Neornithes Gadow, 1893 - living birds
   Neognathae Pycraft 1900 see Cohort Neognathae Pycraft, 1900
     Neoaves Sibley et al. 1988 see Subcohort Neoaves Sibley et al., 1988
       [Order] Charadriiformes Huxley, 1867 - shorebirds, gulls, auks
         Family Alcidae Vigors, 1825 - auks
           Genus Aethia Merrem, 1788
             1 Aethia psittacula (Pallas, 1769) - parakeet auklet
             2 Aethia pusilla (Pallas, 1811) - least auklet
             3 Aethia pygmaea (Gmelin, 1789) - whiskered auklet
             4 Aethia cristatella (Pallas, 1769) - crested auklet