The white-bellied mountaingem or white-bellied mountain-gem (''Lampornis hemileucus'') is a species of

hummingbird Hummingbirds are birds native to the Americas and comprise the biological family Trochilidae. With about 361 species and 113 genera, they occur from Alaska to Tierra del Fuego, but the vast majority of the species are found in the tropics aro ...

in tribe Lampornithini of subfamily Trochilinae. It is found in

Costa Rica Costa Rica (, ; ; literally "Rich Coast"), officially the Republic of Costa Rica ( es, República de Costa Rica), is a country in the Central American region of North America, bordered by Nicaragua to the north, the Caribbean Sea to the no ...

and Panama.HBW and BirdLife International (2020) ''Handbook of the Birds of the World and BirdLife International digital checklist of the birds of the world'' Version 5. Available at: http://datazone.birdlife.org/userfiles/file/Species/Taxonomy/HBW-BirdLife_Checklist_v5_Dec20.zip xls zipped 1 MBretrieved 27 May 2021

Taxonomy and systematics

The white-bellied mountaingem is monotypic. There is some evidence that it does not belong in genus ''Lampornis''.García-Moreno, J., Cortés, N., Garcia-Deras, G.M. and Hernández-Baños, B.E. (2006). Local origin and diversification among ''Lampornis'' hummingbirds: a Mesoamerican taxon. Mol. Phyl. & Evol.. 38(2): 488–498.

Description

The white-bellied mountaingem is long. Males weigh about and females . Both sexes have a medium-length black bill, a long white stripe behind the eye, and pinkish feet. Adult males' face and crown are glittering green, much of the rest of the upperparts bronzy green, and the uppertail

coverts A covert feather or tectrix on a bird is one of a set of feathers, called coverts (or ''tectrices''), which, as the name implies, cover other feathers. The coverts help to smooth airflow over the wings and tail. Ear coverts The ear coverts are sm ...

bronzy. The tail is also bronzy, with dusky gray bands near the end of the outer feathers. The

gorget A gorget , from the French ' meaning throat, was a band of linen wrapped around a woman's neck and head in the medieval period or the lower part of a simple chaperon hood. The term later described a steel or leather collar to protect the thro ...

is blue-violet and the rest of the underparts white with green speckles along the sides. Adult females are similar, but the face and crown are less glittering and the throat is white with green speckles. Juveniles of both sexes have rusty fringes on the green feathers; males have a dull bronze gorget.Stiles, F.G. and P. F. D. Boesman (2020). White-bellied Mountain-gem (''Lampornis hemileucus''), version 1.0. In Birds of the World (J. del Hoyo, A. Elliott, J. Sargatal, D. A. Christie, and E. de Juana, Editors). Cornell Lab of Ornithology, Ithaca, NY, USA. https://doi.org/10.2173/bow.wbmgem1.01 retrieved 16 May 2022

Distribution and habitat

The white-bellied mountaingem is found on the Caribbean slope from north-central Costa Rica south and east into western Panama as far as Veraguas Province, and also locally on the Pacific slope in Panama. It inhabits the canopy of cool and very wet subtropical forest and also occurs at the shrub level at the forest edge and in gaps and clearings. It mostly shuns

secondary forest A secondary forest (or second-growth forest) is a forest or woodland area which has re-grown after a timber harvest or clearing for agriculture, until a long enough period has passed so that the effects of the disturbance are no longer evident. ...

and other semi-open landscapes.

Behavior

Movement

At least in Costa Rica, the white-bellied mountaingem breeds between of elevation and after breeding descends to between .

Feeding

The white-bellied mountaingem forages for nectar in flowering trees and shrubs, and is especially partial to

epiphyte An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

s of family Ericaceae and genus '' Columnea''. It is aggressive when feeding; males dominate most other hummingbirds, even larger ones, at clumps of flowering epiphytes. In addition to nectar, it also feeds on insects captured by

hawking Hawking may refer to: People * Stephen Hawking (1942–2018), English theoretical physicist and cosmologist *Hawking (surname), a family name (including a list of other persons with the name) Film * ''Hawking'' (2004 film), about Stephen Haw ...

; females sometimes glean arthropods from foliage.

Breeding

The white-bellied mountaingem breeds between August and March in Costa Rica. Its nest and details of its breeding

phenology Phenology is the study of periodic events in biological life cycles and how these are influenced by seasonality, seasonal and interannual variations in climate, as well as environmental factor, habitat factors (such as elevation). Examples includ ...

have not been described.

Vocalization

The white-bellied mountaingem's song is "a medley of squeaks, dry or liquid trills, and sputtering notes." When chasing it makes "squeaky sputtering trills". Other calls include "a repeated, somewhat nasal 'deep' ndrattling sequences 'de-de-drrrrr'."

Status

The

IUCN The International Union for Conservation of Nature (IUCN; officially International Union for Conservation of Nature and Natural Resources) is an international organization working in the field of nature conservation and sustainable use of natu ...

has assessed the white-bellied mountaingem as being of Least Concern, though it has a somewhat restricted range and its population size and trend are not known. It is considered locally common and much of its habitat remains intact, especially in three Costa Rican national parks.

References

{{Taxonbar, from=Q27074784 white-bellied mountaingem Birds of the Talamancan montane forests white-bellied mountaingem white-bellied mountaingem Taxonomy articles created by Polbot