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
                   Order Campylobacterales Garrity et al. 2006
                     1 Family Arcobacteraceae Waite et al. 2020
                     2 Family Campylobacteraceaeᵀ Vandamme and De Ley 1991
                     3 Family Helicobacteraceae Garrity et al. 2006
                     4 Family Hydrogenimonadaceae Waite et al. 2020 [monotypic]
                     5 Family Sulfurimonadaceae Waite et al. 2020
                     6 Family "Candidatus Thiobarbaceae" Assié et al. 2022 [monotypic]