There is a remarkable creature living in freshwater ecosystems called the mata mata turtle in the rivers of the Amazon and Orinoco basins that is so thoroughly camouflaged as rotting vegetation that fish swim directly over it without reacting. This remarkable reptile does not chase prey. It does not lunge. Instead, it simply opens its enormous mouth so rapidly that the resulting rush of water sucks the fish in before it has time to register what is happening. The whole strike takes less than a millisecond.
What Makes the Mata Mata Turtle So Unique?
The mata mata turtle’s head is flat, triangular, and covered in flaps and ridges of skin that break up its outline and mimic the texture of decomposing leaves. The shell is rough and algae-covered. The neck is long and fringed with skin filaments that wave gently in the current, resembling waterlogged plant material. Lying motionless on a riverbed, this unusual turtle is genuinely invisible to anything that is not specifically looking for it.
The feeding mechanism is called suction feeding, and the mata mata has taken it further than any other turtle species. The mouth opens so fast and so wide that the pressure differential created is enough to draw in not just the fish but a significant volume of water around it. The turtle then closes its mouth slowly, expelling the water through the sides while retaining the fish, and swallows. It cannot chew—everything goes down whole. For more detailed information about this species’ conservation status and biology, see the IUCN Tortoise & Freshwater Turtle Specialist Group species account.
The mata mata’s eyes are tiny and probably not very useful for hunting. Instead, this turtle finds prey primarily through its lateral line system, which detects the pressure waves produced by fish moving nearby, and through the sensitive skin filaments on its neck. These filaments respond to water movement, allowing the mata mata to hunt effectively by feel in murky water, waiting for something to swim close enough to vacuum up.
Looking at a mata mata turtle, the camouflage is so complete that the animal reads as debris until it moves. Even then, the movement is so slow and deliberate that it takes a moment to register. This unique turtle has been perfecting this particular survival strategy in Amazonian rivers for a very long time, and it is remarkably good at it.
The Breathing Problem
The mata mata turtle cannot raise its head above water easily because of its long neck and flat head shape. Instead, it breathes by extending its long tubular snout to the surface like a snorkel, drawing air without exposing the rest of the body. In shallow water, the mata mata can breathe while remaining almost entirely submerged and motionless—which is exactly what an ambush predator that relies on looking like dead leaves needs to be able to do.