Class Mammalia Linnaeus, 1758 - mammals
   Order Primates Linnaeus, 1758 - primates
     Family Cercopithecidae Gray, 1821 - Old World monkeys
       Subfamily Colobinae Jerdon, 1867
         Genus Nasalis Geoffroy Saint-Hilaire, 1812 - proboscis monkey
           1 Nasalis concolor (Miller, 1903) - pig-tailed langur see Simias concolor Miller, 1903
           1 Subgenus Simias Miller, 1903 see Genus Simias Miller, 1903
           2 Subgenus Nasalis Geoffroy Saint-Hilaire, 1812 see Genus Nasalis Geoffroy Saint-Hilaire, 1812
           2 Nasalis larvatus (Wurmb, 1787) - proboscis monkey