Australo-American Side-Necked Turtles: Chelidae

Physical characteristics: The matamata is one of the larger side-necked turtles as well as one of the biggest freshwater turtles; its dark upper shell can reach up to 18 inches (46 centimeters) in length, and it can grow to a weight of 27 pounds (12 kilograms). It has a flat, lumpy, triangular head, with a rough fringe, or edging. The head sticks out from a flat, knobby shell. Two tiny eyes dot the head. The turtle's upper shell is mostly dark brown. Juveniles have a pinkish-orange lower shell. Often, only the turtle's head is visible in the water, and Rarely seen, the matamata often travels through the water by walking along the bottom and only occasionally takes an awkward swim. (Gail M. Shumwav/Bruce Coleman Inc. Reproduced by permission.) sometimes just its tube-shaped nose breaks the water's surface as the turtle moves about underwater. Females usually are larger than males.

Geographic range: The matamata lives in northern South America.

Habitat: These turtles prefer still or slow-moving freshwater habitats, or areas in which to live, but some are able to live in saltier waters. Although matamatas sometimes live in swift-moving rivers, they stay out of the current and move beneath underwater banks or logs.

Diet: The matamata is mainly a fish-eating species; it ambushes, or attacks, its prey by settling on the bottom and waiting for a fish to approach. Water currents brush the turtle's head fringes back and forth, and many scientists think that this movement attracts fishes. When the prey is close enough, the turtle darts out its head while enlarging its neck and mouth, and sucks in a great gulp of water along with the prey. The turtle then releases the water from its mouth and eats the fish. Some turtle experts believe that the skin flaps, or fringes, on the head may also help the turtle sense water movement and know when prey species are swimming through the murky, or dark, water of muddy ponds.

Behavior and reproduction: Rarely seen, this side-necked turtle often travels through the water by walking along the bottom and only occasionally takes an awkward swim. Juveniles are known to bask, but adults do not. Once a year, the females make nests, sometimes in riverbanks, where they lay eight to twenty-eight round eggs that measure 1.4–1.6 inches (3.6–4 centimeters) in diameter, or width. The eggs hatch more than six months later. Little is known about courtship, mating, or other activities of these turtles in the wild.

Matamatas and people: Matamatas are quite popular in the pet trade, probably because of their unusual fringed heads.

Conservation status: This turtle is not threatened. ∎