 At the nearby Monte Hermoso beds the numerous rodents included species allied to the Brazilian tuco-tuco and the capybara.Owen decided that the fossils of polygonal plates of bony armour found at several locations were not from the Megatherium as Cuvier's description implied, but from a huge armadillo as Darwin had briefly thought.Owen found a description of an earlier unnamed specimen which he named "Glyptodon clavipes" in 1839.