Siebenrockiella crassicollis, is commonly named the Borneo
Black Leaf Turtle, Smiling Terrapin, Black Terrapin,
Malaysian Black Mud Turtle, and Black Mud Turtle, and is
found throughout most of the Asian rainforest in Malaysia,
Myanmar, Sumatra, Borneo, Vietnam, Java, Lower Burma and
Thailand, in shallow, warm, soft-bottomed waters such as
naturally formed ponds and ditches, but is so secretive that
it is rarely seen in the wild.
It stays half-buried in the soft muddy pool bottom most of
the time, but does swim in the deeper areas and come out of
the water to bask at times. When captured and frightened, it
may produce a very bad musk stench.
As its name of Black Leaf Turtle indicates, this turtle is
mostly olive-black: shell, head, legs and tail, but with
some white markings on the head, a white or yellow spot
behind each eye, and white outlining the eyes of females and
the young. The plastron is either all black or brown with
black blotches. As with other Leaf Turtles, the back scutes
form serrations that are leaf-like, and its carapace has at
least a center keel if not three.
The common name Smiling Terrapin comes from its beak shape,
which makes the turtle's face look as though it were
perpetually smiling. Its full growth size is around eight
inches long, and its feet are fully webbed. Males have the
common concave plastron and longer, thicker tails than
females, and they lose the white eye rings at breeding
In the wild the Smiling Terrapin is primarily carnivorous,
and it has wide head and strong jaws, crunching snails and
other mollusks, and even bones from carrion. It also eats
shrimp, small frogs and fish, worms, insects, and probably
wild fruit that falls into the water from the profuse
overhead vegetation in its habitat.
These active and inquisitive turtles, in captivity, have
been seen to enjoy commercial floating turtle foods, worms,
snails, crickets, and other live foods, as well as some
aquatic plants. The hatchlings will eat bloodworms, small
fish such as guppies and crushed commercial food. Be sure to
also provide a good reptile calcium and vitamin D3
supplement for proper bone and shell growth. Black Leaf
Turtles prefer to eat in or near the water, so if kept
indoors using a separate feeding tank is recommended in
order to help keep the main tank clean.
As with all turtles, the best habitat in captivity is an
outdoor pool and land area inside a predator-repelling
enclosure. This turtle is not aggressive, and you can keep a
group of five or so together in a stock tank or wading pool
with a water depth of eight to ten inches. A substrate of
clean river sand will give them something to nose around in.
But as these are tropical rainforest animals, if the
temperature outdoors drops below 55 degrees F. you will need
to move them indoors.
For indoor care, one turtle will need at least a thirty
gallon aquarium; five or six will need at least a seventy-
five gallon. The water in the aquarium should be deep enough
that the turtle can right itself if it is upset, and it must
be well filtered and changed often, with hiding places to
help prevent stress, and kept to 75 to 82 degrees
Fahrenheit. Aquatic plants add hiding places, help with
water quality, and provide handy snacks for adult turtles.
Prepare a dry "land" area with a smooth ramp so they can
escape the water when they wish, and hang a 100 watt
spotlight over a shallow water spot for basking. Keep the
tank at least partially covered for humidity, and run a
full-spectrum UV lamp at least 8 hours per day, so the
turtle can metabolize its calcium and vitamin D3.
If your Borneo Black Leaf Turtle was imported, take it to a
good reptile veterinarian immediately after you buy it, as
imported turtles, especially Asian Turtles, often have
stress and parasite related illnesses.