Isotemnus primitivus Ameghino, 1897 Dataset GBIF Backbone Taxonomy Rank SPECIES Classification kingdom Animalia phylum Chordata class Mammalia family Isotemnidae genus Isotemnus species Isotemnus primitivus Name Synonyms Amphitemnus nucleatus Ameghino, 1904 Amphitemnus transitorius Ameghino, 1904 Dimerostephanos angustus (Ameghino, 1897) Eochalicotherium cretaceum Ameghino, 1901 Isotemnus conspiquus Ameghino, 1897 Trimerostephanos angustus (Ameghino, 1897) Homonyms Isotemnus primitivus Ameghino, 1897