Caviidae
Caviidae, the cavy family, is composed of rodents native to South America and includes the domestic guinea pig, wild cavies, and the largest living rodent, the capybara. They are found across South America in open areas from moist savanna to thorn forests or scrub desert. This family of rodents has fewer members than most other rodent families, with 19 species in 6 genera in 3 subfamilies.
Telicomys
With a length of more than in "T. gigantissimus", it contains two or three of the largest rodents that ever lived, along with "Phoberomys", "Josephoartigasia", and the giant beaver. It is part of the same South American radiation of rodents as both "Phoberomys" and the modern capybara, which is the largest living rodent, reaching lengths of up to . The closest living relative to "Telicomys" is the pacarana.