"Squalid" redirects here. Not to be confused with Squalor.
Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish,[2] are one of several families of sharks categorized under Squaliformes, making it the second largest order of sharks, numbering 119 species across 7 families.[3] Having earned their name after a group of fishermen reportedly observed the species chasing down smaller fish in dog-like packs,[4] 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.[1] As the species reaches adulthood, males usually measure a maximum of 100 cm (39 inches), while females typically measure 125 cm (49 inches) 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 caudal peduncle with lateral keels; the upper precaudal pit usually is present; and the caudal fin is without a subterminal notch.
They are carnivorous, principally preying upon organisms smaller than themselves. Some of their prey include herring, mackerel, and capelin. In special cases, they may consume jellyfish and squid. Even at a young age, spiny dogfish pups may hunt fish two or three times their size.[citation needed] Unlike virtually all other shark species, dogfish sharks possess venom which coats their dorsal spines; this venom is mildly toxic to humans and would be harmful if the shark were to be mishandled. The livers and stomachs of the Squalidae contain the compound squalamine, which possesses the property of reduction of small blood vessel growth in humans.[5] Dogfish sharks use their strong jaw and sharp teeth to consume their prey.
The spiny dogfish has broken several records in the areas of migration and gestation. This shark tends to be a highly migratory species: one shark was recorded as travelling 8,000 km (5,000 miles) after being tagged in Washington state, United States, and found again later in Japan. In addition to its long distance migration, the spiny shark holds the record for longest gestation period of any other vertebrate at 22–24 months. Females produce eggs and give birth to live young that measure to be 20–33 cm (8–13 inches).
TaxonomyEdit
Dogfish are scientifically classified as the Squalidae family, categorized under the Squaliform order, which encompasses seven families in total, including Squalidae. The Squalidae family itself contains two separate genera: Cirrhigaleus and Squalus, numbering 37 species between the two.
Genus: Within the Squalidae dogshark family, are two known genera
Squalus: The Squalus genus encompasses 34 different species of dogfish, or spurdogs, home to waters all around the world. With the exception of one – Squalus margaretsmithae, or Smith's dogfish shark, known to be a maximum of 55 cm (21.3 inches) in length [6] – species classified under the genus are known to range from 56 to 160 cm (22 to 63 inches) in length.[7] While the majority of the species are characterized by their slate or blue-grey body coloration and white underbelly, only 2 – Squalus acanthias and Squalus suckleyi – are more easily recognizable by the notable, evenly-spaced array of small white dots decorating their darker dorsal sides.[8]
Cirrhigaleus: In contrast to its counterpart genus, Cirrhigaleus currently includes only 3 species, the most recent of which, Cirrhigaleus australis, was discovered and classified in 2007.[9] Cirrhigaleus species are typically the larger of the two Squalidae genera, ranging from 120 to 125 cm (47 to 49.5 inches) in length (although the largest species of 160 cm (63 inches), Squalus acanthias, is classified under the Squalus genus, the vast majority of the species within the same genus remain under or around 100 cm (39 inches) in length, whereas only 3 of 34 total species exceed 120 cm (47 inches).[10] The genus likewise shares many phenotypic similarities with its Squalus counterpart, namely the blue-grey body coloration, white underbelly, and basic morphology, however with some variation; common body coloration may also be a grey-brown hue, and most notably, Cirrhigaleus differs from Squalus in having extremely long nasal barbels, and small black instead of white spots in a similar pattern.[11]
for a full list of species in each genera: list of sharks
Squalus acanthias, or the spiny dogfish (adult), with grey-brown body coloration, decorated by evenly-spaced, small, white dots, and lighter underbelly.Cirrhigaleus barbifer, or the Mandarin dogfish (adult), pictured with grey-brown body coloration, decorated in an array of speckled black dots, with a lighter underbelly, and elongated nasal barbels.
^Straube, N.; Li, C.; Claes, J.M. (2015). "Molecular phylogeny of Squaliformes and first occurrence of bioluminescence in sharks". BMC Evolutionary Biology. 15 (162). doi:10.1186/s12862-015-0446-6. PMC4537554.
^"From the Belly of a Shark, a Cancer Cure?". National Geographic. Vol. 193, no. 6. June 1998. p. 202. Retrieved 2 January 2023.
^de F. L. Viana, S. T.; Lisher, M. W.; de Carvalho, M. R. (2018). "Two new species of short-snouted dogfish sharks of the genus Squalus Linnaeus, 1758, from southern Africa (Chondrichthyes: Squaliformes: Squalidae)". Marine Biodiversity. 48: 1787–1814. doi:10.1007/s12526-017-0673-8.
^Froese, R.; Pauly, D. "Genus: Squalus". fishbase.org. FishBase.
^Ebert, D. A. (2010). "Resurrection and redescription of Squalus suckleyi (Girard, 1854) from the North Pacific, with comments on the Squalus acanthias subgroup (Squaliformes: Squalidae)". Zootaxa. 2612 (1): 22–40.
^White, W. T.; Last, P. R.; Stevens., J. D. (2007). "Cirrhigaleus australis n. sp., a new Mandarin dogfish (Squaliformes: Squalidae) from the south-west Pacific". Zootaxa. 1560 (1): 19–30. doi:10.11646/ZOOTAXA.1560.1.2.
^Froese, R.; Pauly, D. "Genus: Cirrhigaleus". fishbase.org. FishBase.
^Tanaka, Shigeho (1917). "Three new species from Japan". Zoology. 29: 225–226.
Further readingEdit
Froese, Rainer, and Daniel Pauly, eds. (2011). "Squalidae" in FishBase. February 2011 version.
squalidae, squalid, redirects, here, confused, with, squalor, more, commonly, known, dogfish, sharks, spiny, dogfish, several, families, sharks, categorized, under, squaliformes, making, second, largest, order, sharks, numbering, species, across, families, hav. Squalid redirects here Not to be confused with Squalor Squalidae more commonly known as dogfish dog sharks or spiny dogfish 2 are one of several families of sharks categorized under Squaliformes making it the second largest order of sharks numbering 119 species across 7 families 3 Having earned their name after a group of fishermen reportedly observed the species chasing down smaller fish in dog like packs 4 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 1 As the species reaches adulthood males usually measure a maximum of 100 cm 39 inches while females typically measure 125 cm 49 inches long The species therefore exhibits female dominant sexual dimorphism Dogfish sharksTemporal range Upper Cretaceous Recent PreꞒ Ꞓ O S D C P T J K Pg N 1 Spiny dogfish Squalus acanthiasScientific classificationDomain EukaryotaKingdom AnimaliaPhylum ChordataClass ChondrichthyesOrder SqualiformesFamily SqualidaeBonaparte 1834GeneraCirrhigaleus SqualusDogfish 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 caudal peduncle with lateral keels the upper precaudal pit usually is present and the caudal fin is without a subterminal notch They are carnivorous principally preying upon organisms smaller than themselves Some of their prey include herring mackerel and capelin In special cases they may consume jellyfish and squid Even at a young age spiny dogfish pups may hunt fish two or three times their size citation needed Unlike virtually all other shark species dogfish sharks possess venom which coats their dorsal spines this venom is mildly toxic to humans and would be harmful if the shark were to be mishandled The livers and stomachs of the Squalidae contain the compound squalamine which possesses the property of reduction of small blood vessel growth in humans 5 Dogfish sharks use their strong jaw and sharp teeth to consume their prey The spiny dogfish has broken several records in the areas of migration and gestation This shark tends to be a highly migratory species one shark was recorded as travelling 8 000 km 5 000 miles after being tagged in Washington state United States and found again later in Japan In addition to its long distance migration the spiny shark holds the record for longest gestation period of any other vertebrate at 22 24 months Females produce eggs and give birth to live young that measure to be 20 33 cm 8 13 inches Taxonomy EditDogfish are scientifically classified as the Squalidae family categorized under the Squaliform order which encompasses seven families in total including Squalidae The Squalidae family itself contains two separate genera Cirrhigaleus and Squalus numbering 37 species between the two Squalidae ClassificationOrder Squaliformes Family Within Squaliforme order there are seven families Centrophoridae gulper sharks Dalatiidae kite fin sharks Echinorhinidae bramble sharks Etmopteridae lantern sharks Oxynotidae rough sharks Somniosidae sleeper sharks Squalidae dogfish sharksGenus Within the Squalidae dogshark family are two known genera Squalus The Squalus genus encompasses 34 different species of dogfish or spurdogs home to waters all around the world With the exception of one Squalus margaretsmithae or Smith s dogfish shark known to be a maximum of 55 cm 21 3 inches in length 6 species classified under the genus are known to range from 56 to 160 cm 22 to 63 inches in length 7 While the majority of the species are characterized by their slate or blue grey body coloration and white underbelly only 2 Squalus acanthias and Squalus suckleyi are more easily recognizable by the notable evenly spaced array of small white dots decorating their darker dorsal sides 8 Cirrhigaleus In contrast to its counterpart genus Cirrhigaleus currently includes only 3 species the most recent of which Cirrhigaleus australis was discovered and classified in 2007 9 Cirrhigaleus species are typically the larger of the two Squalidae genera ranging from 120 to 125 cm 47 to 49 5 inches in length although the largest species of 160 cm 63 inches Squalus acanthias is classified under the Squalus genus the vast majority of the species within the same genus remain under or around 100 cm 39 inches in length whereas only 3 of 34 total species exceed 120 cm 47 inches 10 The genus likewise shares many phenotypic similarities with its Squalus counterpart namely the blue grey body coloration white underbelly and basic morphology however with some variation common body coloration may also be a grey brown hue and most notably Cirrhigaleus differs from Squalus in having extremely long nasal barbels and small black instead of white spots in a similar pattern 11 for a full list of species in each genera list of sharks nbsp Squalus acanthias or the spiny dogfish adult with grey brown body coloration decorated by evenly spaced small white dots and lighter underbelly nbsp Cirrhigaleus barbifer or the Mandarin dogfish adult pictured with grey brown body coloration decorated in an array of speckled black dots with a lighter underbelly and elongated nasal barbels References Edit nbsp Sharks portal a b Froese Rainer and Daniel Pauly eds 2009 Squalidae in FishBase January 2009 version Squalidae Integrated Taxonomic Information System Retrieved 16 November 2013 Straube N Li C Claes J M 2015 Molecular phylogeny of Squaliformes and first occurrence of bioluminescence in sharks BMC Evolutionary Biology 15 162 doi 10 1186 s12862 015 0446 6 PMC 4537554 Spiny Dogfish Oceana Retrieved 2019 04 12 From the Belly of a Shark a Cancer Cure National Geographic Vol 193 no 6 June 1998 p 202 Retrieved 2 January 2023 de F L Viana S T Lisher M W de Carvalho M R 2018 Two new species of short snouted dogfish sharks of the genus Squalus Linnaeus 1758 from southern Africa Chondrichthyes Squaliformes Squalidae Marine Biodiversity 48 1787 1814 doi 10 1007 s12526 017 0673 8 Froese R Pauly D Genus Squalus fishbase org FishBase Ebert D A 2010 Resurrection and redescription of Squalus suckleyi Girard 1854 from the North Pacific with comments on the Squalus acanthias subgroup Squaliformes Squalidae Zootaxa 2612 1 22 40 White W T Last P R Stevens J D 2007 Cirrhigaleus australis n sp a new Mandarin dogfish Squaliformes Squalidae from the south west Pacific Zootaxa 1560 1 19 30 doi 10 11646 ZOOTAXA 1560 1 2 Froese R Pauly D Genus Cirrhigaleus fishbase org FishBase Tanaka Shigeho 1917 Three new species from Japan Zoology 29 225 226 Further reading EditFroese Rainer and Daniel Pauly eds 2011 Squalidae in FishBase February 2011 version Compagno Leonard J V Dando Mark Fowler Sarah L 2005 Sharks of the World New Jersey Princeton University Press ISBN 0 691 12072 2 Retrieved from https en wikipedia org w index php title Squalidae amp oldid 1180317142, wikipedia, wiki, book, books, library,
