The male of this species is known to produce a unique mechanical sound with its highly modified secudar feathers. It was previously classified in the genus Allocotopterus. Its name Machaeropterus comes from the Greek roots makhaira = knife or dagger and pteros = winged. The epithet deliciosus comes from Latin and means delicate.
It is 9.5 to 10 cm lenght. It has dark brown irises, black bill, and flesh-gray legs. The male presents the anterior part of the crown of scarlet color, dark eye stria and the rest of the body mainly brown with a paler head and throat. Its belly is darker, it has some white mixed in the flanks, rump and blackish supracaudal coverts, scapulars, tail and black wings, the latter with a lot of white, especially in the internal secondaries. Its secondary feathers are highly modified, progressively from the outermost feather to S7 and then decreasingly from S8 to S10, presenting thickened and folded rachis near the apex providing a ruffled appearance. The female is olive above with a cinnamon tint on the face and internal remiges with white margins. It has a whitish throat, olive-yellowish chest and flanks, and a pale yellow belly. Young individuals are similar to the female.
The female is distinguished from other females in the family because she has white on her wings and a cinnamon tint on her face.
It is considered a monotypic species.
It is distributed along the western slope of the Andes from the center-west of Colombia to the west of Ecuador. In Colombia, it is found on the western slope of the Western Cordillera from the limits between the departments of Risaralda and Chocó towards the south of the country to the limits with Ecuador.
Its habitat is very humid montane forests with abundant moss cover. It also uses forests in advanced secondary succession.
It feeds on fruits and insects. In a study carried out in Ecuador, individuals were observed fluttering next to the clusters of berries of a Melastomataceae.
In Colombia, egg laying has been recorded in March and August. Their nest is a small, deep hanging cup of plant fibers, externally covered with moss. He builds it on the bifurcation of a bush branch at a height ranging from 0.5 to 1.2 m. The size of its clutch is 2 eggs. The incubation and development period of the hatchlings remains undocumented.
Usually solitary and occasionally with mixed flocks. It forages in the middle or lower stratum of the vegetation where it captures insects on leaves or twigs by means of aerial exits. Males maintain territories within lek aggregations and make solitary displays throughout the year at distances that can be heard from each other, generally on thin branches that do not exceed 7 m in height above the ground. The unfolds consist of rapid wing movements, producing the effect of a black and white flash, after which they rotate the wings downwards, generating a mechanical sound with the tips of the secondary feathers.
Formerly classified in the monotypic genus Allocotopterus based on its highly modified secondary feathers.
At the national and international level, it is classified as a species of least concern.
The mechanical sounds produced by this species are acoustically unique as they are longer in duration and present harmonically related pure tones.
Avibase. 2016. Machaeropterus deliciosus. Descargado de http://avibase.bsc-eoc.org/species.jsp?avibaseid=08F2D7DF1FF6B4A3 el 09/01/2013
BirdLife International (2013) Species factsheet: Machaeropterus deliciosus. Descargado de http://www.birdlife.org/datazone/speciesfactsheet.php?id=4573 el 09/01/2013.
Bostwick, K. S. 2000. Display behaviors, mechanical sounds, and evolutionary relationshipc of the Club-winged MAnakin (Machaeropterus deliciosus). The Auk 117(2):465-478.
Hilty, S. L. y W. L. Brown. 2001. Guía de las Aves de Colombia. Princetn. Univ. Press, Princeton, NJ