Mammaliaformes Rowe 1988 [nom. cl. nov.]
   [crown] Class Mammalia Linnaeus, 1758 - mammals
     1 Subclass Prototheria Gill, 1872 - monotremes see Order Monotremata Bonaparte, 1837
     2 Subclass Theriiformes (Rowe, 1988) M.C. McKenna & S.K. Bell, 1997 see Division Theriiformes