TAXONOMY AND DISTRIBUTION OF PRESBYTIS-MELALOPHOS GROUP IN SUMATRA, INDONESIA

Taxonomy of the Presbytis melalophos group in Sumatera has been based solely on the distinction in the pelage coloration and has been a subject of controversy. In the present study, extensive field observations were undertaken. Three species, i. e. P. melalophos, P. thomasi, and P. femoralis, are recognized in Sumatera based on the cranial morphology, pelage coloration, and vocalization. Subspecies of each species are revised, a new classification is proposed, and a new subspecies, Presbytis melalophos bicolor, is described. A detailed distribution map of species and subspecies is presented. No sympatry occurs between the species. Finally, a cladistic analysis is presented for the three species, based on the cranial characters; the branching sequence is first between the P melalophos clade and the P femoralis- P. thomasi clade and second between the P. femoralis clade and the P. thomasi clade.