Glyptotherium specimen. The fossils from South America are usually only osteoderms or caudal rings and are sometimes indeterminate on a species level, but are most likely from Glyptotherium cylindricum. Glyptotherium fossils have also been collected from Central America in Guatemala, Costa Rica, Honduras, El Salvador, and Panama. The fossils from Central America are usually isolated and fragmentary, with the majority being osteoderms or isolated molariforms. It is most likely that the first Glyptotherium populations started in Central America during the Great American Biotic Interchange in the Late Pliocene based on their paleobiogeography. Glyptotherium fossils from Central America are sometimes placed as an indeterminate species, but most are placed in Glyptotherium cylindricum or its synonyms. This referral is also based on the age of the fossils, as fossils from the Pliocene and early Pleistocene are from G. texanum while G. cylindricum is from the late Pleistocene. See also Glyptodon Boreostemma References Prehistoric cingulates Prehistoric placental genera Pliocene mammals of North America Pleistocene xenarthrans Pleistocene mammals of North America Zanclean first appearances Holocene extinctions Blancan Irvingtonian Lujanian Rancholabrean Pleistocene Brazil Holocene Brazil Fossils of Brazil Pleistocene Costa Rica Fossils of Costa Rica Pleistocene El Salvador Fossils of El Salvador Pleistocene Mexico Fossils of Mexico Pleistocene Panama Fossils of Panama Neogene United States Pleistocene United States Fossils of the United States Pleistocene mammals of South America Pleistocene Venezuela Fossils of Venezuela Fossil taxa described in 1903 Taxa named by Henry Fairfield Osborn