Carcharhiniformes

Requiem sharks
Temporal range: Bathonian–present
A finetooth shark, Carcharhinus isodon
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Class: Chondrichthyes
Subclass: Elasmobranchii
Division: Selachii
Superorder: Galeomorphii
Order: Carcharhiniformes
Compagno, 1977
Ground sharks, like this blacknose shark, have a nictitating membrane which can be drawn over the eye to protect it.

Carcharhiniformes /kɑːrkəˈraɪnɪfɔːrmiːz/, the Requiem sharks, are the largest order of sharks, with over 270 species. They include a number of common types, such as catsharks, swellsharks, and requiem sharks.

Members of this order are characterized by the presence of a nictitating membrane over the eye, two dorsal fins, an anal fin, and five gill slits.

The families in the order Carcharhiniformes are expected to be revised; recent DNA studies show that some of the conventional groups are not monophyletic.

The oldest members of the order appeared during the Middle-Late Jurassic, which have teeth and body forms that are morphologically similar to living catsharks.[1] Carchariniformes first underwent major diversification during the Late Cretaceous, initially as mostly small-sized forms, before radiating into medium and large body sizes during the Cenozoic.[2][3]

  1. ^ Stumpf, Sebastian; Scheer, Udo; Kriwet, Jürgen (2019-03-04). "A new genus and species of extinct ground shark, †Diprosopovenator hilperti, gen. et sp. nov. (Carcharhiniformes, †Pseudoscyliorhinidae, fam. nov.), from the Upper Cretaceous of Germany". Journal of Vertebrate Paleontology. 39 (2): e1593185. Bibcode:2019JVPal..39E3185S. doi:10.1080/02724634.2019.1593185. ISSN 0272-4634. S2CID 155785248.
  2. ^ Condamine, Fabien L.; Romieu, Jules; Guinot, Guillaume (2019-10-08). "Climate cooling and clade competition likely drove the decline of lamniform sharks". Proceedings of the National Academy of Sciences. 116 (41): 20584–20590. Bibcode:2019PNAS..11620584C. doi:10.1073/pnas.1902693116. ISSN 0027-8424. PMC 6789557. PMID 31548392.
  3. ^ Brée, Baptiste; Condamine, Fabien L.; Guinot, Guillaume (2022-12-19). "Combining palaeontological and neontological data shows a delayed diversification burst of carcharhiniform sharks likely mediated by environmental change". Scientific Reports. 12 (1): 21906. Bibcode:2022NatSR..1221906B. doi:10.1038/s41598-022-26010-7. ISSN 2045-2322. PMC 9763247. PMID 36535995.