Slender-tailed woodstar Microstilbon burmeisteri

Small, long-tailed hummingbird of NW Argentina and the Bolivian Andes. Prefers humid and semi-humid middle elevation forests, but generally rare and difficult to find throughout its distribution. Told from White-bellied Woodstar by Slender-tailed’s longer tail, accentuated sides to gorget, and, on females, largely orangey underparts.