The Golden spectacled Warbler: a complex of sibling species, including a previously undescribed species

The Golden-spectacled Warbler, usually treated as a single species, Seicerc us burkii, is widely distributed in mountains of southern Asia. We argue th at it should be treated as five different species, one of which is describe d here for the first time. Two species occur in sympatry in the Himalayas. The other three species are found in eastern Asia, where all three are symp atric in China, and two of these breed sympatrically also in Vietnam. In Bu rma and adjacent parts of India, one of the Himalayan species is sympatric with one of the east Asian species. We describe differences in morphology, vocalizations, altitudinal distribution and habitat between these five spec ies, as well as results from playback tests, which show that all sympatric taxa differ and appear to be reproductively isolated from each other.