Pagai Island macaque a result, the water levels in the forest rivers fluctuate to a much greater degree than before. The alternating flooding and low water levels has also caused an increase in the population of malarial mosquitoes. Pagai Island macaque The Pagai Island macaque ("Macaca pagensis"), also known as the Pagai macaque or Bokkoi, is an Old World monkey endemic to the Mentawai Islands off the west coast of Sumatra. It is listed as critically endangered on the IUCN Red List due to its ever-shrinking habitat. "Macaca pagensis" formerly included the overall darker Siberut macaque as a subspecies, but this arrangement is
White-cheeked macaque the animals caught on tape (including more prominent whiskers, thicker neck hair, and differences in the shape of the genitalia), primatologists in China declared them to be a new species. Their research, along with a series of photographs of the species, was published in the July 2015 issue of the "American Journal of Primatology". In April 2016, a group of wildlife photographers and biologists spotted and photographed the white-cheeked macaque in Arunachal Pradesh, India. Prior to this sighting, the species was thought to exist only in Tibet. Physiologically, the white-cheeked macaque is similar to the other members of the genus