[organisms] see Clade Biota Wagner 2004 [Wiemann, de Queiroz, Rowe, Planavsky, Anderson, Gogarten, Turner & Gauthier 2020]
   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 Rickettsiales Gieszczykiewicz 1939 (Approved Lists 1980)
           Family Rickettsiaceae Pinkerton 1936 (Approved Lists 1980)
             Genus Rickettsia da Rocha-Lima 1916 (Approved Lists 1980)
               Rickettsia rickettsii (Wolbach 1919) Brumpt 1922 (Approved Lists 1980)