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 Methanococci Boone 2002 [monotypic]
                   Order Methanococcalesᵀ Balch and Wolfe 1981
                     Family Methanococcaceaeᵀ Balch and Wolfe 1981
                       Genus Methanococcusᵀ Kluyver and van Niel 1936 (Approved Lists 1980)
                         Methanococcus vannielii Stadtman and Barker 1951 (Approved Lists 1980)