[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain "Archaea" Woese et al. 1990 stat. inval. see Domain Archaea Woese et al. 2024
     Phylum "Euryarchaeota" Garrity and Holt 2002 stat. inval. see Kingdom Methanobacteriati (Garrity and Holt 2023) Oren and Göker 2024
       Class "Methanomicrobia" Garrity et al. 2005 nom. inval.
         Order Methanomicrobiales Balch and Wolfe 1981
           Family Methanospirillaceae Boone et al. 2002
             Genus Methanospirillum Ferry et al. 1974 (Approved Lists 1980)
               Methanospirillum hungatei corrig. Ferry et al. 1974 (Approved Lists 1980)