Stegomastodon platensis (Proboscidea, Gomphotheriidae) en el Pleistoceno de Santiago del Estero, Argentina

mammal fossil remains from santiago del estero province (argentina) are very poorly known. in this paper, best preserved specimens of gomphotheriidae (mammalia, proboscidea) are presented. they come from quaternary beds outcropping along the río dulce, near of the city of santiago del estero. the comparative study with other south american gomphotheres remains, mainly from argentina and brazil, allow their identification as stegomastodon platensis, being among the largest forms of this species. previous studies referred this locality to the late pleistocene. enamel tooth sample was dated to 19.900 ± 120 bp by ams 14c, supporting that age for this fauna. carbon and oxygen isotopic composition of the tooth enamel has been analyzed to get new data on the paleodiet and habitat preference of south american gomphotheres. carbon isotopic values indicate an adaptation to an exclusively c4 diet. the oxygen isotopic analysis indicates cooler climatic conditions than present.