procaryotes
   Domain Bacteria Woese et al. 1990 stat. inval. see Domain Bacteria Woese et al. 2024
     Phylum Proteobacteria Garrity and Holt 2001 nom. nud. see Phylum Proteobacteria Garrity et al. 2005 stat. inval.
       Class "Alphaproteobacteria" "Garrity and Holt 2001" nom. nud. see Class Alphaproteobacteria Garrity et al. 2006
         Order Rickettsiales Gieszczykiewicz 1939 (Approved Lists 1980)
           Family "Holosporaceae" "Garrity and Holt 2001" nom. nud. see Family Holosporaceae Görtz and Schmidt 2006
             Genus Polynucleobacter Heckmann and Schmidt 1987