Blue-tailed hummingbird
The blue-tailed hummingbird is a species of hummingbird in the "emeralds", tribe Trochilini of subfamily Trochilinae. It is found in Costa Rica, El Salvador, Guatemala, Honduras, Mexico, and Nicaragua.
Taxonomy and systematics
The blue-tailed hummingbird was formerly placed in the genus Amazilia. A molecular phylogenetic study published in 2014 found that the genus Amazilia was polyphyletic. In the revised classification to create monophyletic genera, the blue-tailed hummingbird was moved by most taxonomic systems to the resurrected genus Saucerottia. However, BirdLife International's Handbook of the Birds of the World retains it in Amazilia.Three subspecies are recognized, the nominate S. c. cyanura, S. c. guatemalae, and S. c. impatiens.
Description
The blue-tailed hummingbird is long. One male specimen weighed and females weigh about. Both sexes of all subspecies have a black bill with a reddish base to the mandible. Males of the nominate subspecies have a deep metallic green crown and back, a dull purplish bronze rump, and dark metallic bluish uppertail coverts. Their primaries and secondaries are chestnut and show as a patch on the closed wing. Their tail is dark metallic violet blue. Their underparts are mostly bright metallic green with dull steel blue undertail coverts. Females are similar to males but duller. Their rump is less purplish and their underparts' feathers usually have narrow whitish margins. Their belly has some dull buffy whitish mixed in and their undertail coverts are grayish.Subspecies S. c. guatemalae is much darker than the nominate. The chestnut on the wings is darker, the tail's blue more violaceous to metallic purple, and the undertail coverts dark steel blue to blue-black. S. c. impatiens is somewhat larger than the nominate. Its head and back are darker green, the rufous or cinnamon patch on the wings is larger, and the undertail coverts are dull steel blue with rich ferruginous edges.