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 Chromatiales Imhoff 2005
                     Family Chromatiaceae Bavendamm 1924 (Approved Lists 1980)
                       Genus Nitrosococcus Winogradsky 1892 (Approved Lists 1980)
                         Nitrosococcus oceani corrig. (Watson 1965) Watson 1971 (Approved Lists 1980)