Dark blue metallic upperparts, deep red forehead and throat and light underparts. Long tail-streamers in adults and deeply forked tail. Both the metallic blue and the deep red appears black at a distance. Combination of dark throat/breast and light underparts and vent is diagnostic, and distinguishes it both from Red-rumped Swallow and the smaller martins. Juveniles are less brightly coloured with a dull red throat, and short streamers.

Characteristic calls and song. Contact call a short and sharp "weet" or "kee-weet". Song a sparkling, squeaky energetic improvisation with interspersed contact calls, often with diagnostic ending; an electric and drawn-out "su-eerrrrrrrrrrrrrrr".

Song:

Wikipedia: map (se also Xeno-canto below)

Birdlife ecology

Observation.org Latest observations

Video IBC

Image search Flickr NB! May give other species

Sound search at Xeno-canto

Featherbase