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
                     Family Sulfurimonadaceae Waite et al. 2020
                       1 Genus Sulfuricurvum Kodama and Watanabe 2004 [monotypic]
                       2 Genus Sulfurimonas Inagaki et al. 2003
                       3 Genus Thiovulum Hinze 1913 (Approved Lists 1980) [monotypic]
                       4 Genus "Hydrocurvibacter" Cui et al. 2025 nom. inval.
                       5 Genus "Sulfonitrofixus" Cui et al. 2025 nom. inval.
                       6 Genus "Thiomicrolovo" Cui et al. 2025 nom. inval.