- Lampornis viridipallens
Identification
11–12 cm
This species is generally quite easy to identify because the features can all be seen without the need for direct lighting to show the colours. It is a fairly large hummingbird with a medium length, straight bill that is all dark. In all plumages, there is a bold white stripe behind the eye. The outer tail feathers are grey in colour, though this is generally only seen as the bird spreads its tail in flight. In males there is a distinct green gorget, which looks all dark when the light is not shining directly on it. The female has an all white throat.
Similar Species
Green-throated Mountain Gem is allopatric from the closely related Green-breasted Mountain Gem, but in places there is only 50km separating populations so there is the possibility of wandering birds (though this has never been reported) causing identification problems or where the observer is uncertain about the location of the line separating the populations.
Male Green-throateds have green throats, sharply contrasting white breasts, and have greyish outer tail feathers. Male Green-breasted are entirely green below or with limted amounts of white, usually with no visible demarcation between the gorget and the rest of the underparts, and have a distinct white tail flash.
Female Green-breasteds generally have the throat entirely buff, while the throat of Green-throated is white at all ages.
The closely related and sympatric Amethyst-throated Mountaingem has a distinctly down-curved bill, compared with the straight bills of the two Mountain-gem species.
Rivoli's Hummingbird has a much longer bill and a white post-occular spot rather than the white stripe of Green-throated.
White-eared Hummingbird is smaller and has a red bill.
Distribution
This species has a tiny world distribution that is limited to the highlands of Honduras west of the Sula Valley, El Salvador, southern Guatemala and southern Mexico, in the states of Chiapas and just into Oaxaca. Although the range is restricted, it is one of the most commonly seen hummingbirds in suitable habitat throughout its range.
Taxonomy
This species has sometimes been lumped with Green-breasted Mountain-gem Lampornis sybillae which inhabits similar habitats to the east of the Sula Valley in Honduras and western Nicaragua. The two are currently classified as separate species by the AOU. A discussion of the two forms is made by Monroe, B. L. Jr. (1963) A revision of the Lampornis viridipallens complex (Aves: Trochilidae). Occas. Papers Mus. Zool., Louisiana State Univ., no 27, pp1-10, discussed also in Monroe (1968) 'A distributional survey of the birds of Honduras'.
Subspecies
There are 4 subspecies[1]:
- L. v. amadoni:
- Southern Mexico (Cerro Baúl in Oaxaca)
- L. v. ovandensis:
- Highlands of southern Mexico (Chiapas) and north-western Guatemala
- L. v. viridipallens:
- Highlands of Guatemala, northern El Salvador and western Honduras
- L. v. nubivagus;
- Upper tropical El Salvador
Habitat
Mainly cloud forest, but also pine-evergreen forest. Especially abundant, or possibly just more easily observed, in edge and second growth habitat. Found in highlands between about 900 and 2700m (Howell and Webb 1995).
Behaviour
There have been very few studies of this species. Ornelas et al (2002) made some studies of vocalisations and included a sonogram. Birds are sometimes found in loose leks, though there are no published studies of this.
Diet
Not well recorded, but they are thought to eat the nectar of similar plant species favoured by Amethyst-throated Mountaingem.
References
- Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2014. The eBird/Clements checklist of birds of the world: Version 6.9., with updates to August 2014. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
- Handbook of the Birds of the World Alive (retrieved January 2015)
Recommended Citation
- BirdForum Opus contributors. (2021) Green-throated Mountain-gem. In: BirdForum, the forum for wild birds and birding. Retrieved 13 May 2021 from https://www.birdforum.net/wiki/Green-throated_Mountain-gem
External Links
A page on this species with many photos can be found in the bird database of http://tomjenner.com/mayanbirding/thebirds_gre_thr_mount_gem.html
