Kingdom Protozoa Goldfuss, 1818 - protozoa
   Subkingdom Corticata Lankester, 1878 see Subkingdom Biciliata
     Infrakingdom Excavata T. Cavalier-Smith, 2002 see Supergroup Excavata Cavalier-Smith, 2002
       Superphylum Discicristata Cavalier-Smith, 1998
         Phylum Euglenozoa Cavalier-Smith, 1981
           Genus Petalomonas F. Stein, 1859
             Petalomonas cantuscygni J.P. Cann & N.C. Pennick, 1986