eukaryotes see Domain Eukaryota Chatton, 1925
   Kingdom Protozoa Goldfuss, 1818 [paraphyletic] - protozoa
     Subkingdom Sarcomastigota Cavalier-Smith, 1983 [paraphyletic] see [unranked] dorsates Cavalier-Smith, 2021
       Phylum Choanozoa Cavalier-Smith, 1981 [paraphyletic]
         Subphylum Choanofila Cavalier-Smith, 2009 [paraphyletic] see Superkingdom Holozoa Lang, O'Kelly, Nerad, Gray & Burger, 2002
           1 Class Choanoflagellatea Cavalier-Smith, 1998
           2 Class Filasterea Cavalier-Smith, 2008 [monotypic]
           3 Class Corallochytrea Cavalier-Smith, 1995 [monotypic] see Order Corallochytrida Cavalier-Smith, 1995
           4 Class Ichthyosporea Cavalier-Smith, 1998