Sumatran pitviper, Trimeresurus sumatranus (Raffles, 1822), Sarawak / Borneo 1100m ASL

Borneo populations of Trimeresurus sumatranus are documented from Kalimantan and the Malaysian states of Sabah and Sarawak; the species is also recorded from Sumatra and parts of Peninsular Malaysia and southern Thailand. It inhabits wet forested environments from sea level to about 1,000 m, and has been reported from habitats including bamboo thickets, mangroves, swamps, plantations, and cultivated fields. The species is chiefly arboreal, typically using low vegetation (bushes, shrubs, lower tree foliage) and is reported as both diurnal and nocturnal; individuals have been observed basking in early morning. Documented prey includes small mammals, frogs and lizards. It is oviparous; a clutch of 17 eggs guarded by a female has been reported.