A skydiving gecko and a fish that mates head-to-head are among hundreds of new species found by scientists in the Greater Mekong region.
Other discoveries in the South East Asian region in 2012-2013 include a new species of giant flying squirrel, an eyeless cave-dwelling spider and a green flying frog which glides between treetops using large webbed hands and feet.
They are among 367 new species documented in a report by conservation charity WWF, Mysterious Mekong, published on World Environment Day to highlight the diverse wildlife in the region.
The news species include 290 plants, 24 fish, 21 amphibians, 28 reptiles, three mammals and one bird.
Dr Thomas Gray, manager of WWF-Greater Mekong's species programme, said: "The species discoveries affirm the Greater Mekong as one of the world's richest and most biodiverse regions.
"If we're to prevent these new species disappearing into extinction, and to keep alive the hope of finding other fascinating creatures in years to come, it's critical that governments invest in conservation and green growth strategies."
The new species of parachute gecko, a camouflage-patterned lizard which extends flaps of skin on its flanks and between its toes to glide from branch to tree trunk, was found in mountainous forest in western Thailand's Kaeng Krachan National Park.
The discovery of the new species of flying squirrel, the Laotian giant flying squirrel which has distinctive red and white fur, is based on a single animal collected from a bush meat market in Laos.
A new species of warbler was found hiding in plain sight in Cambodia's capital Phnom Penh. The Cambodian tailorbird was first seen in 2009 during avian flu tests, and was later formally identified as a new species.
In a cave in Laos a new huntsman spider was discovered, the first of its kind in the world to be found with no eyes, a feature it is thought to have lost as a result of living permanently in darkness.
In Vietnam scientists have identified a new bat, the Griffin's leaf-nosed bat, with a strange fleshy-looking nose that helps it with the echolocation it uses to navigate, and a tiny fish whose sex organs are just behind its mouth so it mates head-to-head.
A huge green frog, Helen's Flying Flog, which grows to up to 4in (10cm) in length, lives in the treetops and only comes down to breed in rain pools, was discovered less than 60 miles (97km) from Ho Chi Minh City.
It was found in a patch of forest surrounded by agricultural land, highlighting the need for conservation in lowland forests, one of the most threatened habitats in the world, WWF said.