|A bull shark, Carcharhinus leucas|
There are currently 60 species of requiem sharks which are grouped into 12 genera. Some of the most familiar species in this family are the lemon shark, the blue shark, the tiger shark, the bull shark, and the whitetip reef shark.
Requiem sharks are found in temperate and tropical oceans, and many species are worldwide. Some live in the open ocean (oceanic whitetip shark), while some live in freshwater rivers and lakes (bull shark).
All species of requiem sharks have a head of normal shape. Their eyes have a nictitating (winking) membranes. They have caudal fins with the upper lobe being larger than the lower but not very long, two spineless dorsal fins, the first one usually much larger than the second in most of the Atlantic species, an anal fin, a caudal peduncle which doesn't have lateral keels, and sharp, bladelike teeth with a single cusp. 
Evolutionary history[change | change source]
The oldest member of the family is from the early Cretaceous of France. Only a few examples of the group are known from before the beginning of the Cenozoic. Modern carcharinid sharks have extensively diversified in coral reef habitats.
Genera[change | change source]
References[change | change source]
- "Facts about Requiem Sharks(Carcharhinidae)-Encyclopedia of Life". eol.org. Retrieved 22 June 2013.
- "Requiem sharks, family Carcharhinidae". gma.org. Retrieved 22 June 2013.
- "BBC Nature-Requiem sharks videos,news,and facts". bbc.co.uk. Archived from the original on 27 June 2013. Retrieved 22 June 2013.
- Guinot, Guillaume; Cappetta, Henri; Adnet, Sylvain (March 2014). "A rare elasmobranch assemblage from the Valanginian (Lower Cretaceous) of southern France". Cretaceous Research. 48: 54–84. doi:10.1016/j.cretres.2013.11.014.
- Gates, Terry A.; Gorscak, Eric; Makovicky, Peter J. (2019-01-22). "New sharks and other chondrichthyans from the latest Maastrichtian (Late Cretaceous) of North America". Journal of Paleontology. 93 (3): 512–530. doi:10.1017/jpa.2018.92. ISSN 0022-3360.
- Sorenson, L.; Santini, F.; Alfaro, M. E. (August 2014). "The effect of habitat on modern shark diversification". Journal of Evolutionary Biology. 27 (8): 1536–1548. doi:10.1111/jeb.12405.
- "Fish Identification". fishbase.org. Retrieved 22 June 2013.