The saola, also known as the Vu Quang ox or Asian biocorn, is one of the world's rarest mammals. It was discovered in May 1992 in the Vu Quang Nature Reserve by a joint survey of the Ministry of Forestry and the World Wild Fund for Nature. Saola are most easily recognized by their two parallel horns with sharp ends, which can often grow to be up to 20 inches in length. They have striking white markings on the face and large maxillary glands on their muzzle, which are possibly used to mark territory or attract mates. Saola are found exclusively in the Annamite Mountains of Laos and Vietnam.



  • It is thought that in Laos, the saola breeds seasonally between the end of August and the middle of November. Births tend to occur between mid-April and late June, coinciding with the end of the dry season. The timing of the wet and dry seasons is different in Vietnam, so it is possible that the saola's breeding season may be different there.
  • The IUCN Saola Working Group estimates that probably no more than a few hundred saola remain, and possibly as few as a few tens.
  • The IUCN has classified the saola as critically endangered.
  • The saola's scientific name is Psuedoryx nghetinhensis.