''Squalus'' is a
genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial no ...
of
dogfish shark
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 t ...
s in the
family
Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Ideal ...
Squalidae. Commonly known as spurdogs, these
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 Selachimo ...
s are characterized by smooth
dorsal fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through co ...
spines, teeth in upper and lower
jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term ''jaws'' is also broadly applied to the whole of the structures constituting the vault of the mouth and serv ...
s similar in size,
caudal peduncle
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...
with lateral keels; upper precaudal pit usually present, and
caudal fin
Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...
without subterminal notch. In spurdogs, the hyomandibula (the bone connecting the braincase to the jaws) is oriented at a right angle to the
neurocranium
In human anatomy, the neurocranium, also known as the braincase, brainpan, or brain-pan is the upper and back part of the skull, which forms a protective case around the brain. In the human skull, the neurocranium includes the calvaria or sku ...
, 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): 55-69.'']
The name comes from ''squalus'', the
Latin
Latin (, or , ) is a classical language belonging to the Italic languages, Italic branch of the Indo-European languages. Latin was originally a dialect spoken in the lower Tiber area (then known as Latium) around present-day Rome, but through ...
for shark; this word is the root for numerous words related to sharks such as squaline and
scientific name
In taxonomy, binomial nomenclature ("two-term naming system"), also called nomenclature ("two-name naming system") or binary nomenclature, is a formal system of naming species of living things by giving each a name composed of two parts, bo ...
s for sharks, such as the order
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 fi ...
.
Species
Currently, 32 recognized species are placed in this genus:
* ''
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 sever ...
''
Linnaeus
Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, ...
, 1758
Events
January–March
* January 1 – Swedish biologist Carl Linnaeus (Carl von Linné) publishes in Stockholm the first volume (''Animalia'') of the 10th edition of ''Systema Naturae'', the starting point of modern zoologic ...
(spiny dogfish)
[
* '']Squalus albicaudus
The Brazilian whitetail dogfish (''Squalus albicaudus'') is a dogfish described in 2016. It is a member of the family Squalidae
Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish, are one of several families of sharks ...
'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (Brazilian whitetail dogfish) [Viana, S.T.d.F., Carvalho, M.R.d. & Gomes, U.L. (2016): Taxonomy and morphology of species of the genus ''Squalus'' Linnaeus, 1758 from the Southwestern Atlantic Ocean (Chondrichthyes: Squaliformes: Squalidae). ''Zootaxa, 4133 (1): 1-89.'']
* ''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 s ...
'' Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, W. T. White & J. D. Stevens, 2007 (eastern highfin spurdog)
* ''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, o ...
'' Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, W. T. White & J. D. Stevens, 2007 (western highfin spurdog)
* ''Squalus bahiensis
The northeastern Brazilian dogfish (''Squalus bahiensis'') is a dogfish described in 2016. It is a member of the family Squalidae
Squalidae, more commonly known as dogfish, dog sharks, or spiny dogfish, are one of several families of shark ...
'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (northeastern Brazilian dogfish) [
* '']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 ...
'' ( A. Risso, 1827) (longnose spurdog)
* ''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 ...
'' S. Tanaka (I), 1917 (Japanese shortnose spurdog)
* '' Squalus bucephalus'' Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, Séret & Pogonoski, 2007 (bighead spurdog)
* '' Squalus chloroculus'' Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, W. T. White & Motomura, 2007 (greeneye spurdog)
* '' Squalus clarkae'' Pfleger, Grubbs, Cotton & Daly-Engel, 2018 (Genie's dogfish)
* '' Squalus crassispinus'' Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, M. J. Edmunds & Yearsley, 2007 (fatspine spurdog)
* '' Squalus cubensis'' Howell-Rivero, 1936 (Cuban dogfish)
* '' Squalus edmundsi'' W. T. White, Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
& J. D. Stevens, 2007 (Edmund's spurdog)
* '' Squalus formosus'' W. T. White & Iglésias, 2011 (Taiwan spurdog)
* '' Squalus grahami'' W. T. White, Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
& J. D. Stevens, 2007 (eastern longnose spurdog)
* '' Squalus griffini'' Phillipps, 1931 (northern spiny dogfish)
* '' Squalus hawaiiensis'' Daly-Engel, Koch, Anderson, Cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus ''Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor pe ...
, Grubbs, 2018 (Hawaiian spurdog)
* '' Squalus hemipinnis'' W. T. White, Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
& Yearsley, 2007 (Indonesian shortsnout spurdog)
* '' Squalus japonicus'' Ishikawa, 1908 (Japanese spurdog)
* '' Squalus lalannei'' Baranes, 2003 (Seychelles spurdog)
* '' Squalus lobularis'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (Atlantic lobefin dogfish) [
* '' Squalus megalops'' ( W. J. Macleay, 1881) (shortnose spurdog)
* '' Squalus melanurus'' Fourmanoir & Rivaton, 1979 (blacktailed spurdog)
* '' Squalus mitsukurii'' D. S. Jordan & Snyder, 1903 (shortspine spurdog)
* '' Squalus montalbani'' Whitley, 1931 (Indonesian greeneye spurdog)
* '' Squalus nasutus'' ]Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, L. J. Marshall & W. T. White, 2007 (western longnose spurdog)
* '' Squalus notocaudatus'' Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, W. T. White & J. D. Stevens, 2007 (bartail spurdog)
* '' Squalus quasimodo'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (humpback western dogfish) [
* '' Squalus rancureli'' Fourmanoir & Rivaton, 1979 (Cyrano spurdog)
* '' Squalus raoulensis'' Duffy & ]Last
A last is a mechanical form shaped like a human foot. It is used by shoemakers and cordwainers in the manufacture and repair of shoes. Lasts typically come in pairs and have been made from various materials, including hardwoods, cast iron, ...
, 2007 (Kermadec spiny dogfish)
*'' Squalus shiraii'' Viana & M. R. de Carvalho, 2020 (Shirai's spurdog) 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 sever ...
''
Image:Squalus altipinnis.jpg, ''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, o ...
''
Image:Squalus blainville.jpg, ''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 ...
''
Image:Squalus bucephalus JNC2621 Body.JPG, '' Squalus bucephalus''
Image:Squalus chloroculus.jpg, '' Squalus chloroculus''
Image:Squalus crassispinus.jpg, '' Squalus crassispinus''
Image:Squalus cubensis eits.jpg, '' Squalus cubensis''
Image:Squalus megalops.jpg, '' Squalus megalops''
Image:Squalus melanurus JNC2719 Body.JPG, '' Squalus melanurus''
Image:HutoTZ.jpg, '' Squalus mitsukurii''
See also
* List of prehistoric cartilaginous fish genera
References
{{Taxonbar, from=Q737224
Extant Campanian first appearances
Taxa named by Carl Linnaeus