† L. armatus Gervais 1855, type Lestodon is an extinct genus of giant ground sloth native to South America during the Pleistocene epoch.

It is the titular genus of the tribe Lestodontini, which often aside from Lestodon, includes Thinobadistes, Lestobradys and Bolivartherium,[8] though this grouping as a whole is not always recovered as monophyletic.

[10] Volumetric estimates suggests a body mass of around 4,100 kilograms (9,000 lb),[11] making it one of the largest known ground sloths, alongside the megatheres Megatherium and Eremotherium.

[15] The molariform teeth are largely similar to each other, aside from the last lower molar "which has two rounded lobes separated by a narrow constriction giving it a figure-8 shape".

[16] The olecranon process of the ulna of Lestodom armatus is slightly short compared to body size, though large in absolute terms.

[19] Lestodon armatus is primarily known from the Pampas and the Chaco-Paraná Basin, including what is now southern Brazil, Paraguay, Uruguay, and northern Argentina.

[22] Lestodon is thought to have been a bulk feeder that indiscriminately consumed large amounts of vegetation, using its probably square, white rhinoceros-like lips to pluck grass and other low lying plants in combination with the tongue.

[18] A bonebed of 13 Lestodon armatus individuals of different ages found together at the Playa del Barco site in Argentina suggests that the species engaged in gregarious behaviour, living at least some of the time in social groups.

[25] It has been suggested based on the likely sexual dimorphism of the lower tusk-like caniniforms, that Lestodon armatus had a polygynous mating system, with males possibly engaging in combat with each other over females.

[15] Researchers working at the Arroyo del Vizcaíno site near Sauce, Uruguay suggested that Lestodon was hunted by humans about 30,000 years ago.

[30] At the Paso Otero 5 site in the Pampas of northeast Argentina, Fishtail points are associated with burned bones of Lestodon and other extinct megafauna.