Saola: The rare 'Asian unicorn' last seen in 2013 — is it extinct or still alive?

The rare and endangered saola (Pseudoryx nghetinhensis) has not been seen in the wild since 2013. (Image Credit: ©Toon Fey/WWF)

Does the elusive saola still wander the mist-shrouded forests of Vietnam and Laos, or has it silently slipped into extinction? Often called the "Asian unicorn" because of its near-mythical rarity, the saola (Pseudoryx nghetinhensis) is one of the most mysterious animals on Earth. Discovered by scientists only in 1992, it was already endangered at the time—and today, it may be gone for good. The last confirmed sighting in the wild was captured on a camera trap in 2013.

Key Facts About the Saola

Since then, conservationists and researchers have scoured the rugged Annamite Mountains, the saola’s only known habitat, for any sign of the elusive creature—but without success. The terrain is so remote and dense that even confirming extinction is difficult. “Right now, the existence of live saolas can neither be proven nor disproven,” says Nguyen Quoc Dung from Vietnam’s Forest Inventory and Planning Institute. “But there are still some signs and indications that give us hope.”

This lingering hope has driven new scientific efforts, including a landmark study recently published in the journal Cell. For the first time ever, researchers from Vietnam, Denmark, and other countries have mapped the entire genome of the saola. By analyzing remains collected from hunters' homes, they were able to generate complete genomes for 26 individuals. The study not only uncovers the saola’s evolutionary past but also explores its potential for survival—if it still exists.

Two Populations, One Future?

The study revealed something unexpected: the saola is divided into two genetically distinct populations, which split between 5,000 and 20,000 years ago. Both groups have been in long-term decline since the Ice Age, and their numbers likely never exceeded 5,000 in the past 10,000 years. However, because each population has lost different types of genetic diversity, combining them could potentially restore some of what’s been lost.

“If we can bring together at least a dozen saolas – ideally a mix from both populations – to form the foundation of a future population, our models show the species would have a decent chance of long-term survival,” says Rasmus Heller, senior author of the study and Associate Professor at the University of Copenhagen. But that scenario depends on one big condition: finding the saola.

Can Genetic Tools Help Us Find It?

Finding even a single individual has proven incredibly challenging. However, the newly sequenced genome offers fresh hope. Scientists can now use advanced methods like environmental DNA (eDNA) analysis with far greater precision. By comparing genetic traces found in water, soil, or even leeches, they may be able to detect the presence of saolas more reliably.

“Now that we know the complete saola genome, we have a much larger toolkit for detecting DNA fragments,” says Minh Duc Le of Vietnam National University, a co-author of the study.

Even in the worst-case scenario—that the saola is already extinct—the research could prove valuable in the future. The data could potentially support efforts in genetic de-extinction, a controversial field that aims to revive lost species.

Still, researchers remain cautious. “Scientists have been searching for saolas since the 1990s,” says Heller. “It’s only gotten harder since then, because there were more of them back then. I’m not overly optimistic, but I really hope the saola is still out there.”