prokaryotes - bacteria see Domain Bacteria Woese et al. 1990
   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 Rhodospirillales Pfennig and Trüper 1971 (Approved Lists 1980)
           Family Rhodospirillaceae Pfennig and Trüper 1971 (Approved Lists 1980)
             01 Genus Aestuariispira Park et al. 2014
             02 Genus Azospirillum Tarrand et al. 1979 (Approved Lists 1980)
             03 Genus Caenispirillum Yoon et al. 2007
             04 Genus Conglomeromonas Skerman et al. 1983 see Genus Azospirillum Tarrand et al. 1979 (Approved Lists 1980)
             05 Genus Constrictibacter Yamada et al. 2011
             06 Genus Defluviicoccus corrig. Maszenan et al. 2005
             07 Genus Desertibacter Liu et al. 2011
             08 Genus Dongia Liu et al. 2010
             09 Genus Elstera Rahalkar et al. 2012
             10 Genus Ferrovibrio Sorokina et al. 2013
             11 Genus Fodinicurvata Wang et al. 2009
             12 Genus Inquilinus Coenye et al. 2002
             13 Genus Insolitispirillum Yoon et al. 2007
             14 Genus Lacibacterium Sheu et al. 2013
             15 Genus Limibacillus Kim et al. 2015
             16 Genus Limimonas Amoozegar et al. 2013
             17 Genus Magnetospira Williams et al. 2012
             18 Genus Magnetospirillum Schleifer et al. 1992
             19 Genus Magnetovibrio Bazylinski et al. 2013
             20 Genus Marispirillum Lai et al. 2009
             21 Genus Nisaea Urios et al. 2008
             22 Genus Nitrospirillum Lin et al. 2015
             23 Genus Novispirillum Yoon et al. 2007
             24 Genus Oceanibaculum Lai et al. 2009
             25 Genus Pelagibius Choi et al. 2009
             26 Genus Phaeospirillum Imhoff et al. 1998
             27 Genus Phaeovibrio Lakshmi et al. 2011
             28 Genus Rhodocista Kawasaki et al. 1994
             29 Genus Rhodospira Pfennig et al. 1998
             30 Genus Rhodospirillum Molisch 1907 (Approved Lists 1980)
             31 Genus Rhodovibrio Imhoff et al. 1998
             32 Genus Roseospira Imhoff et al. 1998
             33 Genus Skermanella Sly and Stackebrandt 1999
             34 Genus Taonella Xi et al. 2013
             35 Genus Telmatospirillum Sizova et al. 2007
             36 Genus Thalassobaculum Zhang et al. 2008
             37 Genus Thalassospira López-López et al. 2002
             38 Genus Tistlia Díaz-Cárdenas et al. 2010
             39 Genus Tistrella Shi et al. 2003