Perutherium altiplanense, un Notongulé du Cretacé Supérieur du Pérou

Larry G. Marshall, Christian de Muizon and Bernard Sigé

Perutherium altiplanerise THALER, 1967 from the Late Cretaceous of Peru has long been recognized as South America's oldest known placental mammal. Since its description Perutherium has been generally regarded as having condylarth affinity Based on our identification  of a unique notoungulate synapomorphy we recognize Perutherium as the oldest and the most generalized known member of that order. This new determination and the large taxonomic diversity (five families) of notoungulates in rocks of Paleocene age in Argentina and Brazil, favor a South American origin for this group. The occurrence of notoungulates in rocks of Late Paleocene age in Asia and North America is explained by dispersal of a notoungulate stock from South America to North America and from there to Asia.