Real alligators
| Real alligators | ||||||||||||
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Mississippi alligator ( Alligator mississippiensis ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| alligator | ||||||||||||
| Cuvier , 1807 |
The real alligators ( Alligator ) are a kind of the family of the alligators (Alligatoridae). Within this they are compared to the caimans (Caimaninae) as the only recent representatives of the subfamily Alligatorinae .
features
In contrast to caimans, real alligators have a broad, flat snout and a bony septum . They also have six conical scales on the neck.
Way of life
Male alligators prefer large open, deep waters outside of the mating season, while females prefer shallower, smaller still waters. During the mating season, the males defend their territories by barking noises, hitting their heads on the water, and fighting with competitors.
Real alligators are those crocodiles whose range in North America and China extends furthest north to temperate latitudes, so that they are the only crocodiles to be confronted with frost in winter . They spend the winter buried in the bank mud or in deep water with a significantly reduced metabolism , but have to come to the surface regularly to breathe and sunbathe on the bank on warmer days. The Mississippi alligator can even hibernate in over-freezing waters, with its body remaining in the water while its snout reaches through the ice to breathe.
Systematics
The genus of real alligators includes the following two recent species :
| German name | Scientific name | distribution | Hazard level Red List of IUCN |
Remarks | image |
|---|---|---|---|---|---|
| Mississippi alligator |
Alligator mississippiensis ( Daudin , 1802) |
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 ( Least Concern - not at risk)
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monotypic Comes in the United States in the states of North Carolina , South Carolina , Georgia , Florida , Alabama , Mississippi , Louisiana , Arkansas , Oklahoma and Texas before |
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| China alligator |
Alligator sinensis Fauvel , 1879 |
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 ( Critically Endangered )
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monotypic Comes in China at the mouth reaches of the Yangtze River and its tributaries in the provinces of Anhui , Zhejiang and Jiangsu before |
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The genus alligator originated around 38 to 26 million years ago in the Oligocene in North America. A representative from this period was alligator prenasalis . In the Miocene lived Alligator mcgrewi , Alligator olseni and also the first mississippiensis Alligator . From the Pliocene was Alligator mefferdi described. Alligator sinensis appears in the Pleistocene .
- † Alligator prenasalis ( Loomis , 1904)
- † Alligator mcgrewi Schmidt , 1941
- † Alligator luicus Li & Wang , 1987
- † Alligator Olseni White , 1942
- † Alligator mefferdi Mook , 1923
- † Alligator thomsoni Mook , 1946 (possibly identical to Alligator mississippiensis )
literature
- Steve Grenard: Handbook of alligators and crocodiles . Krieger Publishing Company, Malabar, Florida 1991, ISBN 0-89464-435-1 , pp. 63-65 .
- Christopher A. Brochu: Crocodylian Snouts in Space and Time: Phylogenetic Approaches Toward Adaptive Radiation. American Zoologist volume 41 Issue 3 . Oxford University Press, 2001, ISSN 0003-1569 , pp. 564-585 .
Web links
Individual evidence
- ↑ Alligator mississippiensis in the IUCN Red List of Threatened Species 2016.3. Listed by: Crocodile Specialist Group, 1996. Retrieved February 8, 2017.
- ↑ Alligator sinensis in the IUCN Red List of Threatened Species 2016.3. Listed by: Crocodile Specialist Group, 1996. Retrieved February 8, 2017.