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Squaliform
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 Eptomeridae 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 count ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinorhinus
''Echinorhinus'' is the only extant genus in the family Echinorhinidae. Taxonomy Echinorhinidae are traditionally classified in the order Squaliformes, together with kitefin and gulper sharks.Compagno, 2005. "Sharks of the World". However, a phylogenetic estimate based on gene capture data and mitochondrial data suggests that they are not squaliform sharks, but may be more likely to be appropriately classed in their own group, as a sister group to angel sharks and sawsharks. Phylogenetic placement of Echinorhinidae has been ambiguous in morphological and molecular studies, either being included within Squaliformes, considered sister to Squaliformes, or placed in a separate group with Sawsharks (Pristiophoriformes) or angel sharks (Squatiniformes). For this reason they are sometimes given their own order, Echinorhiniformes. Etymology The name is from Greek ''echinos'' meaning "spiny" and ''rhinos'' meaning "nose". Species * ''Echinorhinus brucus'' Bonnaterre, 1788 (brambl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Echinorhinidae
''Echinorhinus'' is the only extant genus in the family Echinorhinidae. Taxonomy Echinorhinidae are traditionally classified in the order Squaliformes, together with kitefin and gulper sharks.Compagno, 2005. "Sharks of the World". However, a phylogenetic estimate based on gene capture data and mitochondrial data suggests that they are not squaliform sharks, but may be more likely to be appropriately classed in their own group, as a sister group to angel sharks and sawsharks. Phylogenetic placement of Echinorhinidae has been ambiguous in morphological and molecular studies, either being included within Squaliformes, considered sister to Squaliformes, or placed in a separate group with Sawsharks (Pristiophoriformes) or angel sharks (Squatiniformes). For this reason they are sometimes given their own order, Echinorhiniformes. Etymology The name is from Greek ''echinos'' meaning "spiny" and ''rhinos'' meaning "nose". Species * ''Echinorhinus brucus'' Bonnaterre, 1788 (brambl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 dorsal f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euprotomicroides
The taillight shark (''Euprotomicroides zantedeschia'') is a little-known species of shark in the family Dalatiidae and the only member of its genus.Stehmann, M.F.W., Van Oijen, M. & Kamminga, P. (2016): Re-description of the rare taillight shark ''Euprotomicroides zantedeschia'' (Squaliformes, Dalatiidae), based on third and fourth record from off Chile. ''Cybium, 40 (3): 187-197.'' It is known from only four specimens collected from deep oceanic waters in the southern Atlantic Ocean and Pacific Ocean. A small shark with a laterally compressed body and a bulbous snout, this species has unusual adaptations that indicate a specialized lifestyle: its pectoral fins are paddle-like and may be used for propulsion, unlike other sharks and it has a pouch-like gland on its abdomen that emits clouds of luminescent blue fluid. This shark is likely aplacental viviparous and a formidable predator for its size. Taxonomy and phylogeny The first specimen of the taillight shark was collected b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pacific Spiny Dogfish
The Pacific spiny dogfish (''Squalus suckleyi'') is a common species of the Squalidae (dogfish) family of sharks and are among the most abundant species of sharks in the world. This species is closely related to ''Squalus acanthias'' and for many years they were treated as a single species. Recent research, using meristic, morphological and molecular data led to the resurrection of Pacific Spiny Dogfish as a separate species. The American Fisheries Society recommends the common name "Pacific Spiny Dogfish" for ''Squalus suckleyi'' over alternatives such as "Spotted Spiny Dogfish" and "North Pacific Spiny Dogfish" and "Spiny Dogfish" for ''Squalus acanthias''. The maximum length of a Pacific dogfish can be , and they can live up to 100 years. ''Squalus suckleyi'' has a slower growth rate, larger maximum size, and later maturity compared to ''Squalus acanthias'' species. The slower growth rate and time of maturity could be related to the colder temperatures these sharks face. Pacifi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dalatiidae
The Dalatiidae are the family of kitefin sharks of the order Squaliformes (the term "kitefin shark" also refers specifically to the species ''Dalatias licha''). Members of this family are small, under long, and are found worldwide. They have cigar-shaped bodies with narrow heads and rounded snouts. Several species have specialized bioluminescent organs. Though eight genera are in this family, four of them are monotypic. Genera and species * ''Dalatias'' Rafinesque, 1810 ** ''Dalatias licha'' ( Bonnaterre, 1788) (kitefin shark) ** †''Dalatias orientalis'' (Malyshkina ''et al.'', 2022) * ''Euprotomicroides'' Hulley and M. J. Penrith, 1966 ** ''Euprotomicroides zantedeschia'' Hulley and M. J. Penrith, 1966 (tail-light shark) * ''Euprotomicrus'' T. N. Gill, 1865 ** '' Euprotomicrus bispinatus'' ( Quoy & Gaimard, 1824) (pygmy shark) * '' Heteroscymnoides'' Fowler, 1934 ** ''Heteroscymnoides marleyi'' Fowler, 1934 (longnose pygmy shark) * ''Isistius'' T. N. Gill, 1865 **'' Isist ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etmopteridae
The Etmopteridae are a family of sharks in the order Squaliformes, commonly known as lantern sharks. Their name comes from the presence of light-producing photophore A photophore is a glandular organ that appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors, ...s on their bodies. The members of this family are small, under long, and are found in deep waters worldwide. The 45 species are placed in five genera. Three-quarters of the species are in the genus ''Etmopterus''. Genera * '' Aculeola'' * '' Centroscyllium'' * '' Etmopterus'' * †'' Paraetmopterus'' * '' Trigonognathus'' References {{Taxonbar, from=Q720466 Shark families Taxa named by Henry Weed Fowler ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squaliolus
''Squaliolus'' is a genus of deep-sea squaliform sharks in the family Dalatiidae. Species * ''Squaliolus aliae'' Teng, 1959 ( smalleye pygmy shark) * ''Squaliolus laticaudus'' H. M. Smith & Radcliffe, 1912 ( spined pygmy shark) See also * List of prehistoric cartilaginous fish This list of prehistoric cartilaginous fish genera is an attempt to create a comprehensive listing of all genera that have ever been included in the class chondrichthyes ''and'' are known from the fossil record. This list excludes purely vernacula ... References {{Taxonbar, from=Q2355052 Shark genera Taxa named by Hugh McCormick Smith Taxa named by Lewis Radcliffe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Euprotomicrus
The pygmy shark (''Euprotomicrus bispinatus''), the second-smallest of all the shark species after the dwarf lanternshark, is a squaliform shark of the family Dalatiidae, the only member of the genus ''Euprotomicrus''. Their lengths are up to about 25 cm (10 in) for females and about 22 cm (8.7 in) for males. Pygmy sharks are ovoviviparous and produce about eight young in each litter. Conservation status In June 2018 the New Zealand Department of Conservation classified the pygmy shark as "Not Threatened" with the qualifier "Secure Overseas" under the New Zealand Threat Classification System The New Zealand Threat Classification System is used by the Department of Conservation to assess conservation priorities of species in New Zealand. The system was developed because the IUCN Red List, a similar conservation status system, had some .... References {{DEFAULTSORT:Pygmy shark Dalatiidae Taxa named by Jean René Constant Quoy Taxa named by Joseph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isistius
''Isistius'' is a genus of Squaliformes, dogfish sharks in the family (biology), family Dalatiidae. They are commonly known as cookiecutter sharks. Members of the genus are known for their unusual behaviour and dentition. Species *''Isistius brasiliensis'' Jean René Constant Quoy, Quoy & Joseph Paul Gaimard, Gaimard, 1824 (cookiecutter shark) *''Isistius plutodus'' Jack Garrick, Garrick & Stewart Springer, S. Springer, 1964 (largetooth cookiecutter shark) *†''Isistius triangulus Probst, 1879 *†''Isistius trituratus Winkler, 1876 Habits The cookiecutter sharks, or cigar sharks, are unusual in the manner in which they replace their teeth. Instead of replacing teeth singly as they get damaged or lost, for example in hunting, such sharks replace the whole set. They can repeat such replacement throughout their lifetimes. Cookiecutter sharks often attack large shoals of fish, but have been known to circle fishing vessels to get an easy meal. They are particularly notorious for b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mollisquama
''Mollisquama'' is a genus of pocket sharks in the family Dalatiidae. There are two known species each only known from a single specimen; one found off the coast of Chile and the other found in the Gulf of Mexico. Species There are currently two known species:Katz, Brigit. "This New Shark Species Looks Like a Tiny Sperm Whale". ''Smithsonian''. Retrieved 01 January 2021. * ''Mollisquama mississippiensis'' * ''Mollisquama parini The pocket shark (''Mollisquama parini'') is a species of kitefin shark in the family Dalatiidae. The species is found in deep water off Chile in the southeastern Pacific Ocean. It was the only member of the genus ''Mollisquama'', until another ...'' References Dalatiidae Shark genera {{Shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
