Also, the Isthmus group of Lampornis provides a glimpse at an intermediate stage in evolution, with one form ( L. These results are interesting, because they agree with a general trend for southern Mexican taxa (including to colonize the Isthmus and there form distinct species. It can be assumed though that Lampornis was present at the closing of the Isthmus of Panama, about 3.8 MYA, and that by that time, the northernmost lineage(s) had already diverged. García-Moreno's team refrains to date the emergence of the genus because of the absence of fossils or other robust evidence. It is intermediate in appearance between Lampornis and those species.
The garnet-throated hummingbird, which is sometimes considered to be the closest relative of the mountaingems, is indeed not distantly related to the group, but closer to the Eugenes hummingbirds. It might be closely related to the fiery-throated hummingbird, but these two species are very different at least morphologically. These results suggest that it is better placed in the monotypic genus Oreopyra, the relationships of which need more study. Most puzzling, however, is the fact that the white-bellied mountaingem constantly failed to form a monophyletic group with the other taxa. amethystinus may constitute two species, but not the violet-throated subspecies margaritae but the southernmost, red-throated forms are the most distinct ones. amethystinus, the northernmost species, is not as straightforward as assumed it is not clear whether they are each other's close relatives or whether the blue-throated hummingbird is the oldest lineage of the genus, the amethyst-throated hummingbird diverging later. Second, the exact relationship between the suspected sister taxa L. However, the speciation process is ongoing. However, the southern group has apparently evolved in a very short time and their conspicuous differences in appearance are not yet reflected in molecular divergence as mates are of course chosen according to their appearance and not their molecular differences, it seems prudent to split the group according to throat color as advocated by the American Ornithological Society. (2006) have largely confirmed the arrangement and the suspected evolutionary relationships, but a few surprising results have emerged:įirst, the white-throated mountaingem and the gray-tailed mountaingem are probably conspecific, but the purple-throated mountaingem seems to be a distinct species. Analysis of biogeography and mitochondrial and nuclear DNA sequences by García-Moreno et al. Like other hummingbirds, mountaingems also takes small insects as an essential source of protein.Ħ-8 species have been traditionally recognized, the main point of dispute being whether the southern forms which have fulvous-breasted females, found from Nicaragua to Panama, are one ( "variable mountaingem"), two, or three species. The food of this genus is nectar, taken from a variety of small flowers. Incubation takes 15–19 days, and fledging another 20–26. She lays two white eggs in a deep plant-fibre cup nest. The female mountaingem is entirely responsible for nest building and incubation. The females of some species also may differ significantly from the males in other plumage features. The males typically have green upperparts and a brightly coloured throat, which is a dull colour in the female. These are medium-sized to large (10–13 cm) hummingbirds with shortish slightly curved black bills. Mountaingems are a genus of hummingbirds, Lampornis, which inhabit mountainous regions from the south-western United States to the Isthmus of Panama. Purple-throated mountaingem ( Lampornis calolaemus) ♀ in Costa Rica
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