Black-bellied Hummingbird

The black-bellied hummingbird (Eupherusa nigriventris) is a species of hummingbird in the "emeralds", tribe Trochilini of subfamily Trochilinae. It is found in Costa Rica and Panama. == Taxonomy and systematics == The black-bellied hummingbird is monotypic. It and the stripe-tailed hummingbird (E. eximia) are sister species. == Description == The black-bellied hummingbird is 7 to 8 cm (2.8 to 3.1 in) long and weighs about 3.0 to 3.5 g (0.11 to 0.12 oz). Males have a black breast and belly that provide the species' English name; their forehead and face are also black. The sides of the breast are green and the undertail coverts white. They have mostly bronze green upperparts with narrow black edges on the crown feathers and dull bronze uppertail coverts. Their central tail feathers are dull black with a bronze gloss and the outer ones white. The female has grayish white underparts with white undertail coverts. It has metallic bronze green upperparts that are more bronze on the uppertail coverts. Both sexes molt after breeding but males do so one to two months before the female. == Distribution and habitat == The black-bellied hummingbird is found through Costa Rica into western Panama, mostly on the Caribbean…