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
             1 Genus Holospora (ex Hafkine 1890) Preer and Preer 1982 nom. illeg. see Genus Holospora (ex Hafkine 1890) Gromov and Ossipov 1981
             2 Genus Caedibacter (ex Preer et al. 1974) Preer and Preer 1982
             3 Genus Lyticum (ex Preer et al. 1974) Preer and Preer 1982
             4 Genus Polynucleobacter Heckmann and Schmidt 1987
             5 Genus Pseudocaedibacter Quackenbush 1982
             6 Genus Symbiotes Philip 1956 (Approved Lists 1980)
             7 Genus Tectibacter (ex Preer et al. 1974) Preer and Preer 1982