Utility of cytochrome c oxidase I for the deciphering of unstable phylogeny and taxonomy of gorals, genus Nemorhaedus Hamilton Smith, 1827 (Bovidae, Ovibovina)

Abstract

Gorals represent ungulate mammals of the Palearctic and Indo-Malayan realms that face habitat destruction and intense hunting pressure. Their classification has been the subject of various (mainly genetic) assessments in the last decade, but some results are conflicting, hampering some conservation-based decisions. Genetic sampling of gorals has increased considerably in recent years, at least for mitochondrial (mt) DNA. Results based on two mt genes (cytochrome b and the D-loop) are currently available. Still, the utility of cytochrome oxidase subunit I remains unanalysed, even though it belongs among the gene markers that enable a correct species identification in mammals. This study examines phylogenetic relationships and species delimitation in gorals using all currently available cytochrome oxidase subunit I sequences, including the not yet analysed goral population from Pakistan. Our results of various phylogenetic approaches, such as maximum parsimony, likelihood and Bayesian inference, and exploration of species boundaries via species delimitation support the validity of six species of goral, namely N. baileyi, N. caudatus, N. cranbrooki, N. evansi, N. goral, and N. griseus. This result accords well with results based on other mt genes, especially the cytochrome b from the highly exhaustive data sampling. Our study also summarises common sources of errors in the assessment of goral phylogeny and taxonomy and highlights future priorities in understanding goral diversification.