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  Rodentia · Cricetidae · Nyctomys sumichrasti
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Nyctomys sumichrasti

Sumichrast’s Vesper Rat

Order: Rodentia
Family: Cricetidae


Conservation Status: Least Concern.

Sumichrast’s Vesper Rats are medium-sized, stocky rats. They spend most of their lives in trees, and can hang by the curved claws on their hind feet to reach fruit. These rats sit on their haunches like squirrels to eat, dropping the seeds and skin. They nest on branches or in tree cavities. In captivity, males and females both built round nests. Males usually stayed out of the nest for about a week after a litter was born. Newborns weighed about 4.7 g, or less than two U.S. penny coins. By two weeks of age, they had glossy hair and could climb on branches, but quickly got chilly out of the nest. Soon after, they stopped nursing; by about 75 days, they were sexually mature and ready to reproduce. One female had three litters in seven months, with an average litter size of two.

Range: Head and Body: 107-130 mm; Tail: 85-155 mm

Range: 39-61 g


Saussure, M.H., 1860. Revue et Magasin de Zoologie Pure et Appliquée, Paris, ser. 2, 12:107.


Mammal Species of the World

Distribution of Nyctomys sumichrasti