Cook's swift (Apus cooki)

Cook's swift (Apus cooki) is a small bird in the swift family Apodidae.
Cook's swifts breed in limestone caves of Thailand, Myanmar and Indochina. 

Apodidae, Apus is Latin for a swift, thought to be a type of swallow with no feet (from Ancient Greek a meaning "without", and pous meaning "foot", Greek apous meaning "footless").