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The origins of the distinct sloth lineages are not well documented. The Deseadan SALMA site of Salla-Luribay presents four Tardigrada and constitutes one of the two oldest sloth assemblages. The peculiar glypto-sloth Pseudoglyptodon sallaensis is found together with two orophodontoid taxa and a Megalonychidae. The study of the P. sallaensis remains confirms that is effectively a sloth with various glyptodontoid convergences easily explicable by a grazing way of life. The orophodontids exhibit a common dental pattern with Octodontotherium from Patagonia. Except for the presence of Pseudoglyptodon, the Salla-Luribay Xenarthra assemblage closely resembles the La Flecha site from Santa Cruz province, Argentina. The Megalonychidae are also recorded, which increases the paleogeographic distribution of this clade in the late Oligocene. The phylogenetic status of Pseudoglyptodon remains doubtful …