Limestone Leaf-warbler: A new warbler for Vietnam and Laos
A new species of warbler found in the karst limestone country of central and northern Vietnam and adjoining regions in Laos was described in the January issue of Ibis, the international journal of avian science published by the British Ornithologists Union.
The Limestone Leaf-warbler (Phylloscopus calciatilis), is very similar to Sulphur-breasted Warbler (Phylloscopus ricketti) in appearance, but is slightly smaller with a proportionately larger bill and rounder wings. Its song and calls however are diagnostic.
The bird was initially identified as a Sulphur-breasted Warbler, but later it was realised that its songs differed markedly from the songs of the Sulphur-breasted warbler, and further studies were undertaken.