Order : PRIMATES
Family : Cercopithecidae
Species : Presbytis siamensis

Head-body length : approx. 50 cm
Tail length : approx. 70 cm
Weight : maximum approx. 6.5 kg

Presbytis siamensis siamensis is slender in build, with greyish or brownish-grey fur which becomes light grey to whitish on the underside and around the cheeks. Juveniles have distinctive spiked fur on top of the head. The eyes are framed by light fur/skin beneath and a line of pale fur at the side. The tail is dark.

Social groups of the species comprise an adult male, several females, juveniles and young. They feed on young leaf shoots, seeds and forest fruits.

P. s. siamensis is common in the extensive sub-montane forests of central Peninsular Malaysia (the range of this subspecies also extends into southern Thailand).

Other subspecies of Presbytis siamensis occur in parts of Indonesia.

Fig 1 : Female P. s. siamensis with infant in lowland mixed primary/secondary forest at Kledang Saiong, Ipoh, Perak, Peninsular Malaysia.

Fig 2 : P. s. siamensis in lower montane forest at Fraser's Hill, Peninsular Malaysia.

Fig 3 : Adult from Ulu Chepor, Perak, Peninsular Malaysia feeding on a fruit of Artocarpus elasticus.

Fig 3 : Adult from Ulu Chepor, Perak, Peninsular Malaysia feeding on a small, unidentified, forest fruit.


References :

Francis, C.M. 2019. A Field Guide to the Mammals of South-east Asia. Second Edition. New Holland. 416 pp.