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]
           Domain Bacteria Woese et al. 2024
             Kingdom Pseudomonadati (Gibbons and Murray 1978) Oren and Göker 2024
               Phylum Pseudomonadotaᵀ Garrity et al. 2021
                 Class Epsilonproteobacteria Garrity et al. 2006
                   Family Nitratiruptoraceae Waite et al. 2020, incertae sedis
                     Genus Nitratiruptorᵀ Nakagawa et al. 2005 [monotypic]
                       1 Nitratiruptor tergarcusᵀ Nakagawa et al. 2005