eukaryotes see Domain Eukaryota Chatton, 1925
   Kingdom Protozoa Goldfuss, 1818 [paraphyletic] - protozoa
     Subkingdom Natozoa Cavalier-Smith, 2021 [paraphyletic]
       Infrakingdom Archezoa Cavalier-Smith, 1983 [monotypic] see Phylum Metamonada Grassé, 1952
         Phylum Metamonada Grassé, 1952
           Subphylum Anaeromonada Cavalier-Smith, 1997 [monotypic]
             Class Anaeromonadea Cavalier-Smith, 1997
               Order Oxymonadida Grassé, 1952 - oxymonads
                 Genus Streblomastix Kofoid & Swezy, 1920