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]
           Clade neomura Cavalier-Smith, 1987
             Domain Eukaryota Chatton, 1925 - eukaryotes
               Clade discaria Cavalier-Smith, 2021
                 Clade dorsates Cavalier-Smith, 2021
                   Clade podiates Cavalier-Smith, 2012
                     Clade Amorphea Adl et al. 2012 [Simpson, Medina & Adl 2020]
                       Clade Obazoa Brown, Sharpe, Silberman, Heiss, Lang, Simpson & Roger 2013
                         Clade Opisthokonta Cavalier-Smith 1987 [Simpson & Medina 2020] - animal-fungal clade
                           Superkingdom Holozoa Lang, O'Kelly, Nerad, Gray & Burger, 2002
                             Clade filozoa Shalchian-Tabrizi, Minge, Espelund, Orr, Ruden, Jakobsen & Cavalier-Smith, 2008
                               Kingdom Animalia Linnaeus, 1758 - animals
                                 Clade Planulozoa Wallberg, Thollesson, Farris & Jondelius 2004
                                   Subkingdom Bilateria Hatschek, 1888 - bilaterians
                                     Clade Nephrozoa Jondelius, Ruiz-Trillo, Baguñà & Riutort 2002
                                       Infrakingdom Deuterostomia Grobben, 1908
                                         Phylum Chordata Bateson, 1885 - chordates
                                           Subphylum Craniata auct.
                                             Infraphylum Vertebrata Lamarck, 1801 - vertebrates
                                               Superclass Petromyzontomorphi [monotypic]
                                                 Class Petromyzonti [monotypic]
                                                   Order Petromyzontiformes Berg, 1940 - lampreys
                                                     1 Family †"Hardistiellidae" Halstead, 1993, nom. nud. [monotypic]
                                                     2 Family †Mayomyzontidae Bardack & Zangerl, 1971 [monotypic]
                                                     3 Genus †Priscomyzon Gess et al., 2006 [monotypic]
                                                     4.1 Family Petromyzontidaeᵀ Bonaparte, 1831, sedis mutabilis - lampreys
                                                     4.2 Family Geotriidae Gill, 1893, sedis mutabilis [monotypic] - pouched lampreys
                                                     4.3 Family Mordaciidae Gill, 1893, sedis mutabilis [monotypic] - southern topeyed lampreys