Purple-faced langurs (Semnopithecus vetulus), also known as purple-faced leaf monkeys, are endemic to Sri Lanka. In Sinhala, one of the official languages of Sri Lanka, they are known as “the black monkey of Sri Lanka.” Located near the southern tip of India, the tropical island of Sri Lanka is teeming in biodiversity. This is thanks in part to its varying landscapes and climates. The perimeter is dusted with sandy beaches and the valleys and rivers of the plains make up a large portion of the island. In the south-central area lies the highlands, also known as the wet zone, with its mountain ridges and tall rainforests—this is where purple-faced langurs call home.

Purple-faced langurs live in the lush high canopies of a variety of forests including tropical rainforests, evergreen rainforests, semi-deciduous forests and montane forests. Their range includes the Sinharaja Forest Reserve, the small town of Kitulgala, Galle and Horton Plains National Park. While they prefer life in the tops of the trees, deforestation and other threats have forced groups to survive in more urbanized and farmed areas where they live wherever they can find shelter and cover such as in home gardens or rubber plantations.