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] Pelecaniformes Sharpe, 1891
         ?Family Phaethontidae Brandt, 1831 [monotypic] - tropicbirds
           Genus Phaethon Linnaeus, 1758
             Phaethon rubricauda Boddaert, 1783 - red-tailed tropicbird
               1 Phaethon rubricauda rubricauda Boddaert, 1783
               2 Phaethon rubricauda westralis Mathews, 1912
               3 Phaethon rubricauda roseotinctus (Mathews, 1926)
               4 Phaethon rubricauda melanorhynchos Gmelin, 1789