Malabar grouper, Epinephelus malabaricus

Groupers are Teleosts, typically having a stout body and a large mouth. They are not built for long-distance, fast swimming. They can be quite large, and lengths over a meter and the largest is the Atlantic goliath grouper (Epinephelus itajara) which has been weighed at 399 kilograms (880 pounds) and a length of 2.43 m (7 ft 11+1⁄2 in),though in such a large group, species vary considerably. They swallow prey rather than biting pieces off it. They do not have many teeth on the edges of their jaws, but they have heavy crushing tooth plates inside the pharynx. They habitually eat fish, octopuses, and crustaceans. Some species prefer to ambush their prey, while other species are active predators. Reports of fatal attacks on humans by the largest species, such as the giant grouper (Epinephelus lanceolatus) are unconfirmed.

Their mouths and gills form a powerful vacuum which pulls their prey in from a distance. They also use their mouths to dig into sand to form their shelters under big rocks, jetting it out through their gills.

Research indicates roving coralgroupers (Plectropomus pessuliferus) sometimes cooperate with giant morays in hunting. Groupers are also one of the only animals that eat invasive red lionfish.