Dinomyidae

Dinomyidae is a family of South American hystricognath rodents that was once far more diverse but today survives as a single living species, the pacarana, Dinomys branickii, a rodent considerably smaller than the capybara. Its fossil relatives included some of the largest rodents known, such as the bison-sized Josephoartigasia monesi and the somewhat smaller Josephoartigasia magna, herbivorous forms that filled grazing-mammal niches before disappearing after the land connection between South and North America formed. The family fossil record spans from the Early Miocene to the present.