The Mata mata, Chelus fimbriatus, is a turtle native to South America. Once one has seen a mata mata, it is unlikely to ever be confused with any other turtle. It is truly a one-of-a-kind species. The name mata mata is derived and translated from the Spanish term “it kills, it kills”.
The carapace is oblong and black or brown, and is about 17.5 inches long. The head is very distinctive, triangular, large, extremely flattened. There are numerous tubercles and flaps of skin. The snout is long and tubular. The upper jaw is neither hooked nor notched. Head, neck, tail, and limbs are grayish brown on adults. The neck is very long, longer than the vertebra under the carapace, and is fringed with small skin flaps along both sides. Each forefoot has five webbed claws.
It prefers slow moving, backwater streams, stagnant pools, marshes, and swamps. Ranges into northern Bolivia, eastern Peru, Ecuador, eastern Colombia, Venezuela, the Guianas, and northern and central Brazil. Prefers shallow water where it can reach the surface to breathe. It can hold its breath for a long time, remaining motionless on the bottom. It creeps along the bottom rather than swim, probably never basks.
A wait and ambush predator, it will remain almost motionless underwater, its bizarre skin flaps helping it to blend into the surrounding vegetation, until a fish comes close. The turtle thrusts out its head and opens its large mouth as wide as possible, creating a low pressure volume that sucks the prey into the turtle’s mouth. The Mata mata snaps its mouth shut, the water is slowly expelled, and the fish is swallowed whole. The prey has to be appropriately sized for the turtle; Mata matas cannot chew very well due to the way their mouths are constructed.