Swamp rats
| Swamp rats | ||||||||||||
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Real swamp rat ( Holochilus brasiliensis ) |
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| Systematics | ||||||||||||
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| Scientific name | ||||||||||||
| Holochilus | ||||||||||||
| Brandt , 1835 |
The swamp rats ( Holochilus ) are a genus of New World mice that live as shore inhabitants in swamp areas in South America . They were mostly placed near the cotton rats ( Sigmodon ), but new molecular genetic analyzes suggest that they are more closely related to the rice rats ( Oryzomys ).
The length of the body of the head is between 13 and 22 centimeters, depending on the species, plus a tail that is about the same length. The fur is beige or brown on the top and white on the underside. The body is typical of a rat shape . The swamp rats differ from the externally very similar cotton rats mainly in the webbing between the toes and also in the softer fur.
Swamp rats are common in tropical and subtropical South America east of the Andes . Here they live on river banks, in swamps and in reed forests . A nest is built from reeds and leaves that hangs up to 3 meters above the water in reeds or bushes. A swamp rat nest has a diameter of up to 40 centimeters. In the event of danger, the residents jump directly into the water below and flee by swimming.
Swamp rats are extremely common in some regions. The Pantanal in southwestern Brazil is one of the areas that offer them perfect conditions . Here you can count up to ten nests in some bushes. In a few years there will also be sudden population explosions, the causes of which are not fully understood. This rapid increase in populations goes hand in hand with the incursion of swamp rats into neighboring settlements. But they end just as suddenly due to an equally puzzling mass death of animals.
The following types are known:
- The real swamp rat ( Holochilus brasiliensis ) lives in Brazil, Paraguay , Uruguay and northern Argentina .
- Holochilus sciureus inhabits Brazil, Bolivia , eastern Peru , Venezuela , Guyana , Suriname, and French Guiana .
- The Chaco swamp rat ( Holochilus chacarius ) is native to Paraguay and northern Argentina.
A fourth species, Holochilus magnus , is usually placed in its own genus Lundomys today.
literature
- Ronald M. Nowak: Walker's Mammals of the World. 2 volumes. 6th edition. Johns Hopkins University Press, Baltimore MD et al. 1999, ISBN 0-8018-5789-9 .
