Eastern Red-rumped Swallow (Nhạn bụng xám, Cecropis daurica)

The eastern red-rumped swallow (Cecropis daurica) is a small passerine bird in the swallow family Hirundinidae. 
The bird is found in open, often hilly, areas with clearings and cultivation across Southeast Asia to north-eastern India and Taiwan.

The alternative genus Hirundo is the Latin word for "swallow".
The name of the genus Cecropis is from the Ancient Greek Kekropis "Athenian woman".
The specific daurica is derived from Dauria, a mountainous region to the east of Lake Baikal in Russia.