[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   Domain Bacteria Woese et al. 1990
     Phylum "Proteobacteria" Garrity et al. 2005 see Superphylum Proteobacteria Craig et al. 2010
       Class Alphaproteobacteria Garrity et al. 2006
         Order Rhizobiales Kuykendall 2006
           01 Family Rhizobiaceae Conn 1938 (Approved Lists 1980)
           02 Family "Aurantimonadaceae" Garrity et al., 2003
           03 Family Bartonellaceae Gieszczykiewicz 1939 (Approved Lists 1980)
           04 Family Brucellaceae Breed et al. 1957 (Approved Lists 1980)
           05 Family Phyllobacteriaceae Mergaert and Swings 2006
           06 Family Methylocystaceae Bowman 2006
           07 Family Beijerinckiaceae Garrity et al. 2006
           08 Family Bradyrhizobiaceae Garrity et al. 2006
           09 Family Hyphomicrobiaceae Babudieri 1950 (Approved Lists 1980)
           10 Family Methylobacteriaceae Garrity et al. 2006
           11 Family Rhodobiaceae Garrity et al. 2006