Josephoartigasia monesi

fossil rodent

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July 17, 2026

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Josephoartigasia monesi was the largest rodent known to have ever lived. This extinct species inhabited South America during the Pliocene and Pleistocene epochs, approximately two to four million years ago. Estimates suggest it could reach lengths of about 3 meters (10 feet) and weigh nearly 1,000 kg (2,200 pounds). This makes it significantly larger than the capybara, the largest living rodent, which typically weighs between 35 and 66 kg (77 to 146 pounds). The pacarana (Dinomys branickii) is the only living member of the family Dinomyidae, which includes extinct giant rodents like Josephoartigasia monesi.123

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General features
The largest rodent ever recorded, Josephoartigasia monesi, lived some two to four million years ago, during the Pleistocene and Pliocene epochs; by some estimates it grew to a length of about 3 metres (10 feet) and weighed nearly 1,000 kg.
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The largest rodent ever recorded, Josephoartigasia monesi, lived some two to four million years ago, during the Pleistocene and Pliocene epochs; by some estimates it grew to a length of about 3 metres (10 feet) and weighed nearly 1,000 kg.
Read More