Class Mammalia Linnaeus, 1758 - mammals
   Order Sirenia Gill, 1872 - sea cows
     Family Dugongidae Gray, 1821 - dugong and sea cow
       1 Genus Dugong Lacépède, 1799 - dugong
       2 Genus ‡Hydrodamalis Retzius, 1794 - Steller's sea cow, great northern sea cow