Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Domain Bacteria Woese et al. 1990 [paraphyletic?]
             Superphylum "Proteobacteria" Craig et al. 2010
               Phylum "Betaproteobacteria" Garrity et al., 2006 [monotypic]
                 Class Betaproteobacteriaᵀ Garrity et al. 2006
                   Order Burkholderiales Garrity et al. 2006
                     Family Burkholderiaceaeᵀ Garrity et al. 2006
                       Genus Polynucleobacter Heckmann and Schmidt 1987
                         Polynucleobacter necessariusᵀ Heckmann and Schmidt 1987
                           Polynucleobacter necessarius subsp. asymbioticus Hahn et al. 2009