© Chey Koulang

The Southeast Asian Softshell Turtle, Amyda cartilaginea (Family Trionychidae), also known as Asiatic Softshell Turtle or Black-rayed Soft-shelled Turtle is generally found in all the nations of Southeast Asia, except for the Philippines (Vaught, 2015).

It is a large species with a total carapace length up to 850 mm, showing considerable variation in coloration over its wide range in Southeast Asia (Auliya et al., 2016). The carapace of a young turtle can be grayish-brown or black and sometimes with an olive tint. The colour can be uniform or dotted with yellow or black spots, broad radiating streaks, or star-shaped marks, arranged over the midline and extending laterally (Auliya et al., 2016). However, their plastron is white, pale grey, or pale olive, and may show cloudy dark areas. Usually, their heads will have some yellow spots dorsally and laterally that are reduced posteriorly. For the adult, the spotting on the carapace disappears entirely while some large black marks still remain but it becomes less distinct (Auliya et al., 2016).

Southeast Asian Softshell Turtle has a trait that helps differentiate themselves from other similar species which is its noticeably elongated snout (Vaught, 2015). The elongated snout aids the turtle in breathing when it has submerged in water for extended periods of time. This adaptation is known as “pharyngeal breathing” (Vaught, 2015). It normally lives in freshwater with depths ranging from 1 to 12 m. This turtle is most likely to be found in East and West Malaysia. Hunters and fishermen in Malaysia have trapped this softshell turtle in lakes, slow-moving rivers, and fast-flowing rivers near the waterfalls (Vaught, 2015).

The mating season of the Southeast Asian Softshell Turtle takes place from April to September. However, this may vary based on the specific geographic location of each turtle (Ernst, 1996). Generally, the males reach sexual maturity between 4-5 years old while the females take between 8-10 years old (Vaught, 2015). On average, females lay 3-4 clutches in a year and consequently build up to 3-4 nests in one season. Each clutch comprises a minimum of 1 offspring and a maximum of 30. The incubation period for the eggs is approximately between 60-135 days (Auliya et al., 2016).

Southeast Asian Softshell Turtle has adaptations for fast-swimming and for hiding in sediment. Although this turtle spends most of its time in the water, it will also emerge onto land occasionally at night. It can bury itself in the silty sediment easily because it does not have preneural or dermal bones that run along the vertebrae in the front carapace (Vaught, 2015). It will dive headfirst into the sediment, and use its limbs to kick up the sediment until it is covered completely except for its snout (Vaught, 2015). This behavior had caused the tracking and capturing work of researchers to become more difficult as researchers might accidentally step on it before finding its snout protruding from the sediment.

The Southeast Asian Softshell Turtle plays an important role in limiting the growth of the populations of its prey. This turtle is known for its carnivorous diet and nocturnal hunting patterns. It is a predator that likes to ambush its prey which mainly consists of fish, amphibians, insects, and some crustaceans (Vaught, 2015). The egg of Southeast Asian Softshell Turtle is a good source of food for other predators such as monitor lizards, crows, snakes, eagles, wild pigs, and humans. For adults turtles, the natural predators include smooth otters and tigers (Auliya et al., 2016). Besides the role of predator and prey, the Southeast Asian Softshell Turtle is sometimes a scavenger. According to Vaught (2015), there are algae and berries found in the turtle’s feces. Auliya et al. (2016) stated that this turtle is probably an omnivore as plant material was also observed in its stomach contents and fecal matter.

Turtle oils from the carapace of most species have been used worldwide for treating minor ailments, and dermatological purposes related to preventing aging of the skin. Though these market benefits pale in comparison to the market for consumption, they still exist as a small positive market stimulation (Asian Turtle Trade Working Group, 2000; Jensen and Das, 2008a; Kuchling, 2009). Other than that, habitat destruction due to human activities is also one of the major threats to its survival (Auliya et al., 2016). Currently, it is listed as “Vulnerable” under the IUCN Red List (Asian Turtle Trade Working Group, 2000). In Malaysia, it is a listed as "Protected" under the Wildlife Conservation Act 2010.