Black-bellied Thorntail Hummingbird Species

The Black-bellied Thorntail (Discosura langsdorffi) is a small species of hummingbird found in South America. With its metallic green upperparts, white underparts, and distinctive black belly, it is one of the more striking members of its family. This article will provide an overview of the Black-bellied Thorntail, including its identification, distribution, habitat, diet, behavior, reproduction, conservation status, and key facts.


The adult male Black-bellied Thorntail has vibrant, shining green upperparts and crown, with a bold black belly that contrasts sharply with the clean white undertail coverts and breast. The black belly extends onto the flanks as well. The tail is mostly black with white outer corners. The bill is straight and black. Females are similar but less vibrantly colored, with more gray wash on the underparts. Juveniles resemble adult females but have buff scalloping on the underside.

In South America, the Black-bellied Thorntail’s striking appearance means it is unlikely to be confused with any other hummingbird species within its range. The somewhat similar White-vented Plumeleteer lacks the thorntail’s black belly and white undertail.

Distribution and Habitat

The Black-bellied Thorntail is found across northern and central South America. Its range extends from eastern Panama across northern Colombia and Venezuela, south as far as Bolivia and central Brazil. It occurs in a wide variety of wooded and forested habitats up to elevations of 3000 m. This includes lowland rainforest, foothill forest, gallery forest, savanna woodland, andsemi-open areas including parks and gardens.


Like all hummingbirds, the Black-bellied Thorntail feeds on flower nectar and tiny insects. It favors flowers with sturdy corollas to support its weight as it hovers while feeding. Some favorite food plants include shrubs such as fuchsia and ABIamanda, and small trees including Erythrina and Inga. The thorntail will aggressively defend nectar-rich food sources from other hummingbirds. To obtain insects, it hawks flying prey and gleans from flowers and leaves.


The Black-bellied Thorntail is solitary and territorial. Males establish feeding territories to monopolize flower resources. They advertise and defend territories by making display flights and aggressive chases. Courtship displays by the male involve flying in repeated oval patterns above the female. Outside of the breeding season, these hummingbirds may form loose flocks at favored feeding areas. They have a direct flight with bursts of rapid wingbeats alternated by glides.


The breeding season of the Black-bellied Thorntail varies across its range, typically coinciding with peak flower availability. Courtship flights lead to mating, after which the female constructs a small cup nest on a low horizontal branch, often over water. She builds the nest out of plant down bound with spider silk, and typically lays two white eggs. Incubation lasts 15-19 days. The chicks hatch with stubby bills and minimal down. They are fed regurgitated insects and nectar by the female and fledge in about 20-26 days.

Conservation Status

With its large range and presence in protected areas, the Black-bellied Thorntail is evaluated as Least Concern on the IUCN Red List. However, habitat loss is leading to population declines in some regions, especially Central America. The species has disappeared from many areas of its former range in Panama. Ongoing deforestation across South America may threaten populations in the future.


– The Black-bellied Thorntail is named for its pointed outer tail feathers. These project beyond the square tail tip like thorns.

– The species was first described by German naturalist Johann Hermann in 1783. Its scientific name langsdorffi honors Georg Heinrich von Langsdorff, a Russian naturalist who explored Brazil.

– Male Black-bellied Thorntails use their slender curved bill to steal nectar from females as they are feeding. This is called kleptnectarizing.

– The flight speed of a Black-bellied Thorntail has been measured at up to 93 km/h (58 mph) during territorial chases.

– To conserve energy overnight, Black-bellied Thorntails go into torpor, lowering their body temperature and metabolic rate.

In summary, the beautiful Black-bellied Thorntail is a charismatic hummingbird species found widely across northern South America. Its striking plumage patterns make it a jewel among its kind. While still common in many regions, habitat loss poses an increasing threat, making ongoing conservation measures important for this and many other hummingbirds. With a range of interesting behaviors and adaptations, the Black-bellied Thorntail illustrates the remarkable diversity of the hummingbird family.