Jungle Nightjar

The jungle nightjar is about 21–24 centimetres long, with the Sri Lankan population smaller. It is mostly grey with black streaks on the crown and lacks a conspicuous wing patch, which is rufous. The tail is greyish with well-separated narrow black bars. The male has a white throat patch that is broken in the middle, and the female a rufous throat patch and submoustachial streaks. The usual call is a series of thacoo or chuck notes, five every two seconds, like a distant engine, and the song is a slow, regular series of notes repeated for as long as ten seconds. (Wikipedia, general species account)

This nightjar is found in the Indian subcontinent, mainly on the edge of forests, where it is seen or heard at dusk. The taxonomy of this and related Asian nightjars is complex and a range of treatments has been followed. It was formerly called the grey nightjar or Indian jungle nightjar, and sometimes included the East Asian grey nightjar as a subspecies. (Wikipedia, general species account)