In China, Blyth’s Leaf Warbler Phylloscopus reguloides assamensis breeds southeast Tibet to northern Yunnan, southern Sichuan, and eastern Guizhou. Nominate possibly in Ngari and Shigatse prefectures in Himalayan foothills of Tibet. Very similar to Claudia’s Leaf Warbler P. claudiae and Hartert’s Leaf Warbler P. goodsoni, and perhaps not safely separable in field. May be distinguished from Claudia’s by darker green upperparts and by yellower crown-stripe, ear coverts, and underparts. Does not show persistent nuthatch-like behavior typical of Claudia’s. Voice very similar to Claudia’s. Call often ends with a clear whistled pit-chew-chee. — Craig Brelsford
Daniel Bengtsson served as chief ornithological consultant for Craig Brelsford’s Photographic Field Guide to the Birds of China, from which this species description is drawn.