Imperium naturæ C. Linnaeus, 1758 - nature
   Mundus Plinius - physical world
     naturalia - natural bodies
       Regnum Animale C. Linnaeus, 1758 - animal kingdom see Kingdom Animalia Linnaeus, 1758
         Class Pisces Linnaeus, 1758 see Superclass Pisces Linnaeus, 1758
           Order Apodes Linnaeus, 1758 see Order Anguilliformes Rafinesque, 1810
             Genus Xiphias Linnaeus, 1758
               1 Xiphias gladius Linnaeus, 1758 - swordfish