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 Thermoproteiᵀ Reysenbach 2002
                     Order Thermoprotealesᵀ Zillig and Stetter 1982
                       Family Thermofilaceae Burggraf et al. 1997
                         Genus Infirmifilum Zayulina et al. 2024