Natura - nature
   actualia - actual entities
     Mundus Plinius - physical world
       naturalia - natural bodies
         [crown] Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
           Domain Bacteria Woese et al. 1990 [paraphyletic?]
             Superphylum Planctomycetes-Verrucomicrobia-Chlamydiae (PVC) Wagner and Horn 2006
               Phylum Chlamydiae Garrity and Holt 2012 [monotypic]
                 Class Chlamydiaeᵀ Cavalier-Smith 2002 [monotypic]
                   Order Chlamydialesᵀ Storz and Page 1971 (Approved Lists 1980)
                     Family Chlamydiaceaeᵀ Rake 1957 (Approved Lists 1980)
                       Genus Chlamydophila Everett et al. 1999
                         1.1.1.1.1 Chlamydophila abortus Everett et al. 1999
                         1.1.1.1.2 Chlamydophila psittaciᵀ (Lillie 1930) Everett et al. 1999
                         1.1.1.2 Chlamydophila caviae Everett et al. 1999
                         1.1.2 Chlamydophila felis Everett et al. 1999
                         1.2 Chlamydophila pecorum (Fukushi and Hirai 1992) Everett et al. 1999
                         2 Chlamydophila pneumoniae (Grayston et al. 1989) Everett et al. 1999