Family : GEOEMYDIDAE
Species : Heosemys grandis
Maximum carapace length : 48 cm

The Giant Leaf Terrapin (or 'Giant Asian Pond Turtle') inhabits standing water bodies such as ponds, lakes and slow-flowing pools in freshwater swamp forest.

It prefers shallow water, and spends much time soaking in the margins.  When out of the water it generally remains hidden amongst vegetation, but on occasions may be spotted  basking in the sun on open ground.

The species is mainly herbivorous, but will also feed opportunistically on freshwater invertebrates and fishes.

The carapace is light to medium brown in adults. In younger turtles individual scales are often yellowish brown in the centre and darker brown at the margin. There is a pale vertebral keel in both juveniles and adults.

The head is robust and orange-brown in colour, and the snout is blunt : the sides of the head and neck are mottled.

The posterior marginal scales (i.e. the scales at the edge of the carapace towards the rear of the shell) are serrated, in the same manner as adults of the closely-related Spiny Terrapin.

This relatively large turtle, the carapace of which is up to 48 cm long, is commonly reared in captive or ornamental ponds including those inside Buddhist temples : escapees and introduced populations are thus common.

Native populations of this species occur in Myanmar, Thailand, Cambodia, Vietnam, Laos and parts of northern Peninsular Malaysia. In Singapore the species is introduced, though there are no breeding records in the wild.

Fig 1 : Giant Leaf Terrapin basking in the morning sun at a flooded and degraded freshwater swamp forest at Ulu Sembawang, Singapore.

Fig 2 : Habitat at Ulu Sembawang, Singapore comprising flooded and degraded freshwater swamp forest with numerous treefalls.

Photos thanks to Tony O'Dempsey


References : H12