Striking hummingbird with extremely long tail. Male is mostly emerald green with blue-green throat and long forked tail. Female is much different, with shorter tail, spotted throat, buffy belly, and short white mustache stripe. Primarily found on the east slope of the Andes from Venezuela to Bolivia, in foothills and subtropical zones from 1,200–2,500 m. Occurs within cloud forest and at edges; visits feeders. Male is superficially similar to trainbearers but note different habitat.