High Quality Content by WIKIPEDIA articles! Pampatheridae ("Pampas beasts") is an ancient family, now extinct, of large armadillo-like plantigrade armored xenarthrans. They are related to Glyptodontidae, an extinct family of much larger and more heavily armored xenarthrans, as well as to smaller extant armadillos (Dasypodidae). However, Pampatheriidae has existed as a separate lineage at least since the middle Eocene Mustersan age, 45-48 million years ago. Pampatheres evolved in South America during its long period of Cenozoic isolation. Although widespread, they were less diverse and abundant than the armadillos.Holmesina spread to North America after the formation of the Isthmus of Panama as part of the Great American Interchange. They finally disappeared on both continents in the end-Pleistocene extinctions, about 12 000 years ago.