The François langur[1], also called the white side-burned black langur, François leaf monkey, or Tonkin leaf monkey, is a species of Lutung and the type species of its species group.
- With slender bodies, François’ langurs are acrobatic and agile monkeys. However, their dark, hairy forms look like mere shadows as they climb and descend gray karst cliffs and leap between the trees that jut out from their sheer ledges.
- Slender limbs and long, muscular fingers are their best insurance against a fatal slip and fall down the side of their mountain huts.
- A tail longer than their torso gives them incredible balance. The skin on their face, feet, and hands is as black as their fur.
- Above a gull-shaped brow bone, a tuft of hair rises to a triangular point. Their ears, also colored black, are bordered at the top with glossy white fur that stretches down their cheeks in the form of white sideburns, their most distinctive feature.
- Also, females have a distinctive patch of white fur near their genitals.
