Banded leaf monkey (Presbytis femoralis) The banded leaf monkey Presbytis femoralis inhabits primary forest, mature secondary forest or swamp forest. It is active by day, particularly in the morning and late afternoon, and is mainly arboreal (though in some parts of Thailand the species is known to descend to the ground). Its diet includes new leaves, and forest fruits.
This species is generally shy in nature: males will quickly alert their troupe to the presence of any threat, including the presence of humans, with a loud repetitive ''chi-chi-chi' call, and the troupe will quickly move away to a quieter area. Troupes generally number up to 5 or 6 individuals, and adult males may be solitary.
Their dorsal fur is dark grey-brown to blackish, and the underside is paler. The face is darker than most other species of leaf monkey, though the upper and lower lips are generally pale. The inner part of the thigh is white. Infants can be locally white or beige in colour.
The species has a disjunct distribution and three subspecies are now recognized: Presbytis femoralis femoralis occurs in southern Peninsular Malaysia (Johor) and Singapore, Presbytis femoralis robinsoni occurs in southern Thailand and northern Peninsular Malaysia, and Presbytis femoralis percura occurs in parts of eastern Sumatra.
The Singapore population of Presbytis femoralis femoralis is considered to be highly endangered: based on studies in early 2010 it is estimated there are only around 40 to 60 individuals surviving.