Vertebrata Cuvier, 1812 - vertebrates
Gnathostomata
Teleostomi
Tetrapoda Hatschek & Cori 1896 [Gauthier, Kluge & Rowe 1988]
Amniota Haeckel, 1866 [Gauthier, Kluge & Rowe 1988] - amniotes
Class Mammalia Linnaeus, 1758 - mammals
Subclass Theria Parker & Haswell, 1897
Theria of Metatherian-Eutherian grade
Infraclass Eutheria Gill, 1872
Order †Notoungulata Roth, 1903
Suborder †Toxodontia Owen, 1853
Family †Leontiniidae Ameghino, 1895