Seeking orangutans and leopards, a team of Indonesian researchers instead discovered Miller's Grizzled Langur, one of the world's rarest primates.

Ethical Expeditions / AP Newly "rediscovered" Miller's Grizzled Langurs sit on a tree branch in Wehea forest in eastern Borneo, Indonesia.

Scientists working deep in the jungle of Indonesia have proven that, sometimes, the best discoveries happen by accident.

Hoping to capture images of orangutans and leopards, the team set up cameras in the Wehea Forest on the eastern tip of Borneo island in June, the Associated Press reported. But upon viewing the photos, the researchers were shocked to see extremely rare Miller’s Grizzled Langurs, which until now have never been photographed. Given the lack of preexisting images, the scientists initially struggled to confirm their startling discovery, but soon enough, the answer was clear.

The creature once inhabited northeastern Borneo, along with the islands of Sumatra and Java and the Thai-Malay peninsula, the AP reported. But a 2005 field survey yielded no trace of the rare primate, and after years of damage from fires, agriculture and mining, Miller’s Grizzled Langurs were presumed extinct.

Although the primates appear in several thousand of the recent images, the researchers have yet to determine how many individual langurs have actually been discovered. The next step? Sort through the photos, return to the forest, and begin counting monkeys.

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