Mammalia Linnaeus 1758 [Rowe 1988], nom. cl. inval. see Class Mammalia Linnaeus, 1758
   Cetartiodactyla Montgelard, Catzeflis & Douzery 1997 see Order Cetartiodactyla Montgelard, Catzeflis & Douzery, 1997
     Whippomorpha Waddell, Okada & Hasegawa 1999 see Suborder Whippomorpha
       Cetacea Brisson 1762 see Suborder Cetacea Brisson, 1762
         Pelagiceti Uhen, 2008
           Neoceti Fordyce & de Muizon, 2001
             Mysticeti Cope, 1891 see Parvorder Mysticeti Cope, 1891
               Chaeomysticeti Mitchell, 1989
                 Balaenomorpha Geisler & Sanders, 2003
                   Plicogulae Geisler, McGowen, Young & Gatesy, 2011
                     Family †Cetotheriidae Brandt, 1872 [paraphyletic]
                       Subfamily †Herpetocetinae Steeman, 2007 [sister group to excluded taxa]
                         Genus †Nannocetus Kellogg, 1930