dogfish is one of the best known species of the Squalidae (dogfish) family of sharks, which is part of the Squaliformes order. While these common names may apply to several species, ''Squalus acanthias'' is distinguished by two spines (one anterior to each dorsal fin) and no anal fin. It lives in shallow waters and further offshore in most parts of the world, especially in temperate waters. Those in the northern Pacific Ocean were reevaluated in 2010 and found to constitute a separate species, now called the Pacific spiny dogfish (''Squalus suckleyi''). Description and behaviour The spiny dogfish has dorsal fins, no anal fin, and white spots along its back. The caudal fin has asymmetrical lobes, forming a heterocercal tail. The species name ''acanthias'' refers to the shark's two spines. These are used defensively. If captured, the shark can arch its back to pierce its captor with spines near the d ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalidae
Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish, are one of several families of sharks categorized under Squaliformes, making it the second largest order of sharks, numbering 119 species across 7 families. Having earned their name after a group of fishermen reportedly observed the species chasing down smaller fish in dog-like packs, dogfish have slender, streamlined bodies, usually more compact in comparison to other species, and a pointed snout. Dogfish likewise have two dorsal fins, each with smooth spines, but no anal fin, and their skin is generally rough to the touch. As the species reaches adulthood, males usually measure a maximum of , while females typically measure long. The species therefore exhibits female-dominant sexual dimorphism. Dogfish sharks have slate-grey or grey-brown skin with white dots that becomes paler (almost white) around the belly region. These sharks are characterized by teeth in upper and lower jaws similar in size; a cauda ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Blainville
The longnose spurdog (''Squalus blainville'') is a dogfish shark of the genus ''Squalus'', found over continental shelves A continental shelf is a portion of a continent that is submerged under an area of relatively shallow water, known as a shelf sea. Much of these shelves were exposed by drops in sea level during glacial periods. The shelf surrounding an island ... in all oceans, at depths of between 15 and 800 metres. They reach one metre in length. References * * Tony Ayling & Geoffrey Cox, ''Collins Guide to the Sea Fishes of New Zealand'', (William Collins Publishers Ltd, Auckland, New Zealand 1982) {{DEFAULTSORT:Longnose spurdog Squalus Fish described in 1827 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Brevirostris
The Japanese shortnose spurdog (''Squalus brevirostris'') is a dogfish shark in the genus ''Squalus''. It is found from southern Japan to the South China Sea The South China Sea is a marginal sea of the Western Pacific Ocean. It is bounded in the north by South China, in the west by the Indochinese Peninsula, in the east by the islands of Taiwan island, Taiwan and northwestern Philippines (mainly Luz .... The length of the longest specimen measured is . References {{DEFAULTSORT:Japanese shortnose spurdog Squalus Fish described in 1917 Taxa named by Shigeho Tanaka ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Albifrons
''Squalus albifrons'', the eastern highfin spurdog, is a dogfish described in 2007. It is a member of the family Squalidae, found on the continental shelf off Queensland, Australia, at depths between 220 and 510 m. The length of the longest specimen measured is . Its reproduction is ovoviviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a "bridging" form of reproduction between egg-laying oviparity, oviparous and live-bearing viviparity, viviparous reproduction. Ovoviviparous animals possess embryos that develo .... References {{Taxonbar, from=Q2891490 albifrons Marine fish of Eastern Australia Fish described in 2007 Taxa named by Peter R. Last Taxa named by William Toby White Taxa named by John D. Stevens ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Altipinnis
''Squalus altipinnis'', the western highfin spurdog, is a dogfish of the family Squalidae found on the continental shelf off Western Australia, at depths between 220 and 510 m. Its reproduction is ovoviviparous Ovoviviparity, ovovivipary, ovivipary, or aplacental viviparity is a "bridging" form of reproduction between egg-laying oviparity, oviparous and live-bearing viviparity, viviparous reproduction. Ovoviviparous animals possess embryos that develo .... Compagno, Dando, & Fowler, ''Sharks of the World'', Princeton University Press, New Jersey 2005 References altipinnis Fish of Australia Fish described in 2007 Taxa named by Peter R. Last Taxa named by William Toby White Taxa named by John D. Stevens {{Shark-stub ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squaliformes
The Squaliformes are an order of sharks that includes about 126 species in seven families. Members of the order have two dorsal fins, which usually possess spines, they usually have a sharp head, no anal fin or nictitating membrane, and five to seven gill slits. In most other respects, however, they are quite variable in form and size. Most species of the squaliform order live in saltwater or brackish water. They are found worldwide, from northern to tropical waters, and from shallow coastal seas to the open ocean. All members of the family Etmoperidae and Dalatiidae and ''Zameus squamulosus'' possess photophores, luminous organs, and exhibit intrinsic bioluminescence. Bioluminescence evolved once in Squaliformes, approximately 111–153 million years ago, and helped the Squaliformes radiate and adapt to the deep sea. The common ancestor of Dalatiidae, Etmopteridae, Somniosidae, and Oxynotidae possessed a luminous organ and used bioluminescence for camouflage by co ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Albicaudus
The Brazilian whitetail dogfish (''Squalus albicaudus'') is a dogfish described in 2016. It is a member of the family Squalidae, found off the coast of Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population ..., at depths between 195 – 421 meters. The length of the longest specimen measured is . References {{DEFAULTSORT:Brazilian whitetail dogfish Squalus Marine fish of Brazil Fish described in 2016 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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Squalus Bahiensis
The northeastern Brazilian dogfish (''Squalus bahiensis'') is a species of dogfish that was scientifically described in 2016. It is a member of the family Squalidae and is found off the coast of Brazil Brazil, officially the Federative Republic of Brazil, is the largest country in South America. It is the world's List of countries and dependencies by area, fifth-largest country by area and the List of countries and dependencies by population .... The longest recorded specimen reaches 69.0 cm (27.2 in) in length. References {{DEFAULTSORT:Northeastern Brazilian dogfish Squalus Marine fish of Brazil Fish described in 2016 ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |
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William Toby White
William Toby White is an Australian ichthyologist. He studies speciation and biodiversity of shark, ray, and skate species (subclass Elasmobranchii) through morphological and molecular systematics. Education White received bachelor's (1997) and doctoral (2003) degrees in Biological Science from Murdoch University in Perth, Australia. His doctoral thesis, "Aspects of the biology of elasmobranchs in a subtropical embayment in Western Australia and of chondrichthyan fisheries in Indonesia", examined 1) spatial partitioning of food resources available to shark, ray, and skate species in Shark Bay (off the western coast of Australia), and 2) the relative frequencies of shark, ray, and skate species caught in fisheries off the coast of southeastern Indonesia. From 2004 to 2006 he did post-doctoral training, also at Murdoch University. Professional career Since 2006, White has served as ichthyologist at the Australian National Fish Collection which is part of the CSIRO Marine ... [...More Info...]       [...Related Items...]     OR:     [Wikipedia]   [Google]   [Baidu]   |