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 Hominoidea Gray, 1825
               Family Hylobatidae Gray, 1871 - gibbons
                 Genus Nomascus Miller, 1933
                   1 Nomascus concolor (Harlan, 1826)
                   2 Nomascus gabriellae (Thomas, 1909)
                   3 Nomascus hainanus (Thomas, 1892)
                   4 Nomascus leucogenys (Ogilby, 1840)
                   5 Nomascus siki Delacour, 1951