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 "Deltaproteobacteria" Kuever et al., 2006 [polyphyletic]
               Class Deltaproteobacteriaᵀ Kuever et al. 2006
                 Order Desulfurellales Kuever et al. 2006 [monotypic]
                   Family Desulfurellaceaeᵀ Kuever et al. 2006
                     Genus Hippea Miroshnichenko et al. 1999
                       1 Hippea maritimaᵀ Miroshnichenko et al. 1999
                       2 Hippea alviniae Flores et al. 2012
                       3 Hippea jasoniae Flores et al. 2012