Yunnan snub-nosed monkeys are popular among people because of their humanlike faces with bright red lips.  [Photo provided to China Daily]

The primates are popular among people because of their striking features - humanlike faces with bright red lips.

French missionaries first recorded the species' existence in the 1890s.

Black snub-nosed monkeys, or Yunnan snub-nosed monkeys, were considered extinct in China until a Chinese expedition encountered them in the wild in the 1960s.

Even the most liberal estimate by The Nature Conservancy's primate expert Long Yongcheng puts the population around 3,500. Others project fewer than 2,000.

Most occupy Yunnan's northwest.