The white-booted racket-tail (Ocreatus underwoodii) is a species of hummingbird in the "brilliants", tribe Heliantheini in subfamily Lesbiinae. It is found in Colombia, Ecuador, and Venezuela.
Taxonomy and systematics
The white-booted racket-tail, as defined by the International Ornithological Committee (IOC) and the Clements taxonomy, has five subspecies. They both include two more species in genus Ocreatus, the Peruvian racket-tail (O. peruanus) and the Rufous-booted racket-tail (O. addae). However, BirdLife International's Handbook of the Birds of the World (HBW) assigns the name "booted racket-tail" to O. underwoodii and includes those two taxa as subspecies of it. HBW also includes an eighth subspecies, O. u. annae. The South American Classification Committee of the American Ornithological Society (SACC) follows the eight-subspecies model but has requested a proposal to elevate puruanus, addae, and annae to species status.
The five subspecies recognized by the IOC are:
O. u. polystictus Todd (1942)
O. u. discifer Heine (1863)
O. u. underwoodii Lesson (1832)
O. u. incommodus Kleinschmidt (1943)
O. u. melanantherus Jardine (1851)
Male O. u. melanantherus, Ecuador
Female O. u. melanantherus, Ecuador
Description
All racket-tails have pronounced sexual dimorphism. Only the male has elongated outer rectrices (tail feathers). These tail feathers have bare shafts with long terminal oval flags. In all five subspecies of white-booted racket-tail those feathers are straight and do not cross; the flags slightly overlap. Both sexes of all have greenish upperparts without a glittering forehead, and all have white leg puffs. Males have a greenish gray throat and a solid green belly. Male white-booted racket-tails are 11 to 15 cm (4.3 to 5.9 in) long including the 7 to 8 cm (2.8 to 3.1 in) long outer tail feathers, and weigh 2.5 to 2.7 g (0.088 to 0.095 oz). Females are 7.6 to 9 cm (3.0 to 3.5 in) long and weigh 2.6 to...
