Procaryotic Genera
   Domain "Bacteria" Woese et al. 1990
     Phylum Proteobacteria Garrity and Holt 2001 see Phylum Proteobacteria Garrity et al. 2005
       Class "Alphaproteobacteria" Garrity and Holt 2001 nom. nud. see Class Alphaproteobacteria Garrity et al. 2006
         Order "Sphingomonadales" [monotypic] see Order Sphingomonadales Yabuuchi and Kosako 2006
           Family Sphingomonadaceae Kosako et al. 2000
             1 Genus Sphingomonasᵀ Yabuuchi et al. 1990
             2 Genus Blastomonas Sly and Cahill 1997
             3 Genus Erythrobacter Shiba and Simidu 1982
             4 Genus Erythromicrobium Yurkov et al. 1994
             5 Genus Erythromonas Yurkov et al. 1997 see Genus Blastomonas Sly and Cahill 1997
             6 Genus Porphyrobacter Fuerst et al. 1993
             7 Genus Rhizomonas van Bruggen et al. 1990
             8 Genus Sandaracinobacter Yurkov et al. 1997
             9 Genus Zymomonas Kluyver and van Niel 1936 (Approved Lists 1980)