New findings, published Scientific Reports, have identified that langurs found in Myanmar, Thailand, Malaysia, Singapore, and Indonesia, are actually three distinct species. By studying DNA found in the monkey’s droppings, the researcher were able to identify this taxonomical error in a non-invasive manner. Andie Ang, co-author and research scientist at the Wildlife Reserves Singapore Conservation Fund, pioneered this method of in his work over a decade ago with langurs. Langurs are notoriously difficult to observe—rare, flighty, spending most of their time in treetops. Andie was able to gather genetic information from langur scat.
For two of the newly understood monkey species, the Raffles’ banded langur (Presbytis femoralis) and the East Sumatran banded langur (Presbytis percura), this new discovery of re-classification brings urgent conservation concerns, as they now qualify as critically endangered due to small populations and limited ranges. Ang estimates that the Raffles’ banded langur’s total population hovers around just 300 to 400 individuals. The other langur species, the Robinson’s banded langur (Presbytis robinsoni), on the other hand, is more widespread, and is still classified as “near threatened” by the International Union for Conservation of Nature.