Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Domain Bacteria Woese et al. 2024
             Kingdom Pseudomonadati (Gibbons and Murray 1978) Oren and Göker 2024
               Phylum Spirochaetota Garrity and Holt 2021
                 Class Spirochaetiaᵀ Paster 2020
                   Order Brachyspirales Gupta et al. 2014 [monotypic]
                     Family Brachyspiraceaeᵀ Paster 2012
                       Genus Brachyspiraᵀ Hovind-Hougen et al. 1983
                         1 Brachyspira aalborgiᵀ Hovind-Hougen et al. 1983
                         2.1 Brachyspira alvinipulli Stanton et al. 1998
                         2.2 Brachyspira hyodysenteriae (Harris et al. 1972) Ochiai et al. 1998
                         2.3 Brachyspira innocens (Kinyon and Harris 1979) Ochiai et al. 1998
                         2.4 Brachyspira intermedia (Stanton et al. 1997) Hampson and La 2006
                         2.5 Brachyspira murdochii (Stanton et al. 1997) Hampson and La 2006
                         2.6 Brachyspira pilosicoli (Trott et al. 1996) Ochiai et al. 1998