About Phylloscopus sindianus W.E.Brooks, 1880
The mountain chiffchaff, also called the eastern chiffchaff, with the scientific name Phylloscopus sindianus, is a species of leaf warbler. It has two recognized subspecies: P. s. lorenzii found in the Caucasus, and the nominate subspecies P. s. sindianus found in the Tian Shan. This species is an altitudinal migrant, which means it moves to lower elevations during the winter season. The nominate subspecies resembles the Siberian chiffchaff, but can be distinguished by its finer, darker bill, browner upperparts, and buff flanks. Its song is almost identical to that of the common chiffchaff, while its call is a weak psew. The subspecies P. s. lorenzii is a warmer and darker shade of brown than the nominate race. It lives in sympatry with the common chiffchaff in a small area of the Western Caucasus, and interbreeding between the two happens rarely, if at all. The mountain chiffchaff differs from tristis in its vocalizations, external physical features, and mtDNA sequences. The two subspecies of mountain chiffchaff are visibly distinct in their vocalizations, and also show some differences in their mtDNA sequences.
