Saola, also called "Asian unicorns," were first discovered in 1992. The find was astounding. A large mammal hadn't been discovered since the 1930s.
Although they have two horns, the animals got their nickname because of their secretive ways. They're so mysterious that researchers began to compare them to unicorns.
This female was captured in 1996. The animals don't do well in captivity, and typically die in just days or weeks after capture.
Two decades ago, Vietnamese scientists identified the new species only from strange, horned skulls villagers had collected in the lush forests of the Annamite Mountains along the Vietnam-Laos border.
Scientists have never observed saola in their natural environment, and the secretive creatures have been caught on film in the wild only once, by a camera trap, in 1999. This is one of those images.
A member of a patrol team holds wire snares collected in saola habitat, in central Laos, 2009. Although saola aren't directly targeted, they are often caught in traps meant for other animals, causing devastating declines for a critically endangered species.
A shot of the lush, tropical mountain rainforests saola call home. Many a scientists has searched in vain through these dense forests for a glimpse of the rare mammals.
The female saola captured in 1996. Conservationists warn saola numbers are dwindling. There could be a few hundred left, or as few as just several dozen.