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 "Rhizobiales" see Order Rhizobiales Kuykendall 2006
           01 Family Rhizobiaceae Conn 1938 (Approved Lists 1980)
           02 Family Bartonellaceae Gieszczykiewicz 1939 (Approved Lists 1980) [monotypic]
           03 Family Brucellaceae Breed et al. 1957 (Approved Lists 1980)
           04 Family "Phyllobacteriaceae" see Family Phyllobacteriaceae Mergaert and Swings 2006
           05 Family "Methylocystaceae" nom. inval. see Family Methylocystaceae Bowman 2006
           06 Family "Beijerinckiaceae" see Family Beijerinckiaceae Garrity et al. 2006
           07 Family "Bradyrhizobiaceae" Garrity et al. 2001 nom. ined. see Family Bradyrhizobiaceae Garrity et al. 2006
           08 Family Hyphomicrobiaceae Babudieri 1950 (Approved Lists 1980)
           09 Family "Methylobacteriaceae" nom. inval. see Family Methylobacteriaceae Garrity et al. 2006
           10 Family "Rhodobiaceae" [monotypic] see Family Rhodobiaceae Garrity et al. 2006