Unusually dark hummingbird endemic to the high Andes of Peru. Plumage is mostly black with subtle hints of red and green. The tail is coppery when seen in good light, and it has a small white spot behind the eye. Adult male has a glittering green throat patch, which is smaller in females and absent in immature birds. Inhabits dense scrub and short forest. Often gives high-pitched, piping squeaks, either alone or in a short, descending series.