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
           Subphylum Plicostoma Patterson, 1988 ex T. Cavalier-Smith, 1998 see Phylum Euglenozoa Cavalier-Smith, 1981
             Class Euglenoidea Bütschli, 1884
               1 Order Petalomonadida Cavalier-Smith, 1993
               2 Order Peranemida Bütschli, 1884
               3 Order Rhabdomonadida Leedale, 1967
               4 Order Euglenida Bütschli, 1884 - euglenids