Requiem shark

Requiem sharks are a family, Carcharhinidae, of sharks in the order Carcharhiniformes, containing migratory, live-bearing sharks of warm seas (sometimes of brackish or fresh water) such as the tiger shark, the blue shark, the bull shark, and the milk shark.

The name may be related to the French word for shark, requin, itself of disputed etymology (chien de mer or Latin requiem ("rest"), which would thereby create a cyclic etymology: requiem-requin-requiem.

Family members have the usual carcharhiniform characteristics. The eyes are round, and the pectoral fins are completely behind the five gill slits. Most species are viviparous, the young being born fully developed. They vary widely in size, from as little as 69 cm adult length in the Australian sharpnose shark, up to 5.5 m adult length in the tiger shark.

Requiem sharks are responsible for a large proportion of attacks on humans; however, due to the difficulty in identifying individual species, there is a degree of inaccuracy in attack records.

Classification
The 52 species of requiem shark are grouped into 12 genera:

Family Carcharhinidae
 * Subfamily Galeocerdinae
 * Genus Galeocerdo J. P. Müller & Henle, 1837
 * Galeocerdo cuvier (Péron & Lesueur, 1822) (Tiger shark)
 * Subfamily Scoliodontinae
 * Genus Scoliodon J. P. Müller & Henle, 1838
 * Scoliodon laticaudus J. P. Müller & Henle, 1838 (Spadenose shark)
 * Subfamily Carcharhininae
 * Tribe Carcharhinini
 * Genus Carcharhinus Blainville, 1816
 * Carcharhinus acronotus (Poey, 1860) (Blacknose shark)
 * Carcharhinus albimarginatus (Rüppell, 1837) (Silvertip shark)
 * Carcharhinus altimus (S. Springer, 1950) (Bignose shark)
 * Carcharhinus amblyrhynchoides (Whitley, 1934) (Graceful shark)
 * Carcharhinus amblyrhynchos (Bleeker, 1856) (Grey or blacktail reef shark)
 * Carcharhinus amboinensis (J. P. Müller & Henle, 1839) (Pigeye shark)
 * Carcharhinus borneensis (Bleeker, 1858) (Borneo shark)
 * Carcharhinus brachyurus (Günther, 1870) (Copper shark)
 * Carcharhinus brevipinna (J. P. Müller & Henle, 1839) (Spinner shark)
 * Carcharhinus cautus (Whitley, 1945) (Nervous shark)
 * Carcharhinus dussumieri (J. P. Müller & Henle, 1839) (Whitecheek shark)
 * Carcharhinus falciformis (J. P. Müller & Henle, 1839) (Silky shark)
 * Carcharhinus fitzroyensis (Whitley, 1943) (Creek whaler)
 * Carcharhinus galapagensis (Snodgrass & Heller, 1905) (Galapagos shark)
 * Carcharhinus hemiodon (Valenciennes in J. P. Müller & Henle, 1839) (Pondicherry shark)
 * Carcharhinus isodon (J. P. Müller & Henle, 1839) (Finetooth shark)
 * Carcharhinus leiodon Garrick, 1985 (Smooth tooth blacktip shark )
 * Carcharhinus leucas (J. P. Müller & Henle, 1839) (Bull shark)
 * Carcharhinus limbatus (J. P. Müller & Henle, 1839) (Blacktip shark)
 * Carcharhinus longimanus (Poey, 1861) (Oceanic whitetip shark)
 * Carcharhinus macloti (J. P. Müller & Henle, 1839) (Hardnose shark)
 * Carcharhinus macrops J. X. Liu, 1983
 * Carcharhinus melanopterus (Quoy & Gaimard, 1824) (Blacktip reef shark)
 * Carcharhinus obscurus (Lesueur, 1818) (Dusky shark)
 * Carcharhinus perezii (Poey, 1876) (Caribbean reef shark)
 * Carcharhinus plumbeus (Nardo, 1827) (Sandbar shark)
 * Carcharhinus porosus (Ranzani, 1839) (Smalltail shark)
 * Carcharhinus sealei (Pietschmann, 1913) (Blackspot shark)
 * Carcharhinus signatus (Poey, 1868) (Night shark)
 * Carcharhinus sorrah (J. P. Müller & Henle, 1839) (Spot-tail shark)
 * Carcharhinus tilstoni (Whitley, 1950) (Australian blacktip shark)
 * Genus Glyphis Agassiz, 1843
 * Glyphis fowlerae Compagno, W. T. White & Cavanagh, 2010 (Borneo river shark)
 * Glyphis gangeticus (J. P. Müller & Henle, 1839) (Ganges shark)
 * Glyphis garricki Compagno, W. T. White & Last, 2008 (Northern river shark)
 * Glyphis glyphis (J. P. Müller & Henle, 1839) (Speartooth shark)
 * Glyphis siamensis (Steindachner, 1896) (Irrawaddy river shark)
 * Genus Lamiopsis Gill, 1862
 * Lamiopsis temminckii (J. P. Müller & Henle, 1839) (Broadfin shark)
 * Genus Nasolamia Compagno & Garrick, 1983
 * Nasolamia velox (Gilbert, 1898) (Whitenose shark)
 * Genus Negaprion Whitley, 1940
 * Negaprion acutidens (Rüppell, 1837) (Sicklefin lemon shark)
 * Negaprion brevirostris (Poey, 1868) (Lemon shark)
 * Genus Prionace Cantor, 1849
 * Prionace glauca (Linnaeus, 1758) (Blue shark)
 * Tribe Rhizoprionodontini
 * Genus Rhizoprionodon Whitley, 1929
 * Rhizoprionodon acutus (Rüppell, 1837) (Milk shark)
 * Rhizoprionodon lalandii (J. P. Müller & Henle, 1839) (Brazilian sharpnose shark)
 * Rhizoprionodon longurio (D. S. Jordan & Gilbert, 1882) (Pacific sharpnose shark)
 * Rhizoprionodon oligolinx V. G. Springer, 1964 (Grey sharpnose shark)
 * Rhizoprionodon porosus (Poey, 1861) (Caribbean sharpnose shark)
 * Rhizoprionodon taylori (Ogilby, 1915) (Australian sharpnose shark)
 * Rhizoprionodon terraenovae (J. Richardson, 1836) (Atlantic sharpnose shark)
 * Genus Loxodon J. P. Müller & Henle, 1838
 * Loxodon macrorhinus (J. P. Müller & Henle, 1839) (Sliteye shark)
 * Tribe Isogomphodontini
 * Genus Isogomphodon Gill, 1862
 * Isogomphodon oxyrhynchus (J. P. Müller & Henle, 1839) (Daggernose shark)
 * Tribe Triaenodontini
 * Genus Triaenodon J. P. Müller & Henle, 1837
 * Triaenodon obesus (Rüppell, 1837) (Whitetip reef shark)