The Himalayan bluetail or Himalayan red-flanked bush-robin (Tarsiger rufilatus) is a small passerine bird that was formerly classed as a member of the thrush family Turdidae, but is now more generally considered to be an Old World flycatcher of Muscicapidae. While currently under review, this taxon is not current recognized as a species by BirdLife international.
It is a short-distance altitudinal migrant species, breeding in mixed coniferous forest with undergrowth at 3,000–4,400 m altitude in the Himalaya and wintering at 1,500–2,500 m. It is insectivorous. It is closely related to the red-flanked bluetail and was generally treated as a subspecies of it in the past, but as well as differing in its migratory behaviour (the red-flanked bluetail is a long-distance migrant), it also differs in the more intense blue colour of the adult males and the greyer colour of the females and juveniles. source