Late Tertiary Rodents from the Catamarca Province, Argentina : The Field Museum Collections

The rodents collected in the 1920\u27s by the Marshall Field Expedition for the Field Museum of Natural History, Chicago, are systematically reviewed and placed within the stratigraphic framework established at the time of collection. One new genus (Proeuryzygomys) and three new species (Abracoma intermedias, Proeuryzygomys diminutiva, and Cayiodon (Lelongia) catamarcensis) are proposed. Two distinct faunas are recognized corresponding to the Huayquerian and Montehermosan Land Mammal Ages respectively. Several computer programs were developed to aid in character analysis