A megalodon is a big shark. It has rough skin and a curved body.
Megalodons are extinct now but they lived 66-56 million years ago. They ruled the sea until the earths sea levels fell.
Megalodons feasted on fish, turtles and mammals like whales. A magalodons tooth is about as big as an adult hand.
Did you know that a megalodon is bigger than a bus!