an extinct hoofed mammal of a large and varied group that lived in South America throughout the Tertiary period, finally dying out in the Pleistocene 南美有蹄动物
Order Notoungulata: many families 南方有蹄目: 多科
语源
late 20th cent.: from modern Latin Notoungulata, from Greek notos 'south' + Latin ungula 'nail'