Sept. 11, 2012 --
More than 8,000 scientists from the IUCN Species Survival Commission (IUCN SSC) have identified 100 of the most threatened animals, plants and fungi on the planet. Conservationists fear these animals may die out, since none offer humans with obvious benefits. Among those listed is this animal, the red crested tree rat (Santamartamys rufodorsalis). The small rodent was only known from two specimens collected in 1898 from the Santa Marta Mountains in Colombia -- until 2011 when one of the elusive rats shuffled up to two biologists in the field.
Muennink's spiny rat (Tokudaia muenninki) is a rodent in the family Muridae. It is found only in Okinawa Island, Japan. In 2008, the first wild specimen in over 30 years was caught in the northern part of Okinawa island.
Salanoia durrelli, also known as Durrell's vontsira, is a Madagascan mammal found only in the Lac Alaotra area. It is most closely related to the brown-tailed mongoose.
The geometric tortoise (Psammobates geometricus) is a medium-sized terrestrial tortoise that is the rarest of the three tent tortoise species, native to southern Africa. The threatened tortoise is named for the highly geometric pattern on its domed shell.
Archey's frog, Leiopelma archeyi, is a primitive frog native to New Zealand. The frog closely resembles fossilized remains of frogs that lived 150 million years ago.
The Table Mountain ghost frog (Heleophryne rosei ) has highly webbed rear limbs that make it a strong swimmer, but weak jumper. It is found on the slopes of Cape Town's Table Mountain.
The Sumatran rhinoceros (Diceros sumatrensis) is a small rhino that survives in dwindling numbers in the Indonesian and Malaysian rainforests.
The Amsterdam albatross (Diomedea amsterdamensis) is a large albatross which breeds only on Amsterdam Island in the southern Indian Ocean.
Yes, even fungi are threatened with extinction. This fungus, Cryptomyces maximus, appears as shining black blisters with orange/yellow highlights. It is seen, very rarely, throughout Europe.
The Santa Catarina's guinea pig, Cavia intermedia, hails from South America. It is found in Brazil on the small island of Moleques do Sul in the state of Santa Catarina.
The Great Indian bustard (Ardeotis nigriceps) is found in India and adjoining regions of Pakistan. The large bird features long legs giving it an ostrich-like appearance and it's among the heaviest of flying birds. It's estimated that as few as 250 individuals survive today.
The stunning, but critically endangered, Araripe manakin (Antilophia bokermanni) was first discovered as recently as 1996. The bird, which lives in north eastern Brazil, was named Antilophia bokermanni in honor of the Brazilian zoologist and wildlife filmmaker Werner Bokerman, who died in 1995.
PHOTOS: Animals at Risk
One of the most secretive creatures on Earth — the saola — has been photographed in Vietnam for the first time in 15 years.
Scientists first discovered the saola in 1992 in Vietnam near the country's border with Laos. It was the first large mammal new to science in more than 50 years. But since its discovery, the elusive creature has rarely been seen in the wild, earning it the nickname the "Asian unicorn" (even though it has two long horns instead of one).
A lone saola was documented this past September by a camera trap set up in the Central Annamite Mountains by the World Wildlife Fund (WWF) and Vietnamese wildlife officials. [Rare Images of the Saola, One of Earth's Most Elusive Mammals]
"When our team first looked at the photos we couldn't believe our eyes," Van Ngoc Thinh, head of the WWF in Vietnam, said in a statement. "Saola are the holy grail for Southeast Asian conservationists so there was a lot of excitement. This is a breath-taking discovery and renews hope for the recovery of the species."
Though the beast is more closely related to wild cattle, it resembles an antelope with two sharp horns that can reach up to 4 feet (1.2 meters) in length.
The last time a saola was spotted in the wild was 1999, but it hasn't been seen in Vietnam since 1998. In 2010, villagers in the Laos province of Bolikhamxay caught a saola, but the animal died shortly after capture.
WWF conservationists say they are working with Vietnamese partners to protect saolas from illegal hunting.
"Saola are caught in wire snares set by hunters to catch other animals, such as deer and civets, which are largely destined for the lucrative illegal wildlife trade," Van Ngoc said. He added that 30,000 snares have been removed from the saola habitat since 2011 and more than 600 illegal hunters' camps have been destroyed.
"Confirmation of the presence of the saola in this area is a testament to the dedicated and tireless efforts of these forest guards," Van Ngoc said in a statement.
Scientists suspect that no more than a few hundred or a few dozen saola exist in the wild, but they have not been able to come up with a precise population estimate. The species is listed as critically endangered by the International Union for Conservation of Nature.
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