Puna Thistletail

The puna thistletail is 17 to 18.5 cm (6.7 to 7.3 in) long and weighs 13 to 17 g (0.46 to 0.60 oz). The sexes have the same plumage. Adults have a brownish gray face with a grayish supercilium. Their crown is dark rufescent-brown with a grayer forehead. Their back, rump, and wings are dark rufescent brown. Their tail is a brighter rufescent brown; it is long and deeply forked with few barbs at the feather ends. Their chin is white, in some areas with a small rufous center. Their throat has a blackish patch with pale gray flecks. Voice: The puna thistletail is highly vocal. Their song, sung by both sexes, is "a short, rapid high-pitched series of spluttering notes, pee-peep-p-p-p-t-t-tii...that accelerates and increases in volume before fading at the end". Its call is "a sharp pyeek, preek, peent or feet note".