About Collocalia affinis Beavan, 1867
Taxonomy and Naming
The plume-toed swiftlet, scientifically named Collocalia affinis Beavan, 1867, measures 9 to 10 cm (3.5 to 3.9 inches) in length and has a square tail.
Dorsal and Wing Coloration
Its back and the upper surface of its wings are uniformly dark greenish-blue with a moderate gloss.
Ventral Coloration
Its throat and upper breast are dark grey; this color blends into large greyish chevrons across the lower breast and flanks, and the belly area is usually white.
Toe Morphology
A tuft of small feathers grows on the hallux, the rear-facing toe of this bird.
Rump and Tail Markings
This species does not have a pale contrasting rump, and it also has no white spots on the inner webs of its tail feathers.