Spurdog

{{Short description|Genus of sharks}} {{Redirect|Squalus|the submarine called ''Squalus''|USS Sailfish (SS-192){{!}}USS ''Sailfish'' (SS-192)}} {{Automatic taxobox | name = Spurdogs | fossil_range = {{fossil_range|89.8|0}} Campanian to Present<ref>{{cite journal | last = Sepkoski | first = J.J.Jr | title = A Compendium of Fossil Marine Animal Genera | journal = Bulletins of American Paleontology | volume = 363 | pages = 1–560 | year = 2002 | url =http://strata.geology.wisc.edu/jack/showgenera.php?taxon=575&rank=class }}</ref> | image = Squalus_acanthias2.jpg | image_caption = Spiny dogfish (''Squalus acanthias'') | taxon = Squalus | authority = Linnaeus, 1758 | type_species = ''Squalus acanthias'' | type_species_authority = Linnaeus, 1758 | synonyms = * ''Squalis'' Radermacher, 1779 (Missp.) * ''Acanthorhinus'' de Blainville, 1816 * ''Acanthias'' Leach, 1818<ref>[https://www.zoobank.org/NomenclaturalActs/fdc38a6a-2af0-45cc-a232-d4443e412ea2 ZooBank: ''Acanthias'' Leach, 1818]</ref> * ''Flakeus'' Whitley, 1939<ref>[https://www.zoobank.org/NomenclaturalActs/67730d84-00b8-4127-94fb-0a63adcda3c4 ZooBank: ''Flakeus'' Whitley, 1939]</ref> * ''Koinga'' Whitley, 1939<ref>[https://www.zoobank.org/NomenclaturalActs/c3b75939-91bc-4225-9c97-c768aff2a8b0 ZooBank: ''Koinga'' Whitley, 1939]</ref> }}

'''''Squalus''''' is a genus of dogfish sharks in the family Squalidae. Commonly known as '''spurdogs''', these sharks are characterized by smooth dorsal fin spines, teeth in upper and lower 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.<ref name=Wilga2007>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.''</ref>

The name comes from ''squalus'', the Latin for shark; this word is the root for numerous words related to sharks such as squaline and scientific names for sharks, such as the order Squaliformes.

==Species== Currently, 41 recognized species are placed in this genus: * ''Squalus acanthias'' Linnaeus, 1758 (spiny dogfish)<ref name=Viana2016a /> * ''Squalus acutipinnis'' Regan, 1908 (bluntnose spurdog) * ''Squalus acutirostris'' Chu, Meng & Li, 1984 (Chinese shortnose spurdog) * ''Squalus albicaudus'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (Brazilian whitetail dogfish)<ref name=Viana2016a>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.</ref> * ''Squalus albifrons'' Last, W. T. White & J. D. Stevens, 2007 (eastern highfin spurdog) * ''Squalus altipinnis'' Last, W. T. White & J. D. Stevens, 2007 (western highfin spurdog) * ''Squalus bahiensis'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (northeastern Brazilian dogfish)<ref name=Viana2016a /> * ''Squalus bassi'' Viana, De Carvalho & Ebert, 2017 (long-snouted African spurdog) * ''Squalus blainville'' (A. Risso, 1827) (longnose spurdog) * ''Squalus boretzi'' Dolganov, 2019 (emperor dogfish) * ''Squalus brevirostris'' S. Tanaka (I), 1917 (Japanese shortnose spurdog) * ''Squalus bucephalus'' Last, Séret & Pogonoski, 2007 (bighead spurdog) * ''Squalus chloroculus'' Last, W. T. White & Motomura, 2007 (greeneye spurdog) * ''Squalus clarkae'' Pfleger, Grubbs, Cotton & Daly-Engel, 2018 (Genie's dogfish) * ''Squalus crassispinus'' Last, M. J. Edmunds & Yearsley, 2007 (fatspine spurdog) * ''Squalus cubensis'' Howell-Rivero, 1936 (Cuban dogfish) * ''Squalus edmundsi'' W. T. White, Last & J. D. Stevens, 2007 (Edmund's spurdog) * ''Squalus formosus'' W. T. White & Iglésias, 2011 (Taiwan spurdog) * ''Squalus grahami'' W. T. White, Last & J. D. Stevens, 2007 (eastern longnose spurdog) * ''Squalus griffini'' Phillipps, 1931 (northern spiny dogfish) * ''Squalus hawaiiensis'' Daly-Engel, Koch, Anderson, Cotton, Grubbs, 2018 (Hawaiian spurdog) * ''Squalus hemipinnis'' W. T. White, Last & Yearsley, 2007 (Indonesian shortsnout spurdog) * ''Squalus hima'' Swetha, Bineesh, Beira, Das, & Bhaskar, 2024<ref>{{cite journal|url=https://shark-references.com/species/view/Squalus-hima?fbclid=IwZXh0bgNhZW0CMTAAAR0hKUSTvqR3HbgdFIewGA-s3TZRScgiLZAaXMpF8qrxTXmwt2JhwuKv6Fo_aem_P5WEh5GEfCzr-vGC_S00Aw|title=''Squalus hima'' Sweta & Bineesh, 2024|website=Shark-References.com}}</ref> (Indian 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)<ref name=Viana2016a /> * ''Squalus longispinis'' Fricke, Durville, Potin & Mulochau, 2023 (La Réunion longspine spurdog) * ''Squalus mahia'' Viana, Lisher & De Carvalho, 2017 (Malagasy skinny spurdog) * ''Squalus margaretsmithae'' Viana, Lisher & De Carvalho, 2017 (Smith's dogfish shark) * ''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, L. J. Marshall & W. T. White, 2007 (western longnose spurdog) * ''Squalus notocaudatus'' Last, W. T. White & J. D. Stevens, 2007 (bartail spurdog) * ''Squalus probatovi'' Myagkov & Kondyurin, 1986 (southern dogfish) * ''Squalus quasimodo'' Viana, M. R. de Carvalho & U. L. Gomes, 2016 (humpback western dogfish)<ref name=Viana2016a /> * ''Squalus rancureli'' Fourmanoir & Rivaton, 1979 (Cyrano spurdog) * ''Squalus raoulensis'' Duffy & Last, 2007 (Kermadec spiny dogfish) * ''Squalus shiraii'' Viana & M. R. de Carvalho, 2020 (Shirai's spurdog)<ref>{{Cite journal|last1=Viana|first1=Sarah T. F. L.|last2=Carvalho|first2=Marcelo R. de|date=2020-10-06|title=Squalus shiraii sp. nov. (Squaliformes, Squalidae), a new species of dogfish shark from Japan with regional nominal species revisited|url=https://zse.pensoft.net/article/51962/|journal=Zoosystematics and Evolution|language=en|volume=96|issue=2|pages=275–311|doi=10.3897/zse.96.51962|issn=1860-0743|doi-access=free}}</ref> * ''Squalus suckleyi'' (Girard, 1855) (Pacific spiny dogfish)

<gallery style="text-align:center;" mode="packed"> File:Spiny dogfish.jpg|''Squalus suckleyi'' File:Squalus altipinnis.jpg|''Squalus altipinnis'' File:Squalus blainville.jpg|''Squalus blainville'' File:Squalus bucephalus JNC2621 Body.JPG|''Squalus bucephalus'' File:Squalus chloroculus.jpg|''Squalus chloroculus'' File:Squalus crassispinus.jpg|''Squalus crassispinus'' File:Squalus cubensis eits.jpg|''Squalus cubensis'' File:Squalus megalops.jpg|''Squalus megalops'' File:Squalus melanurus JNC2719 Body.JPG|''Squalus melanurus'' File:HutoTZ.jpg|''Squalus mitsukurii'' </gallery>

==References== {{Reflist}}

Category:Squalus Category:Extant Campanian first appearances Category:Animal taxa named by Carl Linnaeus