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 "Candidatus Hydrothermarchaeota" Jungbluth et al. 2023 [monotypic]
                   1 Genus "Candidatus Pyrohabitans" Adam et al. 2022 nom. pro-inval.
                   2 Class "Candidatus Hydrothermarchaeia"ᵀ Chuvochina et al. 2019 nom. pro-inval. [monotypic]