A new species of bird has been discovered in the Cambodian capital, Phnom Penh, a bustling city of 1.5 million people.

The Cambodian tailorbird is a grey bird about the size of a wren with a rust-coloured cap and a black throat. It was found both in the city itself and several locations just outside the city, including a construction site, by a team of scientists with the Wildlife Conservation Society, BirdLife International, the University of Kansas, Louisiana State University and the Sam Veasna Centre, said a news release from the New York-based Wildlife Conservation Society late Tuesday.

"The modern discovery of an undescribed bird species within the limits of a large populous city — not to mention 30 minutes from my home — is extraordinary," said Simon Mahood, a scientist with the Wildlife Conservation Society, and lead author of the scientific paper describing the new bird.

"The discovery indicates that new species of birds may still be found in familiar and unexpected locations."

The paper describing the bird is published in a special online issue of Forktail, the journal of the Oriental Bird Club.

The Cambodian tailorbird was first photographed at a construction site at the edge of Phnom Penh by Wildlife Conservation Society scientist John Ashish, who thought it was a similar, coastal species of tailorbird.

Mahood wasn't so sure, and did some further investigation, confirming it as a new species.

The new bird has been given the scientific name Orthotomus chaktomuk. "Chaktomuk" is an old word in Khmer, the official language of Cambodia, that means "four faces," describing where the bird was found — an area where the Tonle Sap, Mekong and Bassac rivers come together.

The bird lives in a type of habitat called floodplain scrub, which is dense with vegetation. The Wildlife Conservation Society speculates that is what kept it hidden for so long. There is little of its habitat remaining in the city itself, but the bird remains abundant in larger tracts of floodplain scrub outside city limits, including a conservation area. However, it lives only in Cambodia. Only one other known bird species, the Cambodian laughingthrush of the Cardamom Mountains, is found solely in Cambodia.

The scientists recommend that the Cambodian tailorbird be classified as "near threatened" under the International Union for Conservation of Nature's red list — one level below "vulnerable" and two levels below "endangered."