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Requiem shark

Requiem sharks
Temporal range: Early Cretaceous to recent
Tiger shark.jpg
A tiger shark, Galeocerdo cuvier
Scientific classification
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Superorder: Selachimorpha
Order: Carcharhiniformes
Family: Carcharhinidae
D. S. Jordan & Evermann, 1896

Requiem sharks are sharks of the family Carcharhinidae in the order Carcharhiniformes, containing migratory, live-bearing sharks of warm seas (sometimes of brackish or fresh water) such as the spinner shark, the blacknose shark, the blacktip shark, the blacktail reef shark, and the blacktip reef shark.

The name may be related to the French word for shark, 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 verb reschignier ("to grimace while baring teeth").

Family members have the usual carcharhiniform characteristics. Their 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 small as 69 cm (2.26 ft) adult length in the Australian sharpnose shark, up to 5.5 m (18 ft) 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, a degree of inaccuracy exists in attack records.

The 60 species of requiem shark are grouped into 12 genera:

† = extinct


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