organisms see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Kingdom Monera Haeckel 1866 see Domain Bacteria Woese et al. 1990
     Phylum "chemoautotrophic bacteria"
       Class "oxidizers of nitrogen compounds" see Phylum Proteobacteria Garrity and Holt 2001
         Order Nitrobacteriales see Phylum Proteobacteria Garrity and Holt 2001
           1 Genus Nitrobacter Winogradsky 1892 (Approved Lists 1980)
           2 Genus Nitrospina Watson and Waterbury 1971 (Approved Lists 1980)
           3 Genus Nitrocystis
           4 Genus Nitrococcus Watson and Waterbury 1971 (Approved Lists 1980)