Bearded Helmetcrest

The Bearded Helmetcrest (Oxypogon guerinii) is a species of hummingbird in the family Trochilidae. It is found in Colombia and Venezuela. Its natural habitat is subtropical or tropical high-altitude grassland, known as páramo.

First described by French ornithologist Auguste Boissonneau in 1840, it is the only member of the genus Oxypogon. However, 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.

Measuring 114 mm (4.5 in) in length, it is a small hummingbird with a very small 8 mm (0.3 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.

The Bearded Helmetcrest is found in the Andes, ranging from altitudes of 3600 to 4500 m (12000–15000 ft) in Venezuela, and 3200 to 5200 m (10500 to 17000 ft) in Colombia. Its main habitat is the páramo, but can descend to the treeline outside of breeding season.

The Bearded Helmetcrest often perches on boulders and flits between low-flowering shrubs, visiting the flowers of the genera Espeletia, Echeveria, Siphocampylus, Castilleja and Draba.

The species breeds during the rainy season, and nests in in the daisy Espeletia or builds a nest of material from the daisy in a cliff or bank.