The saola is the critically endangered bovine that is the only species in the genus Pseudoryx.
The saola, Pseudoryx nghetinhensis, is a rare forest-dwelling bovid from the Annamite Range of Vietnam and Laos. Its long, nearly parallel horns helped earn it the nickname “spindlehorn,” while its extreme rarity has inspired the press nickname “Asian unicorn.” Unlike kouprey, gaur, and anoa, the saola occupies its own genus.
The animal was scientifically recognized after unusual skulls and horns were found during a 1992 survey of Vũ Quang National Park in Vietnam. It was formally described in 1993, making it one of the most notable large-mammal discoveries of the modern era. Genetic studies place it within the cattle-and-buffalo tribe Bovini, but as an unusually early-diverging lineage.
The saola is critically endangered, chiefly because wire snares set for other wildlife can kill it. Sightings are exceptionally scarce: the most recent confirmed camera-trap image dates to 2013. The key distinction is taxonomic: Pseudoryx is the genus, while nghetinhensis identifies the single species within it.