The Mata mata (Chelus fimbriata)

The mata mata's brown or black, oblong carapace can measure up to 95 cm (37 in) at adult age.[13] The full adult weight is 21 kg (46 lb).[13] The mata mata's plastron is reduced, narrowed, hingeless, shortened towards the front, and deeply notched at the rear with narrow bridges.[12] These may be meant to allow the turtle to resemble a piece of bark, camouflaging it from possible predators.[14] The plastron and bridges are cream to yellow or brown.[12] The head, neck, tail, and limbs are grayish brown on adults.[12] The neck is longer than the vertebra under its carapace and is fringed with small skin flaps along both sides.[12] Hatchlings show a pink to reddish tinge in the underside edge of their carapaces and plastrons that gradually disappear as they grow.