Nycticebus kayan is a species of slow loris and a primate that can be found in northern and central areas of Borneo. Its range extends into East Kalimantan and Malaysia. This species prefers to reside in highland areas and it was named after a river that extends through its range known as the Kayan River. It was once classified with the Bornean slow loris, but studies conducted in 2013, focusing on physical differences, showed that it should be classified as a distinct species.
Nycticebus kayan is thought to reach an average body length of 10.8 inches and a weight of .9 pounds. This species has fluffy fur that differs from the Bornean slow loris on the head and face. The dark fur around the eyes can come to a point or be rounded and the stripe that occurs between the eyes can be rounded, like a bulb. The dark and light fur that creates a mask shape on the face of this species contrasts greatly compared to the Bornean slow loris.
As is typical to slow loris species, Nycticebus kayan is arboreal and is active during the nighttime hours. This species consumes plant materials like fruits, nectar, and gums, but it will also consume insects. It is thought that its face markings help it to identify breeding individuals or deter predators. This species, like other lorises, will rub a toxic chemical produced from a gland near its elbow on its fur, which also deters predators. It may lick this gland and bite a predator, which delivers the toxin at a more dangerous level.
Because it was separated from the Bornean slow loris, which holds a conservation status of “Vulnerable,” Nycticebus kayan is thought to be in danger of extinction. Although it has not been evaluated by the IUCN, it would most likely receive a conservation status of “Vulnerable,” unless it was found to be at greater risk. The main threats to all loris species include habitat loss and capture for the illegal wildlife trade, but they are all protected under Appendix I of CITES.
Image Caption: Slow Loris (Nycticebus kayan) in Sabah, Borneo. Credit: Jmiksanek/Wikipedia (CC BY-SA 3.0)