Integrative taxonomy confirms the species status of the Himalayan langurs, <i>Semnopithecus schistaceus</i> Hodgson, 1840
Kunal Arekar, Sambandam Sathyakumar, K. Praveen Karanth
Abstract
Taxonomy is replete with groups where the species identity and classification remain unresolved. One such group is the widely distributed Hanuman langur (Colobinae: Semnopithecus). For most part of the last century, the Hanuman langur was considered to be a single species with multiple subspecies. Nevertheless, recent studies using an integrative taxonomy approach suggested that this taxon is a complex, with at least three species. However, these studies did not include the Himalayan population of the Hanuman langur whose taxonomic status remains unresolved. The Himalayan population of Hanuman langurs has been classified as a distinct species with multiple subspecies or been subsumed into other species. These classification schemes are wholly based on morphological characters which are sometimes insufficient to delimit different species. Here, we have integrated data from multiple sources viz. morphology, DNA, and ecology to resolve the taxonomy of the Himalayan langur and to understand its distribution limit. Our results with three lines of evidence corresponding to three different species concepts show that Himalayan langur is a species distinct from Semnopithecus entellus of the plains. Additionally, these results did not show any support for splitting of the Himalayan langur into multiple subspecies. Our study supports the classification proposed by Hill (Ceylon Journal of Science, XXI, 1939) and we recommend Semnopithecus schistaceus Hodgson, 1840 as species name for the Himalayan langur and subsume all the known subspecies into it.