Giant hutia
The giant hutias are an extinct group of large rodents known from fossil and subfossil material in the West Indies. One species, "Amblyrhiza inundata", is estimated to have weighed between , big specimens being as large as an American black bear. This is twice as large as the capybara, the largest rodent living today, but still much smaller than "Josephoartigasia monesi", the largest rodent known. These animals were probably used as a food source by aboriginal humans. All giant hutias are in a single family, Heptaxodontidae, which contains no living species; this grouping seems to be paraphyletic and artificial, however.
Mara (mammal)
The maras ("Dolichotis") are a genus of the cavy family of rodents. They are the sole extant representatives of the subfamily Dolichotinae. These large relatives of guinea pigs are common in the Patagonian steppes of Argentina, but also live in Paraguay and elsewhere in South America. Maras are the fourth-largest rodent in the world, after capybaras, beavers, and porcupines, reaching about in height.