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Neofiber alleni

Round-tailed Muskrat

Order: Rodentia
Family: Cricetidae

Image of Neofiber alleni
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Conservation Status: Least Concern.

Round-tailed Muskrats inhabit freshwater marshes in peninsular Florida and south-central and southeastern Georgia. As many as 48 muskrats per hectare have been recorded in the Everglades. They seem to prefer water about 30-45 cm (12-18 inches) deep. They construct roundish houses about 18 to 60 cm (7 to 24 inches) in diameter at the surface of the water, with two underwater entrances that are called plunge holes. The Muskrats are nocturnal and are most active shortly after dark. The stems of aquatic grasses form the bulk of their diet. When water levels are low, they can burrow into wet mud and survive for a significant period of time. Bobcats and some snakes and birds prey on these rodents.

Also known as:
Florida Water Rat, Water Rat

Sexual Dimorphism:

Average: 345 mm
Range: 285-381 mm

Average: 328 g
Range: 190-350 g


True, F.W., 1884.  A muskrat with a round tail.  Science, 4:34.


Mammal Species of the World

Mammalian Species, American Society of Mammalogists' species account

Distribution of Neofiber alleni