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 Alphaproteobacteria Garrity et al. 2006
                   Order Caulobacteralesᵀ Henrici and Johnson 1935 (Approved Lists 1980)
                     Family Caulobacteraceaeᵀ Henrici and Johnson 1935 (Approved Lists 1980)
                       1 Genus Aquidulcibacter Cai et al. 2018
                       2 Genus Asticcacaulis Poindexter 1964 (Approved Lists 1980)
                       3 Genus Brevundimonas Segers et al. 1994
                       4 Genus Caulobacterᵀ Henrici and Johnson 1935 (Approved Lists 1980) [polyphyletic]
                       5 Genus Peiella Wu et al. 2024
                       6 Genus Phenylobacterium Lingens et al. 1985
                       7 Genus Pseudaquidulcibacter Liu et al. 2022
                       8 Genus Terricaulis Vieira et al. 2020
                       9 Genus "Candidatus Acaudatibacter" Hallgren et al. 2025 nom. pro-inval.