Procaryotic Genera
   Domain "Bacteria" Woese et al. 1990 stat. inval. see Domain Bacteria Woese et al. 2024
     Phylum Spirochaetes Garrity and Holt 2001 nom. inval. [monotypic] see Phylum Spirochaetota Garrity and Holt 2021
       Class "Spirochaetes" "Garrity and Holt 2001" nom. nud. [monotypic] see Class Spirochaetes Cavalier-Smith 2002 nom. rej.
         Order Spirochaetales Buchanan 1917 (Approved Lists 1980)
           Family "Serpulinaceae" "Garrity and Holt 2001" nom. nud. see Family Brachyspiraceae nom. ined.
             1 Genus Serpulina Stanton 1992 see Genus Brachyspira Hovind-Hougen et al. 1983
             2 Genus Brachyspira Hovind-Hougen et al. 1983