Kingdom Bacteria Cavalier-Smith 2002 - bacteria see Domain Bacteria Woese et al. 1990
   Subkingdom Negibacteria Cavalier-Smith 2002 - negibacteria see Domain Bacteria Woese et al. 1990
     Infrakingdom Glycobacteria Cavalier-Smith 2002 see Domain Bacteria Woese et al. 1990
       Division Spirochaetae Cavalier-Smith 2002
         Class Spirochaetes Cavalier-Smith 2002
           1 Genus Treponema Schaudinn 1905 (Approved Lists 1980)
           2 Genus Borellia orth. inval. see Genus Borrelia Swellengrebel 1907 (Approved Lists 1980)
           3 Genus Leptospira Noguchi 1917 (Approved Lists 1980)
           4 Genus Leptonema Hovind-Hougen 1983
           5 Order Spirochaetales Buchanan 1917 (Approved Lists 1980)