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 Sulfolobales Stetter 1989 [monotypic]
                       Family Sulfolobaceaeᵀ Stetter 1989
                         01 Genus Acidianus Segerer et al. 1986
                         02 Genus Metallosphaera Huber et al. 1989
                         03 Genus Saccharolobus Sakai and Kurosawa 2018
                         04 Genus Stygiolobus Segerer et al. 1991 [monotypic]
                         05 Genus Sulfodiicoccus Sakai and Kurosawa 2017
                         06 Genus Sulfolobusᵀ Brock et al. 1972 (Approved Lists 1980)
                         07 Genus Sulfuracidifex Itoh et al. 2020
                         08 Genus Sulfurisphaera Kurosawa et al. 1998 [monotypic]
                         09 Genus Sulfurococcus Golovacheva et al. 1995
                         10 Genus "Caldariella" De Rosa et al. 1975 nom. inval.