Gumbrecht's Green Pit Viper, Dragon Millipede, Huntsman Spider: More than 1000 species discovered in Mekong Delta

Scientists have discovered more than 1,000 species in Southeast Asia's Greater Mekong region in the past decade, including a spider as big as a dinner plate, the World Wildlife Fund said Monday.

A rat thought to have become extinct 11 million years ago and a cyanide-laced, shocking pink millipede were among creatures found in what the group called a "biological treasure trove".

The species were all found in the rainforests and wetlands along the Mekong River, which flows through Cambodia, Laos, Myanmar, Thailand, Vietnam and the southern Chinese province of Yunnan.

"It doesn't get any better than this," Stuart Chapman, director of WWF's Greater Mekong Programme, was quoted as saying in a statement by the group.

The Dragon Millipede "whose shocking-pink exterior would put a 1980s fashionista to shame" is one of the lucky few. The "dragon millipede" (Desmoxytes purpurosea) was first described in 2007 by scientists in Thailand. Researchers suggest the bright colouring acts as a warning to would-be predators, as the millipede has glands that produce cyanide as a defence mechanism.

The "shocking pink" dragon millipede, found by a zoological exploration team in Thailand, was named one of the Top 10 species discovered in 2007 by the International Institute for Species Exploration (IISE) based at Arizona State University. According to a December 2008 report from the World Wildlife Fund, the bright pink dragon millipede is one of more than 1,000 new species discovered or identified between 1997 and 2007 in the Greater Mekong region, which includes parts of Thailand, Vietnam, Cambodia and Laos.

Conservation group WWF says that more than 1,000 species new to science have been recorded in South-East Asia's Greater Mekong region over the past decade. These include 22 snake species, including this green pitviper (Trimeresurus gumprechti).

The Laotian rock rat (Laonastes aenigmamus) was first recorded by scientists at a food market in Laos. Remarkably, researchers say this species is the sole survivor of an ancient group of rodents understood to have died out 11 million years ago.

The Laotian rock rat or kha-nyou (Laonastes aenigmamus), sometimes called the "rat-squirrel", is a rodent species of the Khammouan region of Laos. The species was first described in a 2005 article by Paulina Jenkins and coauthors, who considered the animal to be so distinct from all living rodents that they placed it in a new family, Laonastidae.

In 2006 the classification of the Laotian rock rat was disputed by Mary Dawson and coauthors. Dawson and her colleagues suggested that instead it belongs to the ancient fossil family Diatomyidae, that was thought to be extinct for 11 million years, or since the late Miocene. It would thereby represent a Lazarus taxon. The animals resemble large dark rats with hairy, thick tails like those on a squirrel. Their skulls are very distinctive and have features that separate them from all other living mammals.

Huntsman spider is a common name given to the family Sparassidae (formerly Heteropodidae). The larger specimens of these spiders are sometimes referred to as Wood Spiders, due to their common preference for inhabiting woody places (forest, mine shafts, woodpiles).

These eight-eyed spiders are found in Australia, New Zealand, South Africa, Southeast Asia, the Mediterranean, Florida, and Hawaii, and possibly in many other tropical and semi-tropical regions. They can be found as far north as England, Sweden and Wales .