White-browed Tit-warbler (Leptopoecile sophiae) - HBW 13, p. 101

Taxonomy: Leptopoecile Sophiae Severtsov, 1873, Lake Issyk-Kul', Tien Shan, Kyrgyzstan.
Relationships of genus uncertain; formerly placed in family Sylviidae, and recent studies based on mitochondrial DNA indicate that it groups with members of present family within a sylvioid assemblage that includes tits and chickadees (Paridae). Further research required. Precise geographical boundaries of races not well known, and review needed. Races divisible into two groups, one with relatively dark plumage (nominate and obscurus) and the other pale (major and stoliczkae); combined ranges of dark races form a ring that almost entirely encircles those of pale races, and has been suggested that groups are separated ecologically, with darker “nominate group” at higher elevations in relatively moist subalpine scrub and adjoining forest and paler “stoliczkae group” confined to well-wooded arid montane terrain at lower altitudes (at least where the groups overlap); if this ecological separation were confirmed, the two groups would be best treated as separate species. Nominate race intergrades with obscurus in the NE Qinghai and adjacent Gansu region of C China. Four subspecies recognized.