Koepcke's hermit

Koepcke's hermit is 14 to 15 cm (5.5 to 5.9 in) long. Males weigh 4.7 to 5.8 g (0.17 to 0.20 oz) and females 4.5 to 4.9 g (0.16 to 0.17 oz). It is one of the few hermit hummingbirds with a nearly straight bill. It has a blackish crown glossed with greenish, a glossy greenish bronze nape, a glossy bronze back, and a rufous rump. The tail is mostly dark glossy green. The innermost pair of tail feathers are longer than the others and have white tips; the others have broad buffy rufous tips. The face has a black "mask" bordered with narrow white streaks. The chin and throat are white, the center of the breast pale reddish buff with grayer sides, and the belly and flanks a rich reddish buff.