Named limestone leaf-warbler Phylloscopus calciatilis, the new species is very similar to the sulphur-breasted warbler P. ricketti, in morphology, but it is smaller with a proportionately larger bill and rounder wing. Its song and calls are diagnostic. Based on mitochondrial and nuclear DNA, the new species is most closely related to P. ricketti and the yellow-vented warbler P. cantator.
Credit to Swede
“Although this was a collective effort involving a number of institutions and individuals I would like to pay particular tribute to Per Alstrom, the lead author who undertook most of the hard work, research and analysis in putting this together,” said Jonathan Eames, Programme Manager of BirdLife International in Indochina.
Initially, the bird was identified as a sulphur-breasted warbler, in itself an interesting finding, since it was apparently breeding more than 1,000km south of its previously known breeding areas in China. Later it was realised that its songs differed markedly from the songs of the sulphur-breasted warbler, and further studies were undertaken. The BirdLife and Institute of Ecology and Biological Resources authors provided proof that the species was a resident breeding species in the karst limestone region of central Vietnam. The type description of the species is published in the latest issue of the Ibis, the international journal of avian science published by the British Ornithologists Union.
“The karst limestone regions of Laos and Vietnam are noted for their levels of plant, invertebrate and mammal diversity. It is however, only relatively recently that its importance for bird diversity has begun to be appreciated,” said Eames.