Mackerel sharks
| Mackerel sharks | ||||||||||||
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Great White Shark ( Carcharodon carcharias ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Lamnidae | ||||||||||||
| Müller & Henle , 1838 |
The mackerel shark family (Lamnidae) is widespread worldwide and currently consists of three genera with a total of five species, the best known of which is the great white shark ( Carcharodon carcharias ). What they all have in common is the streamlined body shape that makes them fast swimmers. This is also favored by side keels at the base of the caudal fin , which do not have a notch, and a system of capillary vessels ( rete mirabile - "miracle network") that keeps the body temperature stable.
All jack sharks have a very pointed snout, very dark eyes and relatively large pectoral fins. All species are ovoviviparous , which means that they do form eggs, but these are hatched in the mother's body, which often leads to intrauterine cannibalism ( oophagia ).
All jack sharks are able to maintain their body temperature above that of the surrounding sea water. They have a blood vessel system, a fine network of veins (miracle network or rete mirabilis), which warms up the cold blood coming from the gills with the warm blood coming from the body. This increase in body temperature through the very efficient heat exchange system enables very high swimming speeds and the hunt for the marine mammals that live in colder regions.
Systematics
- Genus: Carcharodon
Smith in Müller & Henle , 1838
- Great white shark ( Carcharodon carcharias ( Linnaeus , 1758) )
- Genus: Mako sharks ( Isurus Rafinesque , 1810 )
- Short-finned Mako ( Isurus oxyrinchus rafinesque , 1810 )
- Long-finned Mako ( Isurus paucus Guitart Manday, 1966 )
- Genus: Herring sharks ( Lamna Cuvier , 1816 )
Originally the fossil- handed species megalodon ( Otodus megalodon ( Agassiz , 1835) , syn .: Carcharodon megalodon ) from the Miocene and Lower Pleistocene 5 to 1.6 million years ago was also assigned to this family. It is the largest known shark in the history of the earth - on average it reached a length of 12 to 14 meters. The genus Otodus and thus also Megalodon, however, is currently mostly assigned to the family Otodontidae .
literature
- Kurt Fiedler: Textbook of Special Zoology. Volume 2, Part 2: Fish. Gustav Fischer Verlag Jena, 1991, ISBN 3-334-00339-6 .
- Joseph S. Nelson : Fishes of the World. John Wiley & Sons, 2006, ISBN 0-471-25031-7 .
Web links
- Mackerel Sharks on Fishbase.org (English)