I saw this hummingbird at a distance, followed it with with my eyes for a while, and suddenly landed it in the tree next to me. It turned out to be a Glittering-bellied emerald, a hummingbird that is relatively common in drier areas and in the lowlands of eastern and southeastern Bolivia. It has a distinctly red bill with a black tip. This is a male, the female has a gray neck and a white tail tip. As you can discern from this picture, the male also has a small, white spot just behind the eye. The pointed bill is indispensable because this bird feeds on nectar of blooming Tabebuia, Eucalyptus and Jacaranda acutifolia by penetrating the petals all the way down to the base.