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?]
             Phylum Thermotogae Reysenbach 2001 [monotypic]
               Class Thermotogaeᵀ Reysenbach 2002 [monotypic]
                 Order Petrotogales Bhandari and Gupta 2014 [monotypic]
                   Family Petrotogaceaeᵀ Bhandari and Gupta 2014
                     Genus Petrotogaᵀ Davey et al. 1993
                       1 Petrotoga halophila Miranda-Tello et al. 2007
                       2 Petrotoga mexicana Miranda-Tello et al. 2004
                       3 Petrotoga miothermaᵀ Davey et al. 1993
                       4 Petrotoga mobilis Lien et al. 1998
                       5 Petrotoga olearia L'Haridon et al. 2002
                       6 Petrotoga sibirica L'Haridon et al. 2002