Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Clade neomura Cavalier-Smith, 1987
             Domain Archaea Woese et al. 1990 [paraphyletic]
               Phylum Euryarchaeota Garrity and Holt 2001
                 Class "Methanomicrobia"
                   Order Methanosarcinales Boone et al. 2002
                     Family Methanosaetaceae Boone et al. 2002 nom. illeg. [monotypic]
                       Genus Methanothrix Huser et al. 1983
                         Methanothrix soehngeniiᵀ Huser et al. 1983