This hummingbird lives in Andean mountain forest. Males flash a very long blue-green tail and look markedly different from females.
Males are about 17 cm long, with a long forked blue-green tail and blue throat. Females are about 10.5 cm, with a shorter green tail, white-spotted throat and breast, and a rufous wash on the belly.
It is recorded in eastern Andean mountain forest at about 1,200–2,500 m and feeds on flower nectar.
An extinction-risk assessment has not been added yet.