Species delimitation is fundamental to many areas of biology, and in cases where taxonomic status has not been sufficiently clarified the ramifications can be as serious as extinction due to the failure to implement conservation measures. Since 1931, the Mountain Hawk Eagle Nisaetus (Spizaetus) nipalensis Hodgson has included the allopatric Sri Lankan and southern Indian taxon N. kelaarti (Legge) as a subspecies, and its taxonomic status has not been re-evaluated. We found that N. kelaarti differs considerably from N. nipalensis in its relatively much larger bill and claws and short primary projection, and that it also differs consistently in numerous plumage characters and other mensural characters. Its vocalizations differ distinctly, and an earlier study found a moderate degree of genetic differentiation (4.4% in cyt b and 3.1% in CR) from N. nipalensis. The available evidence thus strongly and unambiguously supports the specific distinctness of N. kelaarti.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.