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 Genus Ornithorhynchus Blumenbach, 1800 - duck-billed platypus