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 Pseudomonadotaᵀ Garrity et al. 2021
                 Class Alphaproteobacteria Garrity et al. 2006
                   Order Rickettsiales Gieszczykiewicz 1939 (Approved Lists 1980)
                     Family Rickettsiaceae Pinkerton 1936 (Approved Lists 1980)
                       01 Genus Occidentia Mediannikov et al. 2017
                       02 Genus Orientia Tamura et al. 1995 [monotypic]
                       03 Genus Rickettsiaᵀ da Rocha-Lima 1916 (Approved Lists 1980) nom. cons.
                       04 Genus "Candidatus Cryptoprodota" corrig. Ferrantini et al. 2020
                       05 Genus "Candidatus Gigantorickettsia" corrig. Vannini et al. 2020
                       06 Genus "Candidatus Hemipteriphilus" Bing et al. 2020
                       07 Genus "Candidatus Megaera" corrig. Schrallhammer et al. 2020
                       08 Genus "Candidatus Phycorickettsia" Yurchenko et al. 2020
                       09 Genus "Candidatus Sarmatiella" Castelli et al. 2022 nom. pro-illeg.
                       10 Genus "Candidatus Spectririckettsia" Castelli et al. 2021
                       11 Genus "Candidatus Trichorickettsia" Vannini et al. 2020
                       12 Genus "Candidatus Xenohaliotis" Friedman et al. 2000 [monotypic]