The painted terrapin, painted batagur, or saw-jawed turtle (Batagur borneoensis) is a species of freshwater turtle native to the Rainforest of Brunei, Indonesia (Sumatra and Kalimantan), Malaysia, and Thailand. The painted terrapin is critically endangered species according to IUCN, listed in The World's Most 25 Endangered Freshwater Turtles and Tortoises 2011. Harvesting by fishermen to eat, poaching to meet pet and food demand, habitat loss due to land conversion to palm oil, and fish and shrimp farming are major threats.
Painted terrapins inhabit estuaries and the tidal portions of medium to large rivers as well as mangrove swamps and creeks. They may also inhabit other areas that are influenced by tides. Painted terrapins migrate during the mating season. Females nest on sea beaches similar to those used by sea turtles.
Painted terrapins are colorful turtles that exhibit both sexual and seasonal dichromatism. Shell color varies with sex and season. In males, the shell is either green or brown/grey. Three bold, black longitudinal stripes run down the shell along the vertebrals and costal areas. These stripes may be continuous or broken up slightly. Males also have black markings on the marginals of the shell. The head of male painted terrapins is black or grey with a broad, mid-saggital dull orange stripe running between the eyes to the snout. Males also have longer, thicker tails than the females. In females, the shell is typically a drab brown color, and is slightly more domed than the shells of males. Females also have black longitudinal stripes on their shells, which may become obscured with age. The head of the female is brown and becomes more grey in color on the neck and limbs.
During the mating season, both sexes exhibit a change in color. The head of females changes to a reddish color. In males, the change in coloration is more drastic. The shell of males changes to a light gray or a creamy white color. Their black stripes are thus much more visible during the mating season. The head of males turns stark white, and the stripe on their head becomes bright red, edged in black. The coloration of males give them a "painted" appearance, giving the species its common name.
Painted terrapins are primarily herbivorous and feed mainly on mangrove fruits, fallen vegetation, shoots and greenery from riverside plants. River grass is a major food source on the Duncan River. Painted terrapins have been observed eating Berembang fruit thrown down by leaf monkeys into the water. In captivity, they have also responded in a similiar manner to humans that throw food to them in the water. They also occasionally feed on village refuse, especially fruit scraps, when discarded into the water. Certain mollusks and shellfish are also consumed, although the consumption of sea creatures may be accidental.
