Dozens of animal and plant species ranging from vividly coloured birds to a tree kangaroo thought to be close to extinction, were revealed today by scientists who landed by helicopter in a "Garden of Eden".

The tract of jungle on the slopes of the Foja mountain range in New Guinea’s most remote jungles last November were looking forward to an encounter with an unspoilt tropical forest rich in wildlife.

What they found left them astonished. The team from Conservation International and the Indonesian Institute of Sciences described today a lost world untouched by man, inhabited by dozens of species new to science and endangered mammals so tame that they allowed themselves to be picked up and handled.

The expedition’s findings could prove one of the most spectacular scientific discoveries of recent years. They also reveal the million hectare forest covering the Foja Mountain range in the Indonesian part of New Guinea as the largest surviving pristine tropical forest in the Asia-Pacific region, and probably one of the most biologically rich on earth.

The expedition identified twenty new species of frogs, four new butterflies, five plant species including the world’s biggest rhododendron bloom, a tree kangaroo that was thought to be on the brink of extinction, the first new bird to be discovered in New Guinea for 60 years, and a spectacular‘lost’ bird of paradise that had not been recorded since the nineteenth century.

The forest, much of it at an altitude over 1,600 metres, is so remote that the nearest tribesmen never venture into its trackless depths.

In Jakarta the co-leader of the expedition, Bruce Beehler, said today: "There was not a single trail, no sign of civilization, no sign even of local communities ever having been there.

"It is as close as you can get to the Garden of Eden."

To reach the forest the team of 11 scientists from Indonesia, America and Australia were dropped by helicopter onto a clearing in a peat-bog, for a month-long stay.

One of their finds was a Golden-mantled Tree Kangeroo, which unlike its ground-hopping cousins lives in tree tops. The animal is new to Indonesia. It is believed to have been hunted nearly to extinction in neighbouring Papua New Guinea, where it was discovered in 1993.

They also discovered a previously unknown honeyeater with a bright orange face-patch and a pendant wattle under each eye. If confirmed it would be the first new species of bird to be discovered in Indonesia since the inconspicuous Tanimbar Bush Warbler in 1985, and the first in New Guinea since 1939.

All the findings, including a tiny microhyid frog less than half an inch long, must be published and reviewed by their peers before being officially classified as new species, a process that may take several years.

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