Mammaliaformes Rowe 1988
[crown] Class Mammalia Linnaeus, 1758 - mammals
Subclass Prototheria Gill, 1872 - monotremes
Order Platypoda Gill, 1872 - platypuses
see Order Monotremata Bonaparte, 1837
Family Ornithorhynchidae Gray, 1825 - platypuses
1 Genus †Steropodon Archer, Flannery, Ritchie & Molnar, 1985
2 Genus †Monotrematum Pascual, Archer, Ortiz Jaureguizar, Prado, Godthelp & Hand, 1992
3 Genus †Obdurodon Woodburne & Tedford, 1975
4 Genus Ornithorhynchus Blumenbach, 1800 - duck-billed platypus