A Khorat big-mouthed frog (left), known by its scientific name Limnonectes megastomias, and a Cat Ba leopard gecko, known by its scientific name Goniurosaurus catbaensis.

A gecko with leopard-like stripes on its body and a fanged frog that eats birds were among 163 new species discovered last year in the Mekong River region of Southeast Asia, an environmental group said on Friday.

WWF International said that in 2008 scientists discovered 100 plants, 28 fish, 18 reptiles, 14 amphibians, two mammals and one bird species in the region. That is in addition to the 1,000 new species catalogued there from 1997 to 2007.

"After millennia in hiding these species are now finally in the spotlight, and there are clearly more waiting to be discovered," said Stuart Chapman, director of the WWF Greater Mekong Program.

Researchers working for WWF warned that the effects of climate change, including an upsurge in droughts and floods, threaten the diverse habitat that supports these species.

"Some species will be able to adapt to climate change, many will not, potentially resulting in massive extinctions," Chapman said in a statement. "Climate change will further shrink their already restricted habitats."

Among the stars in this new list was a fanged frog in eastern Thailand. Given the scientific name Limnonectes megastomias, the frog lies in wait along streams for prey including birds and insects. Scientists believe it uses its fangs during combat with other males.

Another unusual discovery: the leopard gecko found on Cat Ba Island in northern Vietnam. Goniurosaurus catbaensis has large, orange-brown cat-like eyes, and leopard stripes down the length of its body.

Lee Grismer, of La Sierra University in California, said he found the gecko and was "engrossed" in capturing it "when my son pointed out that my hand was on a rock mere inches away from the head of a pit viper."

Other new species found were a tube-nosed bat named Murina harpioloides that lives in southeastern Vietnam and a new bird species called the Nonggang babbler found in the karst rainforest on the Chinese-Vietnamese border, an area of limestone fissures, sinkholes and underground streams.

Experts said a range of factors contributed to the upsurge in new species including better access to regions that have seen decades of war and political unrest and governments stepping up spending on research to protect and identify plants and animals.

The discoveries have been published in peer-reviewed journals and the WWF simply compiled the findings to publicize what it says could otherwise go unnoticed.

The WWF called for efforts to ensure the new species are protected, by preserving their habitat and the river networks that are a foundation of the region's ecosystem.