Glyptodon clavipes

Glyptodon clavipes bore a rigid, dome-shaped bony carapace that could reach up to about 1.5 meters (roughly 5 feet) in length, making it comparable in size to a Volkswagen Beetle. It was a member of the glyptodonts, extinct relatives of modern armadillos. Including its head and tail, the animal could weigh well over a ton.

Glyptodon and its close relatives went extinct during the Late Pleistocene, roughly 10,000 to 11,000 years ago, during the Quaternary extinction event that also claimed many other large South American mammals. Climate change and human hunting are both considered contributing factors. Fossil evidence suggests coexistence with early human populations in South America, who may have used glyptodont shells as shelters.

Yes—glyptodons belong to the cingulate clade within Xenarthra, the same broader group that includes modern armadillos, sloths, and anteaters. Modern armadillos such as Dasypus are among their closest living relatives. The main difference is that glyptodons had a single fused, rigid carapace, whereas most modern armadillos have segmented, flexible bands of armor that allow them to curl up.

Glyptodon fossils are found primarily in South America, particularly in Argentina, Uruguay, and Brazil, in Pleistocene-age deposits. During the Great American Biotic Interchange—triggered by the formation of the Isthmus of Panama roughly 3 million years ago—glyptodonts dispersed northward into Central and North America. Fossils of related glyptodont genera have been found as far north as the southern United States.