Yellow-billed tit-tyrant
The yellow-billed tit-tyrant is a species of bird in subfamily Elaeniinae of family Tyrannidae, the tyrant flycatchers. It is found in Argentina, Bolivia, Chile, Peru, and as a vagrant in Uruguay.
Taxonomy and systematics
The members of genus Anairetes are known commonly as tit-tyrants because their active foraging behavior and crests are reminiscent of the true tits in the family Paridae. The genus had formerly been named Spizitornis.The yellow-billed tit-tyrant has these four subspecies:
- A. f. huancabambae
- A. f. arequipae
- A. f. cuzcoensis
- A. f. flavirostris Sclater, PL & Salvin, 1876
Description
The yellow-billed tit-tyrant is long and weighs. The sexes have the same plumage. Adults of the nominate subspecies A. f. flavirostris have a blackish split crest formed by elongated feathers on the sides of the crown. Their forecrown is dusky gray with faint white streaks, the rest of their crown is white, their supercilium is white, and the rest of their face is white with bold black streaks. Their upperparts are medium gray-brown with faint blackish streaks. Their wings are blackish with buffy white tips and edges on the inner flight feathers. Their wing coverts have cinnamon-buff tips that show as two bars on the closed wing. Their tail is dusky brownish with paler outer webs on the outermost pair of feathers and paler tips on the others. Their throat, breast, and upper belly are white with bold black streaks and their flanks, lower belly, and undertail coverts are unmarked yellowish. Juveniles have a shorter crest than adults and are duller, more buffy, and not as strongly streaked.Subspecies A. f. huancabambae has more white in the crown than the nominate; its back is dark brown with strong blackish streaks and their tail feather have white edges and tips where the nominate is pale brownish. A. f. arequipaes tail feathers have dull brownish edges and tips only slightly paler than the rest of the tail; its belly is less yellowish than the nominate's. A. f. cuzcoensis is the largest subspecies and has the least amount of white on its crown. Its back is darker brown and more heavily streaked than the nominate's and its breast has wider and darker streaks. Both sexes of all subspecies have a dark brown iris, a black maxilla, a yellow mandible with a black outer half or tip, and slate-gray to black legs and feet.
Distribution and habitat
The nominate subspecies of the yellow-billed tit-tyrant is the southernmost of the four. It is found in the Andes of Bolivia and western Argentina as far south as Chubut Province and east to Buenos Aires and Entre Ríos provinces. Subspecies A. f. huancabambae is found in the Andes of northern Peru from Piura and Cajamarca departments south to Ancash and Huánuco. A. f. arequipae is found on the western slope of the Andes from Peru's Lima Department south into northwestern Chile's Arica and Tarapacá regions. A. f. cuzcoensis is known only in Peru's Cuzco Department but its range might extend north to Junín Department. In addition, the South American Classification Committee of the American Ornithological Society has records showing the nominate subspecies as a vagrant in Uruguay.The yellow-billed tit-tyrant inhabits a variety of dryish semi-open to open landscapes. These include dry montane and desert scrublands, thorn scrub, semi-arid brush, and somewhat humid woodlands dominated by Polylepis and Gynoxys trees and shrubs. It occurs mostly at elevations between but west of the Andes is found locally almost at sea level, especially in coastal lomas "fog oases".