The Red-tailed Comet (Sappho sparganura) is a medium-sized hummingbird found in the central Andes of Bolivia and Argentina.
The male has a spectacular, long, iridescent, golden-reddish tail.
Common to frequent in the woodlands and scrub typical of the dry Interandean valles extended up into Polylepis forests, and into the shrubby transition zones to high elevation puna or the moister cloud forests. Frequently around human habitation in agricultural areas, cities and towns.
In at least part of its range it is known in the local Quechua language as "Q'ori Kenti" ("golden hummingbird"). The genus name refers to Sappho, an ancient Greek poet of Lesbos.