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 Thermoproteati Guy and Ettema 2024
                 Phylum Thermoproteotaᵀ Garrity and Holt 2021
                   Class Nitrososphaeria Stieglmeier et al. 2014
                     Order "Candidatus Caldarchaeales" Rinke et al. 2021 nom. pro-inval.
                       Family "Candidatus Caldarchaeaceae"ᵀ Rinke et al. 2021 nom. pro-inval.
                         1 Genus "Candidatus Caldarchaeum"ᵀ corrig. Nunoura et al. 2020
                         2 Genus "Pelearchaeum" Balbay et al. 2023 nom. inval.