Bugun Liocichla. (Reuters)

New Delhi, Sept. 12: An astronomer on vacation has discovered a strikingly coloured hitherto unknown bird with a distinct fluty song in western Arunachal Pradesh, the first new bird species from India in six decades.

The bird, observed earlier this year in the Eaglenest Wildlife Sanctuary in Arunachal Pradesh, has been described to have plumage with shades of olive, golden-yellow and crimson wings, and a bright yellow patch in front of the eye.

It has a black cap and red-tipped tail feathers with a flame-coloured underside. Astronomer Ramana Athreya who found the bird has named it Bugun Liocichla, after the Bugun tribe living on the periphery of the Eaglenest sanctuary.

“There’s no bird that looks even remotely similar to this one in India,” Athreya told The Telegraph from his office at the National Centre for Radio Astronomy in Pune.

He had first caught a glimpse of a pair of birds that did not appear to fit the description of any bird described from India in January 1995. He had spotted a flock of these birds again in January 2005.

But it was only in May 2006 that — with permission from forest authorities — Athreya netted a bird to briefly observe and photograph it before setting it free.

“What’s striking is that a bird so distinctive in appearance and vocaliation (song) has remained undiscovered until 2006,” Athreya said. “This bird is not particularly shy. There might be more species unknown to science in that area.”

The new species has been described in the journal Indian Birds. Liocichlas belong to a group of babbler species and a red-faced liocichla had been previously known from Arunachal Pradesh. Two liocichla species are found in China and Taiwan.

The known population of Bugun liocichla consists of just 14 birds, including three breeding pairs. The last bird species discovered in mainland India was the rusty-throated Wren-babbler in eastern Arunachal Pradesh in 1948.

The song of Bugun liocichla is very fluty with descending notes, Athreya said.

The song fragments may be transcribed in English as “weee-keew,” or “yu-weee-keew”, or a longer song — “weiu.i-wee.i-tuu.i-tuu.uw-tu.oow”.