Phylum Chordata Bateson, 1885 - chordates
   Class Aves Linnaeus, 1758 - birds see Subclass Aves Linnaeus, 1758
     Subclass Neornithes Gadow, 1893 see Clade Neornithes Gadow, 1893
       Superorder Neognathae Pycraft, 1900 see Cohort Neognathae Pycraft, 1900
         Order Charadriiformes Huxley, 1867 - shorebirds, gulls, auks
           Suborder Lari Sharpe, 1891 - gulls and allies
             Family Laridae Vigors, 1825 - gulls, terns and skimmers
               Subfamily Larinae Vigors, 1825 - gulls
                 Genus Pagophila Kaup, 1829
                   Pagophila eburnea (Phipps, 1774) - ivory gull