Adult Characteristics: A prominent large black patch is present anterior to the eye, with a white spot preceding it. The forehead, crown, nape, wings, upper tail coverts, tail, flanks, and rump exhibit a black coloration with a slight steel-blue sheen. The mid-back is brown, gradually blending with the surrounding black. A streak is observed on the flanks below the tail, with the upper thigh being white. The remaining ventral surface is dark brown, with the base of the feathers on the chin and throat being slightly lighter in color and often visible. The tail feathers taper to a point rather than being rounded, unlike those of Chaetura cochinchinensis.
The eyes are dark brown. The legs are pinkish-gray or reddish-brown.
Measurements:
- Wing: 185 – 207 mm
- Tail: 54 – 59 mm
- Tarsus: 16 mm
- Bill: 8 – 9 mm
Distribution:
This swift species is distributed in Assam, South India; Burma, Southern Thailand, the Andaman Islands, Indochina, and North Malaya.
Vietnam: This species is commonly found in Southern Vietnam, where they often build nests within large rock crevices deep within forests. Outside of the breeding season, they may be observed flying in large flocks.