Class Mammalia Linnaeus, 1758 - mammals
   Subclass Theria Parker & Haswell, 1897
     Order Primates Linnaeus, 1758 - primates
       Suborder Haplorrhini Pocock, 1918 see Suborder Haplorhini Pocock, 1918
         Infraorder Simiiformes Haeckel, 1866
           Parvorder Catarrhini Geoffroy Saint-Hilaire, 1812
             Superfamily Cercopithecoidea Gray, 1821
               Family Cercopithecidae Gray, 1821 - Old World monkeys
                 Subfamily Colobinae Jerdon, 1867
                   Genus Trachypithecus Reichenbach, 1862 - brow-ridged langurs, leaf monkeys
                     Trachypithecus obscurus (Reid, 1837)
                       1 [Trachypithecus obscurus obscurus]ᵀ (Reid, 1837)
                       2 Trachypithecus obscurus carbo (Thomas & Wroughton, 1909)
                       3 Trachypithecus obscurus flavicauda (Elliot, 1910)
                       4 Trachypithecus obscurus halonifer (Cantor, 1845)
                       5 Trachypithecus obscurus sanctorum (Elliot, 1910)
                       6 Trachypithecus obscurus seimundi (Chasen, 1940)
                       7 Trachypithecus obscurus styx (Kloss, 1911)