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 Fibrobacterota Garrity and Holt 2021
                 1 Class Chitinispirillia Sorokin et al. 2016 [monotypic]
                 2 Class Chitinivibrionia Sorokin et al. 2014 [monotypic]
                 3 Class Fibrobacteriaᵀ Spain et al. 2012