View source for Requiem shark

{{Short description|Family of sharks}}
{{Automatic taxobox
| name = Requiem sharks
| fossil_range = {{fossilrange|Valanginian|Recent}}
| image = Blacktip reef shark (Georgia Aquarium) (cropped).jpg
| image_caption = [[Blacktip reef shark]]<br>(''Carcharhinus melanopterus'')
| taxon = Carcharhinidae
| authority = [[David Starr Jordan|D. S. Jordan]] & [[Barton Warren Evermann|Evermann]], 1896
}}{{Redirect-distinguish-text|Carcharhinidae|[[Carchariidae]]}}
'''Requiem sharks''' are [[shark]]s of the [[Family (biology)|family]] '''Carcharhinidae''' in the [[order (biology)|order]] [[Carcharhiniformes]]. They are [[Animal migration|migratory]], [[viviparity|live-bearing]] sharks of warm seas (sometimes of [[Brackish water|brackish]] or fresh water) and include such species as the [[bull shark]], [[lemon shark]], [[blacktip shark]], and [[whitetip reef shark]].

Family members have the usual carcharhiniform characteristics. Their eyes are round, and one or two [[gill]] slits fall over the [[pectoral fin]] base. Most species are [[viviparous]], the young being born fully developed. They vary widely in size, from as small as {{convert|69|cm|ft|abbr=on}} adult length in the [[Australian sharpnose shark]], up to {{convert|4|m|ft|abbr=on}} adult length in the [[oceanic whitetip shark]].<ref name=FB>Compagno, L.J.V. [http://www.fishbase.org/Summary/FamilySummary.php?ID=11 Family Carcharhinidae - Requiem sharks] in Froese, R. and D. Pauly. Editors. 2010. [http://www.fishbase.org FishBase]. World Wide Web electronic publication, version (10/2013).</ref> Scientists assume that the size and shape of their pectoral fins have the right dimensions to minimize transport cost.<ref>{{cite journal | pmc=5098981 | year=2016 | last1=Iosilevskii | first1=G. | last2=Papastamatiou | first2=Y. P. | title=Relations between morphology, buoyancy and energetics of requiem sharks | journal=Royal Society Open Science | volume=3 | issue=10 | article-number=160406 | doi=10.1098/rsos.160406 | pmid=27853556 | bibcode=2016RSOS....360406I }}</ref> Requiem sharks tend to live in more tropical areas, but tend to migrate. Females release a chemical in the ocean in order to let the males know they are ready to mate. Typical mating time for these sharks is around spring to autumn.<ref>{{Cite web|url=http://www.sharksider.com/introducing-requiem-sharks/|title=Introducing Requiem Sharks|date=22 August 2016}}</ref>

According to the [[International Shark Attack File|ISAF]], requiem sharks are among the top five species involved in [[shark attack]]s on humans;<ref>{{cite web |title=Species Implicated in Attacks |url=https://www.floridamuseum.ufl.edu/shark-attacks/factors/species-implicated/ |website=Florida Museum |date=24 January 2018 |access-date=2 June 2018}}</ref> however, "requiem shark" is not a single species, but refers, in this case, to an order of similar sharks that are often involved in incidents. ISAF prefers to use "requiem sharks" due to the difficulty in identifying individual species.<ref>[http://www.flmnh.ufl.edu/fish/sharks/statistics/species2.htm ISAF Statistics on Attacking Species of Shark<!-- Bot generated title -->] {{webarchive |url=https://web.archive.org/web/20090724033127/http://www.flmnh.ufl.edu/fish/Sharks/Statistics/species2.htm |date=July 24, 2009 }}</ref>

==Etymology==
The common name '''requiem shark''' may be related to the French word for shark, {{Lang|fr|requin}}, which is itself of disputed etymology. One derivation of the latter is from Latin ''[[requiem]]'' ("rest"), which would thereby create a cyclic etymology (''requiem-requin-requiem''), but other sources derive it from the Old French verb ''reschignier'' ("to grimace while baring teeth").

The scientific name '''Carcharhinidae''' was first proposed in 1896 by [[David Starr Jordan|D.S. Jordan]] and [[Barton Warren Evermann|B.W. Evermann]] as a subfamily of Galeidae (now replaced by "Carcharhinidae").<ref>Subfamily Carcharhininae Jordan & Evermann, 1896 (Family Galeidae), Bull.U.S.Nat.Mus., 48(1):28.</ref>{{Sfn|Compagno|1984|p=445}} The term is derived from Greek {{Lang|el|κάρχαρος}} (''karcharos'', sharp or jagged), and ῥί̄νη (''rhinē'', rasp); both elements describe the jagged, rasp-like skin.<ref>{{cite web |url=https://etyfish.org/carcharhiniformes/ |title=Order Carcharhiniformes (Ground Sharks): Families Pentanchidae, Scyliorhinidae, Proscylliidae, Pseudotriakidae, Leptochariidae, Triakidae, Hemigaleidae, Carcharhinidae and Sphyrnidae |last1=Scharpf |first1=Christopher |last2=Lazara |first2=Kenneth J. |website=The ETYFish Project |date=18 January 2013 |access-date=July 31, 2021 |archive-date=18 January 2022 |archive-url=https://web.archive.org/web/20220118100245/https://etyfish.org/carcharhiniformes/ }}</ref> Rasp-like skin is typical of [[Fish scale#Placoid scales|shark skin]] in general, and is not diagnostic to Carcharhinidae.

== Evolutionary history ==
The oldest member of the family is ''[[Archaeogaleus|Archaeogaleus lengadocensis]]'' from the [[Early Cretaceous]] ([[Valanginian]]) of France.<ref>{{Cite journal |last1=Guinot |first1=Guillaume |last2=Cappetta |first2=Henri |last3=Adnet |first3=Sylvain |date=March 2014 |title=A rare elasmobranch assemblage from the Valanginian (Lower Cretaceous) of southern France |url=https://linkinghub.elsevier.com/retrieve/pii/S0195667113001869 |journal=Cretaceous Research |language=en |volume=48 |pages=54–84 |doi=10.1016/j.cretres.2013.11.014|bibcode=2014CrRes..48...54G |url-access=subscription }}</ref> Only a handful of records of the group are known from prior to the beginning of the [[Cenozoic]].<ref>{{Cite journal |last1=Gates |first1=Terry A. |last2=Gorscak |first2=Eric |last3=Makovicky |first3=Peter J. |date=2019-01-22 |title=New sharks and other chondrichthyans from the latest Maastrichtian (Late Cretaceous) of North America |journal=Journal of Paleontology |volume=93 |issue=3 |pages=512–530 |doi=10.1017/jpa.2018.92 |bibcode=2019JPal...93..512G |s2cid=198159821 |issn=0022-3360|doi-access=free }}</ref> Modern carcharinid sharks have extensively diversified in [[coral reef]] habitats.<ref>{{Cite journal |last1=Sorenson |first1=L. |last2=Santini |first2=F. |last3=Alfaro |first3=M. E. |date=August 2014 |title=The effect of habitat on modern shark diversification |journal=Journal of Evolutionary Biology |language=en |volume=27 |issue=8 |pages=1536–1548 |doi=10.1111/jeb.12405|pmid=24890604 |doi-access=free }}</ref>

== Hunting strategies ==
Requiem sharks are extraordinarily fast and effective hunters. Their elongated, torpedo-shaped bodies make them quick and agile swimmers, so they can easily attack any prey. Some species are continually active, while others are capable of resting motionless for extended periods on the bottom. They have a range of food sources depending on location and species, including [[Osteichthyes|bony fish]], [[squid]], [[octopus]], [[lobster]], [[Turtle|turtles]], [[Marine mammal|marine mammals]], [[Seabird|seabirds]], other sharks and [[Batoidea|rays]]; smaller species tend to select a narrow range of prey, but some very large species, especially the [[tiger shark]] (Galeocerdo cuvier), are virtually omnivorous.{{Sfn|Compagno|1984|p=445}} They are often considered the "garbage cans" of the seas because they will eat almost anything, even non-food items like trash.{{Sfn|Compagno|1984|p=445}} They are migratory hunters that follow their food source across entire oceans. They tend to be most active at night time,{{Sfn|Compagno|1984|p=445}} where their impressive eyesight can help them sneak up on unsuspecting prey. It is worth mentioning that the tiger shark, however, possibly belongs to the [[Galeocerdonidae|Galeocerdidae]] family.<ref>Pollerspöck, J.; Straube, N. Bibliography Database of Living/Fossil Sharks, Rays and Chimaeras (Chondrichtyes: Elasmobranchii, Holocephali)—List of Valid Extant Species; List of Described Extant Species; Statistic, World Wide Web Electronic Publication, Version 10/2021; {{ISSN|2195-6499}}. Available online: www.shark-references.com (accessed on 23 November 2021).</ref> Most requiem sharks hunt alone, however some species like the [[whitetip reef shark]]s and [[lemon shark]]s are cooperative feeders and will hunt in packs through coordinated, timed attacks against their prey. Some of the species have been shown to give specialized displays when confronted by divers or other sharks, which may be indicative of aggressive or defensive threat.{{Sfn|Compagno|1984|p=445}}

==Classification==
The 60 species of requiem shark are grouped into 11 genera:<ref name=FB/>
* Genus ''[[Scoliodon]]'' <small>[[Johannes Peter Müller|J. P. Müller]] & [[Friedrich Gustav Jakob Henle|Henle]], 1838</small>
** ''[[Spadenose shark|Scoliodon laticaudus]]'' <small>J. P. Müller & Henle, 1838</small> (spadenose shark)
** ''[[Pacific spadenose shark|Scoliodon macrorhynchos]]'' <small>[[Pieter Bleeker|Bleeker]], 1852</small> (Pacific spadenose shark)
* Genus ''[[Carcharhinus]]'' <small>[[Henri Marie Ducrotay de Blainville|Blainville]], 1816</small>
**''[[Blacknose shark|Carcharhinus acronotus]]'' <small>[[Felipe Poey y Aloy|Poey]], 1860</small> (blacknose shark)<span style="{{MirrorH}}">[[File:Blacknose shark (Duane Raver).png|80 px]]</span>
** ''[[Silvertip shark|Carcharhinus albimarginatus]]'' <small>[[Eduard Rüppell|Rüppell]], 1837</small> (silvertip shark)
** ''[[Bignose shark|Carcharhinus altimus]]'' <small>[[Stewart Springer|S. Springer]], 1950</small> (bignose shark)
** ''[[Graceful shark|Carcharhinus amblyrhynchoides]]'' <small>[[Gilbert Percy Whitley|Whitley]], 1934</small> (graceful shark)
** ''[[Grey reef shark|Carcharhinus amblyrhynchos]]'' <small>Bleeker, 1856</small> (grey reef shark)
** ''[[Pigeye shark|Carcharhinus amboinensis]]'' <small>J. P. Müller & Henle, 1839</small> (pigeye shark)
** ''[[Borneo shark|Carcharhinus borneensis]]'' <small>Bleeker, 1858</small> (Borneo shark)
** ''[[Copper shark|Carcharhinus brachyurus]]'' <small>[[Albert Günther|Günther]], 1870</small> (copper shark)
** [[File:Spinner shark nmfs.jpg|thumb|253px|right|[[Spinner shark]], ''Carcharhinus brevipinna'', from the Gulf of Mexico]]''[[Spinner shark|Carcharhinus brevipinna]]'' <small>J. P. Müller & Henle, 1839</small> (spinner shark)<span style="{{MirrorH}}">[[File:Spinner shark (Duane Raver).png|80 px]]</span>
** ''[[Nervous shark|Carcharhinus cautus]]'' <small>Whitley, 1945</small> (nervous shark)
** ''[[Pacific smalltail shark|Carcharhinus cerdale]]'' <small>[[Charles Henry Gilbert|C. H. Gilbert]], 1898</small> (Pacific smalltail shark)
** ''[[Carcharhinus coatesi]]'' <small>Whitley, 1939</small> (Coates's shark)
** ''[[Whitecheek shark|Carcharhinus dussumieri]]'' <small>J. P. Müller & Henle, 1839</small> (whitecheek shark)
** ''[[Silky shark|Carcharhinus falciformis]]'' <small>J. P. Müller & Henle, 1839</small> (silky shark)<span style="{{MirrorH}}">[[File:Silky shark (Duane Raver).png|80 px]]</span>
** ''[[Creek whaler|Carcharhinus fitzroyensis]]'' <small>Whitley, 1943</small> (creek whaler)
** [[File:Galapagos shark.jpg|thumb|253px|right|[[Galapagos shark]], ''Carcharhinus galapagensis'']]''[[Galapagos shark|Carcharhinus galapagensis]]'' <small>[[Robert Evans Snodgrass|Snodgrass]] & [[Edmund Heller|Heller]], 1905</small> (Galapagos shark)
** ''[[Pondicherry shark|Carcharhinus hemiodon]]'' <small>J. P. Müller & Henle, 1839</small> (Pondicherry shark)
** ''[[Carcharhinus humani]]'' <small>[[William Toby White|W. T. White]] & [[Simon Weigmann|Weigmann]], 2014</small> (Human's whaler shark)
** ''[[Finetooth shark|Carcharhinus isodon]]'' <small>J. P. Müller & Henle, 1839</small> (finetooth shark)
** ''[[Smoothtooth blacktip shark|Carcharhinus leiodon]]'' <small>[[Jack Garrick|Garrick]], 1985</small> (smoothtooth blacktip shark)
** ''[[Bull shark|Carcharhinus leucas]]'' <small>J. P. Müller & Henle, 1839</small> (bull shark)<span style="{{MirrorH}}">[[File:Bull shark (Duane Raver).png|80 px]]</span>
** ''[[Blacktip shark|Carcharhinus limbatus]]'' <small>J. P. Müller & Henle, 1839</small> (blacktip shark)<span style="{{MirrorH}}">[[File:Blacktip shark (Duane Raver).png|80 px]]</span>
** ''[[Oceanic whitetip shark|Carcharhinus longimanus]]'' <small>Poey, 1861</small> (oceanic whitetip shark)<span style="{{MirrorH}}">[[File:Oceanic whitetip shark (Duane Raver).png|80 px]]</span>
** ''[[Hardnose shark|Carcharhinus macloti]]'' <small>J. P. Müller & Henle, 1839</small> (hardnose shark)
** ''[[Blacktip reef shark|Carcharhinus melanopterus]]'' <small>[[Jean René Constant Quoy|Quoy]] & [[Joseph Paul Gaimard|Gaimard]], 1824</small> (blacktip reef shark)
** ''[[Dusky shark|Carcharhinus obscurus]]'' <small>[[Charles Alexandre Lesueur|Lesueur]], 1818</small> (dusky shark)<span style="{{MirrorH}}">[[File:Dusky shark (Duane Raver).png|80 px]]</span>
** ''[[Daggernose shark|Carcharhinus oxyrhynchus]]'' <small>J. P. Müller & Henle, 1839</small> (daggernose shark) [[File:Carcharias oxyrhynchus by muller and henle.png|80 px]]
** ''[[Caribbean reef shark|Carcharhinus perezi]]'' <small>[[Felipe Poey y Aloy|Poey]], 1876</small> (Caribbean reef shark)
** ''[[Sandbar shark|Carcharhinus plumbeus]]'' <small>[[Giovanni Domenico Nardo|Nardo]], 1827</small> (sandbar shark)<span style="{{MirrorH}}">[[File:Sandbar shark (Duane Raver).png|80 px]]</span>
** ''[[Smalltail shark|Carcharhinus porosus]]'' <small>[[Camillo Ranzani|Ranzani]], 1839</small> (smalltail shark)
** ''[[Blackspot shark|Carcharhinus sealei]]'' <small>[[Viktor Pietschmann|Pietschmann]], 1913</small> (blackspot shark)
** ''[[Night shark|Carcharhinus signatus]]'' <small>Poey, 1868</small> (night shark)
** ''[[Spot-tail shark|Carcharhinus sorrah]]'' <small>J. P. Müller & Henle, 1839</small> (spot-tail shark)[[File:Carcharias_sorrah_by_muller_and_henle.png|80px]]
** ''[[Australian blacktip shark|Carcharhinus tilstoni]]'' <small>Whitley, 1950</small> (Australian blacktip shark)
** †''[[Carcharhinus tingae]]''<ref>{{Cite news|title=Extinct shark named after LSU museum official as she retires|language=en-US|newspaper=Washington Post|url=https://www.washingtonpost.com/national/extinct-shark-named-after-lsu-museum-official-as-she-retires/2021/12/24/2e033f26-64e4-11ec-9b51-7131fa190c5e_story.html|access-date=2021-12-25|issn=0190-8286}}</ref>
** ''[[Carcharhinus tjutjot]]'' <small>Bleeker, 1852</small> (Indonesian whaler shark)
** ''[[Carcharhinus obsolerus]]'' <small>[[William T. White|White]], [[Peter M. Kyne|Kyne]], and [[Mark Harris (biologist)|Harris]], 2019 </small>(lost shark)
* Genus ''[[River shark|Glyphis]]'' <small>[[Louis Agassiz|Agassiz]], 1843</small>
** ''[[Ganges shark|Glyphis gangeticus]]'' <small>J. P. Müller & Henle, 1839</small> (Ganges shark)
** ''[[Northern river shark|Glyphis garricki]]'' <small>Compagno, W. T. White & Last, 2008</small> (northern river shark)
** ''[[Speartooth shark|Glyphis glyphis]]'' <small>J. P. Müller & Henle, 1839</small> (speartooth shark)
** ''[[Glyphis (shark)|Glyphis]]'' sp. <small>not yet described</small> (Mukah river shark)
* Genus ''[[Lamiopsis]]'' <small>[[Theodore Gill|Gill]], 1862</small>
** ''[[Broadfin shark|Lamiopsis temminckii]]'' <small>J. P. Müller & Henle, 1839</small> (broadfin shark)
** ''[[Borneo broadfin shark|Lamiopsis tephrodes]]'' <small>Fowler, 1905</small> (Borneo broadfin shark)
* Genus ''[[Whitenose shark|Nasolamia]]'' <small>Compagno & Garrick, 1983</small>
** ''[[Whitenose shark|Nasolamia velox]]'' <small>C. H. Gilbert, 1898</small> (whitenose shark)
* Genus ''[[Negaprion]]'' <small>Whitley, 1940</small>
** [[File:Wikilemon Nbrevirostris1 TerryGoss.jpg|thumb|253px|right|[[Lemon shark]], ''Negaprion brevirostris'', at Tiger Beach, [[The Bahamas|Bahamas]]]]''[[Sicklefin lemon shark|Negaprion acutidens]]'' <small>Rüppell, 1837</small> (sicklefin lemon shark)
** ''[[Lemon shark|Negaprion brevirostris]]'' <small>Poey, 1868</small> (lemon shark)<span style="{{MirrorH}}">[[File:Lemon shark (Duane Raver).png|80 px]]</span>
** †''[[Negaprion eurybathrodon]]'' <small>Blake, 1862</small>
* Genus ''[[Blue shark|Prionace]]'' <small>[[Theodore Edward Cantor|Cantor]], 1849</small>
** [[File:Prionace glauca by mark conlin.JPG|thumb|253px|right|[[Blue shark]], ''Prionace glauca'']]''[[Blue shark|Prionace glauca]]'' <small>[[Carl Linnaeus|Linnaeus]], [[10th edition of Systema Naturae|1758]]</small> (blue shark) <span style="{{MirrorH}}">[[File:Prionace glauc.JPG|80 px]]</span>
* Genus ''[[Rhizoprionodon]]'' <small>Whitley, 1929</small>
** ''[[Milk shark|Rhizoprionodon acutus]]'' <small>Rüppell, 1837</small> (milk shark)
** ''[[Brazilian sharpnose shark|Rhizoprionodon lalandii]]'' <small>J. P. Müller & Henle, 1839</small> (Brazilian sharpnose shark)
** ''[[Pacific sharpnose shark|Rhizoprionodon longurio]]'' <small>[[David Starr Jordan|D. S. Jordan]] & C. H. Gilbert, 1882</small> (Pacific sharpnose shark)
** ''[[Grey sharpnose shark|Rhizoprionodon oligolinx]]'' <small>[[Victor Gruschka Springer|V. G. Springer]], 1964</small> (grey sharpnose shark)
** ''[[Caribbean sharpnose shark|Rhizoprionodon porosus]]'' <small>Poey, 1861</small> (Caribbean sharpnose shark)
** ''[[Australian sharpnose shark|Rhizoprionodon taylori]]'' <small>[[James Douglas Ogilby|Ogilby]], 1915</small> (Australian sharpnose shark)
** ''[[Atlantic sharpnose shark|Rhizoprionodon terraenovae]]'' <small>[[John Richardson (naturalist)|J. Richardson]], 1836</small> (Atlantic sharpnose shark)
* Genus ''[[Sliteye shark|Loxodon]]'' <small>J. P. Müller & Henle, 1838</small>
** ''[[Sliteye shark|Loxodon macrorhinus]]'' <small>J. P. Müller & Henle, 1839</small> (sliteye shark)
* Genus ''[[Whitetip reef shark|Triaenodon]]'' <small>J. P. Müller & Henle, 1837</small>
** ''[[Whitetip reef shark|Triaenodon obesus]]'' <small>Rüppell, 1837</small> (whitetip reef shark)
* Genus †''[[Physogaleus]]'' <small>Cappetta, 1980</small><ref>{{cite journal|date=March 2022|author=D. J. Cicimurri, J. L. Knight, J. A. Ebersole|title=Early Oligocene (Rupelian) fishes (Chondrichthyes, Osteichthyes) from the Ashley Formation (Cooper Group) of South Carolina, USA|journal=PaleoBios|volume=39|issue=1|pages=1–38|doi=10.5070/P939056976|doi-access=free}}</ref>
** †''Physogaleus americanus'' <small>Case, 1994</small>
** †''Physogaleus contortus'' <small>Gibbes, 1849</small>
** †''Physogaleus hemmooriensis'' <small>Reinecke & Hoedemakers, 2006</small>
** †''Physogaleus huberensis'' <small>Case, 1981</small>
** †''Physogaleus latecuspidatus'' <small>Muller, 1999</small>
** †''Physogaleus latus'' <small>Storms, 1894</small>
** †''Physogaleus maltzani'' <small>Winkler, 1875</small>
** †''Physogaleus onkensis'' <small>Boulemia & Adnet, 2023</small>
** †''Physogaleus rosehillensis'' <small>Case & Borodin, 2000</small>
** †''Physogaleus secundus'' <small>Winkler, 1876</small>
** †''Physogaleus tertius'' <small>Winkler, 1876</small>
<small>† = extinct</small>

==See also==
* [[Freshwater shark]]

==References==
{{Reflist}}
==Sources==
{{cite book |last=Compagno |first=Leonard J.V. |year=1984 |location=Rome |title=FAO species catalogue Vol.4. Sharks of the world. An annotated and illustrated catalogue of shark species known to date. Part 2. Carcharhiniformes|publisher=[[Food and Agriculture Organization of the United Nations]] |isbn=92-5-101383-7 |url=https://www.fao.org/3/ad123e/AD123e24.pdf}}
==External links==
{{Commons category}}

* [https://web.archive.org/web/20090312093046/http://bajolagua.es/Tiburones/index.html Requiem Shark Photo Gallery] ([[Bahamas]])
* [http://www.elasmo-research.org Elasmo-research]
* [https://www.floridamuseum.ufl.edu/shark-attacks/factors/species-implicated/ International Shark Attack File]

{{Carcharhiniformes}}
{{Carcharhinidae}}
{{Taxonbar|from=Q48191}}
{{Authority control}}

[[Category:Carcharhinidae| ]]
[[Category:Taxa named by David Starr Jordan]]
[[Category:Taxa named by Barton Warren Evermann]]
[[Category:Extant Valanginian first appearances]]