Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Clade neomura Cavalier-Smith, 1987
             Domain Archaea Woese et al. 2024 [paraphyletic]
               Kingdom Methanobacteriati (Garrity and Holt 2023) Oren and Göker 2024
                 Phylum Methanobacteriotaᵀ Garrity and Holt 2023
                   Class "Methanomicrobia" Garrity et al. 2005 nom. inval.
                     Order Methanomicrobialesᵀ Balch and Wolfe 1981
                       Family Methanomicrobiaceaeᵀ Balch and Wolfe 1981
                         1 Genus Methanochimaera Zhou et al. 2024
                         2 Genus Methanoculleus Maestrojuán et al. 1990
                         3 Genus Methanoeremita Zhou et al. 2024
                         4 Genus Methanofollis Zellner et al. 1999
                         5 Genus Methanogenium Romesser et al. 1981
                         6 Genus Methanolacinia Zellner et al. 1990
                         7 Genus Methanomicrobiumᵀ Balch and Wolfe 1981 [monotypic]
                         8 Genus Methanoplanus Wildgruber et al. 1984
                         9 Genus Methanovulcanius Chien et al. 2023