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 "Gammaproteobacteria" Garrity et al., 2005 [monotypic]
                 Class Gammaproteobacteriaᵀ Garrity et al. 2005
                   Order Acidiferrobacterales Kojima et al. 2015 [monotypic]
                     Family Acidiferrobacteraceaeᵀ Kojima et al. 2015
                       1 Genus Acidiferrobacterᵀ Hallberg et al. 2011 [monotypic]
                       2 Genus Sulfuricaulis Kojima et al. 2016
                       3 Genus Sulfurifustis Kojima et al. 2015