Bearded helmetcrest

The bearded helmetcrests (Oxypogon) are a genus of hummingbird in the family Trochilidae. They are found in Colombia and Venezuela. Primary natural habitat is subtropical or tropical high-altitude grassland, known as páramo. The genus contains four species.

Bearded helmetcrest
Green-bearded helmetcrest, Oxypogon guerinii
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Aves
Clade:	Strisores
Order:	Apodiformes
Family:	Trochilidae
Tribe:	Lesbiini
Genus:	Oxypogon Gould, 1848
Type species
Ornismya guerinii Boissonneau, 1840
Species
see text

Taxonomy and species list

The genus Oxypogon was introduced in 1848 by the English ornithologist John Gould.^[1] The type species was subsequently designated as the green-bearded helmetcrest.^[2][3] The genus name combines the Ancient Greek oxus meaning "sharp" or "pointed" with pōgōn meaning "beard".^[4]

The genus contains four species:^[5]

Genus Oxypogon – Gould, 1848 – four species

Common name	Scientific name and subspecies	Range	Size and ecology	IUCN status and estimated population
White-bearded helmetcrest	Oxypogon lindenii (Parzudaki, 1845)	Venezuela	Size: Habitat: Diet:	LC
Green-bearded helmetcrest	Oxypogon guerinii (Boissonneau, 1840)	Colombia	Size: Habitat: Diet:	LC
Blue-bearded helmetcrest	Oxypogon cyanolaemus Salvin & Godman, 1880	northern Colombia	Size: Habitat: Diet:	CR
Buffy helmetcrest	Oxypogon stuebelii Meyer, AB, 1884	Colombia	Size: Habitat: Diet:	VU

These four species were formerly all considered as subspecies of what was known as the bearded helmetcrest (Oxypogon guerinii). The bearded helmetcrest was split into four separate species based on a study of biometric and plumage data published in 2013.^[5][6]

A study of mitochondrial DNA of hummingbirds shows it to be most closely related to the bearded mountaineer (Oreonympha nobilis) and the rufous-capped thornbill (Chalcostigma ruficeps). The other member of the genus Chalcostigma lay outside the group, suggesting the genus might need revising in the future.^[7]

Description

The most common species, the white-bearded helmetcrest, measures 11.4 cm (4.5 in) in length, it is a small hummingbird with a very small 8 mm (0.31 in) bill. The adult male has a distinctive pointed black crest and a shaggy white beard. The face and cheeks are blackish, rendering a triangular shape with the white fronted crest and white beard. The underparts are a dull green-grey. The female lacks the beard and crest.^[8][9]

The species of bearded helmetcrests are found in the Andes, ranging from altitudes of 3,600 to 4,500 m (11,800 to 14,800 ft) in Venezuela,^[9] and 3,200 to 5,200 m (10,500 to 17,100 ft) in Colombia.^[8] Its main habitat is the páramo, but can descend to the treeline outside of breeding season.^[9]

All species often perch on boulders and flit between low-flowering shrubs, visiting the flowers of the genera Espeletia, Echeveria, Siphocampylus, Castilleja and Draba.^[9]

All species breed during the rainy season, and nest in the daisy Espeletia or build a nest of material from the daisy in a cliff or bank.^[9]