An Atlantic triton (Charonia variegata) attacks a black sea urchin (Arbacia lixula) at the island of Donousa. Atlantic tritons are gastropod mollusks that walk slowly on the seabed looking for food. As soon as they spot an urchin they pull out their mouth that looks like a brown tube. Slowly they turn the urchin upside down and with the radula, a chewing anatomical structure located at the base of their oral cavity, they break the shell from the fragile underside of the urchin. A triton takes about half an hour to catch and devour an urchin. They also prey on starfishes and smaller gastropods, but sea urchins make up 80% of their diet. Unfortunately, although fishing tritons is prohibited by law, many areas are still hunted, resulting in the collapse of their underwater ecosystems. The presence of tritons in an area is a sign of healthy seabed, as these big gastropods control the urchin overpopulation, a sight that we now see in many coastal seabeds of Greece.