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 Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
           Order Picae Linnaeus, 1758 see Parvclass Picae (C. Linnaeus, 1758)
             Genus Upupa Linnaeus, 1758
               1 Upupa epops Linnaeus, 1758 - Eurasian hoopoe
               2 Upupa paradisea Linnaeus, 1758
               3 Upupa eremita Linnaeus, 1758 see Geronticus eremita (Linnaeus, 1758)
               4 Upupa pyrrhocorax Linnaeus, 1758 see Pyrrhocorax pyrrhocorax (C. Linnaeus, 1758)