Family : COLUBRIDAE
Species : Ptyas fusca
Maximum Size : 3.0 metres

The White-bellied Rat Snake, or 'Brown Rat Snake', inhabits lowland and lower montane forest, to elevations of around 1300 metres. This snake is often found patrolling forest streams: it  preys on aquatic and riparian fauna including frogs, lizards and other small vertebrates.

Its body is elongate and slender, and its tail is extremely long and whip-like. Its head is long and narrow, and distinct from its neck. Its eyes are large, and the pupils are rounded. The base of its tongue is bluish.

When accidentally disturbed it often stays motionless with its neck and anterior part of its body raised: it may also gently move the anterior part of its body from side to side.

Its typical body colour is brown or reddish-brown, although smaller examples may be greenish. In terms of field identification, the colour and patterning in the middle section of its body is diagnostic: a broad black stripe separates the brown dorsum from the pale belly. A broken, vertebral stripe may also be present.

This species occurs in southern Thailand, Peninsular Malaysia, Singapore, Borneo, Sumatra and other parts of Indonesia including the islands of Bangka, Belitung and the Natuna Islands in the South China Sea.

Figs 1 and 2 : Two fully-grown, three-metre, reddish-brown examples from different forest streams in Singapore. The example in Figure 2 remained motionless in this posture for at least 30 minutes.

Figs 3 and 4: Greenish juveniles, of around 60 to 80 cm total length, in swamp forest habitat, Singapore.

Figs 5 and 6 : Large, brown example from Taman Negara, Peninsular Malaysia: it was observed moving swiftly through a resort area, adjacent to lowland forest.

Fig 7 : Example from swampy habitat in Singapore; this snake appears to have a bulge in its neck, suggesting it has just ingested some prey, probably a frog.


References :

Das, I., 2004. Lizards of Borneo - A Pocket Guide. Natural History Publications (Borneo) Sdn. Bhd.
 

	Patterning ...
	Sequential images of a brownish White-bellied Rat Snake moving through leaf litter.
	Anterior part of the body.
	Middle part of the body.
	Posterior part of the body.
	Anterior part of the tail.