The Mata Mata is a turtle from the Chelidae family originally from South America. It is the only species of the Chelus genre.
Due to its appearance it is a truly strange and unmistakeable turtle: it has a brown or black-ish shell of 45cm in length. The plastron is narrow, markedly shortened at the front and in the male it is concave. The head is triangular, flat and elongated. It has numerous protuberances on the skin. It has two barbels and two additional filaments on the chin. The snout is long and tubiform. The upper jaw is neither curved nor shortened. The neck is flat and quite long, more so than the vertebral column inside the shell, and it has flaps on either side that give it a ridged appearance. Head, neck, feet and tail are brown grey in adults. Each front foot has five claws with webbed membranes. The tails on the males are thicker and longer.
The matamata turtle prefers slow-flowing rivers, calm lakes, swamps and marshes. It lives in tropical forests, to the east of Bolivia, Peru, Ecuador and Colombia, south of Venezuela and Guyana, and to the north and centre of Brazil.