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The saola, Vu Quang ox or Asian unicorn, also, infrequently, Vu Quang bovid (Pseudoryx nghetinhensis), is one of the world's rarest mammals, a forest-dwelling bovine found only in the Annamite Range of Vietnam and Laos. Cousin to the cow, goat, and antelope, the species was defined following a discovery of remains in 1992 in Vũ Quang Nature Reserve by a joint survey of the Ministry of Forestry and the World Wide Fund for Nature. The team found three skulls with unusual long straight horns kept in hunters' houses. In their article, the team proposed "a three month survey to observe the living animal" but, more than 20 years later, there was still no reported sighting of a saola in the wild by a scientist. However, a living saola was photographed in the wild in September 2013 by a camera trap set by the World Wide Fund for Nature and the Vietnamese government’s Forest Protection Department. Van Ngoc Thinh, the WWF's Vietnam country director, said, "This is a breathtaking discovery and renews hope for the recovery of the species."
In late August 2010, a saola was captured by villagers in Laos but died in captivity before government conservationists could arrange for it to be released back into the wild. The carcass is being studied with the hope that it will advance scientific understanding of the saola. Sometimes these animals get caught in snares that have been set to catch animals such as wild boar, sambar and muntjac deer that come to feed on the crops that the farmers have planted. This has become a problem especially with the illegal fur trade for medicines, restaurants and food markets. More than 26,651 snares have been removed from habitats that the Saola has lived in for years.
Habitat and distribution
The Saola inhabits the Annamite Range's moist forests and the Eastern Indochina dry and monsoon forests. They have been spotted in steep river valleys at about 300 to 1800 m above sea level. These regions are distant from human settlements, covered primarily in evergreen or mixed evergreen and deciduous woodlands. The species seems to prefer edge zones of the forests.
Saola stay in mountain forests during the wet seasons, when water in streams and rivers is abundant, and move down to the lowlands in winter. They are shy and never enter cultivated fields or come close to villages. To date, all known captive saola have died, leading to the belief that this species cannot live in captivity.
The saola belongs to the family Bovidae and genetic analysis places it in the tribe Bovini; in other words its closest relatives are cattle, true buffaloes, and bison. However its simple horns and teeth and some other morphological features are typical of less-derived or 'primitive' bovids. Saola are antelopes, in the sense that an antelope is any bovid that is not a cow, sheep, buffalo, bison, or goat. It is not known how many individuals exist, as only 11 have been recorded alive.
An adult saola stands at about 80–90 cm at the shoulder with its entire body length measuring approximately 150 cm (the tail measures additionally out to about 25 cm) and weighs at approximately 90–100 kg. Their hair is straight, short, and surprisingly soft for an animal partly adapted to a montane habitat and is usually of a medium chocolate brown color (though some have been noted to contain variations of a reddish tone). However, this isn't uniform with both the neck and belly a slightly paler shade as well as various white markings scattered across its body, such as white patches on the feet, vertical stripes across the cheeks, and splotches on the nose and chin. There is also a medial black dorsal strip that extends from between the shoulders down and back to fade out into the top of the tail. The tail itself is tricolored and splits evenly into 3 horizontal bands of medium brown, cream, and black, with the cream blending into the white band that extends across its rear. They bear round pupils with dark brown irises and bear a cluster of white whiskers about 2 cm long that protrude from the end of the chin with a presumably tactile function. They also possess a long tongue that can extend up to about 16 cm with its upper surface covered in fine, rearward pointing barbs, presumably to aid in its eating habits.
All saola also possess a pair of slightly diverging horns that closely resemble the parallel wooden posts that are commonly used to support a spinning wheel (which is also the source of their namesake). They are generally dark-brown or black and can measure from about 35–50 cm long; twice the length of their head. These traits are determined not to be exclusive to one sex, with both the horns of the males and females bearing little to no significant variations. The skin is 1–2 mm thick over most of the body, but the skin thickens near the nape of the neck, and at the upper shoulders it thickens to 5mm. This unique adaptation protects them against both predators and rivals' horns during fights.
Local populations report having seen saola traveling in groups of two or three, rarely more.
They possess a pair of highly-developed maxillary glands on either side of the snout, each comprising a rectangular shallow depression of about 1.5 cm deep along the upper muzzle. The depression is covered by sparse flattened hair with rows of pores scattered throughout. The entirety of each gland is covered by a muscular flap that can raise up to about 3 cm to expose scent glands used in marking territory. They then subsequently rub the underside against objects leaving a musky, pungent paste. The saolas' colossal scent glands are thought to be the largest of any living mammal.
Behavior & reproduction
They walk with a gentle, quiet, slow nature. When they sleep, they have their forelegs tucked under their bodies, necks extended, and the chin resting on the floor. It is reported by villagers that saolas are active in the mornings, afternoons, and nights, but not when the sun is overhead.
They are calm in the presence of humans, letting humans pet them and eat out of their hands. On the other hand, they have an intense fear of dogs. When they feel threatened, they contract defensive positions which involve the snorting and thrusting of their head forward exposing their long, straight horns. Their ears are pointed up and straight back with an arched back and a stiff posture. Occasionally they will secrete the paste from their maxillary glands as a defensive reaction which is usually and most commonly observed with dogs. Saolas vocalize themselves with bleats.
In order to mark their territory, saolas open a fleshy flap located over the maxillary glands on either side of the snout and rub it over a rock or place of territory leaving a strong musky paste. Saolas are known to have one of the largest glands of all mammals. In order to defecate and urinate, saolas drop their hind legs and lowering the lower body, urinating and defecating separately, which is not new for bovid species (as saolas are classified).
Saolas spend a significant amount of time grooming themselves. They lick their face and eyes most often and lead into their shoulders and forelegs. They frequently lick their muzzle to disperse flies, as well.
There is very little information about the reproduction cycle and pregnancy cycle; however, the litter size is one. There was one female saola held captive that died pregnant with a male saola which was well formed and had features that were apparent. For lack of information and proper resources, scientists estimate the gestation period as similar to that of Tragelaphi; that is, about 234 days.
They are reported to eat small leafy plants—especially fig leaves, and stems along rivers. While little is known about the full range of their diet, instances of captivity have observed the Saola generally subsisting on a diet of leafy plants such as a species of fern of the Asplenium genus (also known as Spleenwort), broad dark-green plants of the Homalomena genus (Araceae family), and various species of broad-leaved shrubs or trees of the Sterculiaceae family. They have shown to have a greater preference for the unidentified plant of the Sterculiaceae family/Sterculia genus. Seldom have they been reported eating during periods of darkness, most likely due to their diurnal nature. The animal seems to have a browsing diet, considering its small incisors.
The name "saola" has been translated as spindle[-horned] although the precise meaning is actually 'spinning-wheel post horn'. The name comes from a Tai language of Vietnam but the meaning is the same in the Lao language. The specific name nghetinhensis refers to the two Vietnamese provinces of Nghệ An and Hà Tĩnh while Pseudoryx acknowledges the animal's similarities with the Arabian or African oryx. Hmong people in Lao refer to this beast as saht-supahp, a term derived from Lao meaning "the polite animal", because it moves quietly through the forest. Other names used by minority groups in the Saola's range are 'lagiang' (Van Kieu), 'a ngao' (Ta Oi) and 'xoong xor' (Katu)  In the press, Saola have been referred to as Asian unicorns. The appellation is apparently due to the saola's rarity and apparently gentle nature and perhaps because both the saola and the oryx have been linked with the unicorn. There is no known link with the mythical beast; nor with the 'Chinese unicorn', the qilin.
Aside from a long gestation period, the Saola has been an easy target for hunters due to its docile nature. Additionally, the Saola is occasionally caught by snares set by villagers for wild boar. Feral and domestic dogs present another threat, as the ecology of the area historically has not included a canine predator. There are several instances where the villagers hang the horns of the Saola as a symbol of honor. Such trophy hunting deeply endangers the stability of the species as a whole because they have very little defense and can be overpowered quite easily. There is little money available to fund the awareness of the endangerment of this species, let alone the conservation of it, so the trophy hunting continues with no regulation.
A large threat to the saola species is also habitat fragmentation. Due to their shy nature and preference for undisturbed forests, the habitable region for the Saola continues to shrink. They are restricted to high mountain areas where perhaps a few dozen to a few hundred animals remain.
Back in 1992 the bovid known as the Saola was discovered within the restricted mountainous region that separates Vietnam and Laos. There are reported to be only a few hundred of them in the wild. The horn cores of the adult saola are exceptionally long and the genetic name Pseudoryx refers to the superficial resemblance of the Oryx (tribe Hippotragini). As compared to other bovid genera, Pseudoryx differs significantly from all described in appearance and morphology. Bovidae is composed of two major subfamilial clades. This is based on molecular investigations composed on ribosomal mitochondrial sequences of a large taxa sample. The first clade corresponds to Bovidae and assembles members of the tribes Bovini (cattle and buffaloes), Tragelaphini (african spiralled-horned bovids) and Bosalaphini. The second clusters all other bovids, which is composed of Caprini (goats, and muskox), Hippotragini (horse-like antelopes), and Antilopini (gazelles). According to research it has been shown that phylogenetic information for deciphering Bovidae evolution can be found in mitochondrial and nuclear sequences.
The Saola Working Group was formed by the IUCN Species Survival Commission's Asian Wild Cattle Specialist Group, in 2006 to protect the saolas (Pseudoryx nghetinhensis) and their habitat. The Saola Working Group is a coalition that includes about 40 experts from the forestry departments of Laos and Vietnam, Vietnam's Institute of Ecology and Biological Resources, Vinh University, biologists and conservationists from Wildlife Conservation Society and the World Wide Fund for Nature.
Due to the classification of the Saola being critically endangered, a group of Vietnamese scientists from the Vietnam Academy of Science and Technology in central Hanoi, within the Institute of Biotechnology, have looked into a last resort effort of conserving the species by means of cloning. This can prove to be quite difficult due to the fact that cloning even the most well known mammal can be difficult. It would be even more so with a mammal that researchers know little to nothing about, such as the saola.
Other rarely seen big mammals of the Indochina peninsula, also discovered in the 1990s:
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