WASHINGTON — Amid the misty treetops and giant tomato-sized figs in the Andean cloud forests, researchers spotted the animal the first night.
‘‘It sort of bounced around the trees almost like a monkey,’’ zoologist Roland Kays said, ‘‘doing its thing, eating the figs.’’
The small, bushy-tailed, rust-colored, furry mammal they named the olinguito was a rare find — revealed Thursday by Smithsonian scientists as the first new carnivore species found in the Western Hemisphere in 35 years.
Its discovery is a story that goes back a decade to efforts by Smithsonian zoologist Kristofer Helgen to count the number of species of the olingo, a member of the raccoon family. At the Field Museum of Chicago, what he found in a drawer stopped him dead in his tracks.
The reddish-orange pelts he saw were nothing like the skins of the larger, brownish olingos. Searching further, he found the anatomy of the skull was also different — shorter snout, dissimilar teeth.
‘‘I knew at that point it was a new species, but I also knew I needed to be sure,’’ Helgen said. For years, he toiled away to confirm that the olinguito was a new species with thorough investigation and DNA testing. Finally, he called upon Kays, the world’s resident olingo expert, to help him track down an olinguito in its natural habitat. The researchers, with Ecuadorian zoologist Miguel Pinto, set off on a weeks-long field expedition in 2006 to the Andes.
Among the treetops, the team confirmed the existence of four distinct subspecies of olinguito. With its findings, the team in the following years mapped out the animal’s predicted geographic distributions, reorganized the raccoon family tree using DNA sequencing, and peered into every nook and cranny of their bones.
Finally, the team introduced the newly named creature Thursday.
‘‘Getting a new scientific name out there is really fun,’’ Helgen said. ‘‘It’s almost like giving birth.’’
‘‘Olinguito’’ is Spanish for ‘‘little, adorable olingo,’’ he said at a Smithsonian Institution news conference announcing the discovery. The researchers also published their findings online in the journal ZooKeys.
The discovery corrects a long-running case of mistaken identity. For decades, the animals had been observed in the wild, tucked away in museum collections, and even exhibited at zoos — including the National Zoo.
‘‘In some ways, this animal was hiding in plain sight,’’ said Kays, director of the Biodiversity and Earth Observation Lab at the North Carolina Museum of Natural Sciences. Its pelts and bones were found stashed away in dusty museum drawers, either mislabeled or not labeled at all.
One captured olinguito puzzled zookeepers because it refused to breed or mingle with other olingos.
‘‘They thought it was just a fussy olingo, but turns out it was completely the wrong species,’’ Helgen said.
Weighing only two pounds — about as much as a guinea pig — the creature takes the title of smallest member of the raccoon family. It dines on fruits such as figs but also enjoys insects and plant nectar. Although the new animal is in the taxonomic Order Carnivora — a group of mammals that include cats and dogs — it is not carnivorous because it does not primarily eat meat.
Although olinguitos have been spotted in the cloud forests of the northern Andes — in rain forests at elevations of 5,000 to 9,000 feet above sea level — scientists speculate that the animals also might live elsewhere in Central and South America.
Zoologist DeeAnn Reeder, of Bucknell University, cocurator of a scientific database of mammals, finds the olinguito to be an ‘‘extraordinarily beautiful animal’’ and says that to describe a new carnivore in the 21st century is ‘‘special and amazing.’’
‘‘This gets people excited about science and museum work, and about the things you can discover,’’ she said.
With an estimated population of tens of thousands, the olinguito is not considered endangered.