The Greater Mekong region of Southeast Asia holds a wealth of biological riches with its natural landscapes and rare wildlife. The six countries (China, Myanmar, Laos, Thailand, Cambodia and Vietnam) that make up the 200 million-acre area are home to "some of the most biologically diverse habitats in the world," according to the World Wildlife Fund (WWF).

Every year, scientists travel to the Mekong River and the land it snakes through to study these ecosystems, and in 2015 they identified 163 new species for the first time, including nine amphibians, 11 fish, 14 reptiles, 126 plants and three mammals.

“The Greater Mekong region is a magnet for the world’s conservation scientists because of the incredible diversity of species that continue to be discovered here. These scientists, the unsung heroes of the planet, know they are racing against time to ensure that these newly discovered species are protected and saved," Jimmy Borah, wildlife program manager for WWF-Greater Mekong, said in a statement.

One of the new species is the Phuket horned tree agamid, a forest-dwelling lizard native to Phuket Island in Southwest Thailand (pictured above). Acanthosaura phuketensis looks fierce with spikes running down its back, but scientists say it dines on insects and is harmless to humans.

Researchers were surprised to find a reptile on Phuket. "The reptile fauna of Phuket has been ignored for many years by biologists because most of the forest cover of the island has been destroyed by human activities,” conservation biologist Olivier Pauwels said in WWF's statement.

In fact, the Mekong region is under siege from multiple directions, not to mention poaching and illegal trade. Development along the river is booming, with dam construction underway in Laos and Thailand, and a road project in Myanmar and Thailand slated to cut through the Dawna Tenasserim Landscape, one of Southeast Asia’s largest forest ecosystems.

Here are more of the rare, small-range new species scientists have found, beautiful reminders that there's still much left to be explored — and protected — on our planet.

'Ziggy Stardust' snake

This rainbow-headed snake is native to Laos and was dubbed the 'Ziggy Stardust' snake after David Bowie's famous alter ego.
This rainbow-headed snake is native to Laos and was dubbed the 'Ziggy Stardust' snake after David Bowie's famous alter ego. (Photo: World Wildlife Fund)

This rainbow-headed snake (Parafimbrios lao) is native to Laos and named after David Bowie's famous alter ego, Ziggy Stardust. It's the 111th snake species identified in the country. According to WWF, not only is it a new species, it's part of a new genus, Parafimbrios.

While the rainbow pattern on its head is the snake's most obvious differentiating characteristic, it also has an unusual number of scale rows and upper teeth.

“The locality of Parafimbrios lao is already undergoing significant changes and destruction,” said Alexandre Teynié, one of the discoverers.

Wooly-headed bat

The wooly-headed bat doesn't have hair just on its head; it also has thick for on its forearms.
The wooly-headed bat doesn't have hair just on its head; it also has thick for on its forearms. (Photo: WWF)

Murina kontumensis is a medium-sized bat found in the Central Highlands of Vietnam. It's known for the thick, wooly hair that grows on its head and arms. According to the WWF, this member of the Murina genus has been found only in the Central Highlands, "tying its fate to that of its home range."

Klingon newt

The unique red markings on the dorsal ridge differentiate the Klingon newt, which is one of only four newt species in Thailand.
The unique red markings on the dorsal ridge differentiate the Klingon newt, which is one of only four newt species in Thailand. (Photo: WWF)

Measuring about 6 to 7 centimeters long, the tiny Tylototriton anguliceps is distinguished by the striking red markings on its dorsal ridge. The "Star Trek"-named amphibian is only the fourth newt species to be found in Thailand.

However, newts are especially sensitive to pesticides because of their porous skin, which is why Dr. Porrawee Pomchote, who led the team that identified the newt, calls pesticide use one of the main threats to this species.

Orange-eyed litter frog

Orange-eyed litter frog
The tiny orange-eyed litter frog is less than 3 centimeters long and lives high up in the trees of Cambodia and Vietnam. (Photo: WWF)

Leptolalax isos is itty bitty at less than 3 centimeters long and distinguishable by its unique markings and toe webbing. It lives in forests in Cambodia and Vietnam that are under threat from logging and agricultural expansion.

Dr. Jodi Rowley said she and her team had to be patient while this little frog was identified as a new species — a process that took 10 years. “While there are certainly moments in the field when you know that you are the first scientist to have ever seen a frog — and that is an amazing feeling — in many cases it’s more a process of investigation, and the reward and species description comes many years down the track,” said Rowley.

Gekko bonkowskii

The Gekko bonkowskii has pale blue spotted skin and was found in a remote mountain area of Laos.
The Gekko bonkowskii has pale blue spotted skin and was found in a remote mountain area of Laos. (Photo: WWF)

The Gekko bonkowskii is another species that forced scientists to be really patient before it could be confirmed as a new find. Because there are many types of geckos in Laos, "sophisticated DNA analysis" was used to differentiate this one from the rest, WWF says.

The pale blue spotted gecko was named for the scientist who made the discovery, Dr. Michael Bonkowski. He described his team's mission to study the mountains of Laos as "operating under harsh conditions in remote terrain, where sometimes their only source of drinking water was found dripping off stalactites in caves."

'The Banana Pride of Nan'

'The Banana Pride of Nan' is a rare banana species found in Northern Thailand. Only two small populations of this plant have been located.
'The Banana Pride of Nan' is a rare banana species found in Northern Thailand. Only two small populations of this plant have been located. (Photo: WWF)

Of the 163 newly discovered species, 126 of them are plants, including Musa nanensis, a rare banana species found in northern Thailand. With its distinctive bright red flower, only two small populations of this plant have ever been found.

“I have been working on the diversity of the banana family (Musaceae) in Thailand for 15 years, and the discovery of the unique structure of this species changed the description of the whole family,” says Dr. Sasivimon Swangpol of Mahidol University in Bangkok.

The species, which is named after the Nan province where it lives, is considered critically endangered due to deforestation, WWF says.

Purple mouse-eared flower

Purple mouse-eared flower
This small purple flower found at the top of Mt. Victoria in Myanmar has petals that resemble mouse ears. (Photo: WWF)

Impatiens kingdon-wardii was found at the top of Mount Victoria, the highest mountain in Myanmar's Chin Hills range. According to WWF, the last time someone documented finding this small purple flower was 1956; that someone was British botanist and explorer Frank Kingdon-Ward, for whom the plant is named.

This flower, which has petals that resemble mouse ears, was found in small populations around the mountain. The species is considered vulnerable.