Class Mammalia Linnaeus, 1758 - mammals
   Order Primates Linnaeus, 1758 - primates
     Family Lemuridae Gray, 1821 - large lemurs
       Genus Hapalemur Geoffroy Saint-Hilaire, 1851 - gentle lemurs
         Hapalemur griseus (Link, 1795) - grey gentle lemur
           1 Hapalemur griseus alaotrensis see Hapalemur alaotrensis Rumpler, in Tattersall & Sussman, eds., 1975
           2 Hapalemur griseus griseusᵀ (Link, 1795)
           3 Hapalemur griseus occidentalis see Hapalemur occidentalis Rumpler, in Tattersall & Sussman, eds., 1975