Grouper in the context of "Bottom feeder"

Pseudanthias is a genus of colourful reef fishes of the subfamily Anthiinae, part of the family Serranidae, the groupers and sea basses. They are found in the Indo-Pacific. The species belonging to this genus have a diet consisting of zooplankton, and are haremic. Fishes currently included in this genus were earlier part of the genus Anthias. Pseudanthias is the largest anthiine genus

Predatory fish are hypercarnivorous fish that actively prey upon other fish or aquatic animals, with examples including shark, billfish, barracuda, alligator gar, tuna, dolphinfish, walleye, perch and salmon. Some omnivorous fish, such as the red-bellied piranha, can occasionally also be predatory, although they are not strictly regarded as obligately predatory fish.

Populations of large predatory fish in the global oceans were estimated to be about 10% of their pre-industrial levels by 2003, and they are most at risk of extinction; there was a disproportionate level of large predatory fish extinctions during the Cretaceous–Paleogene extinction event 66 million years ago. Creation of marine reserves has been found to restore populations of large predatory fish such as the Serranidae — groupers and sea bass.

A hypercarnivore is an animal that has a diet that is more than 70% meat, either via active predation or by scavenging. The remaining non-meat diet may consist of non-animal foods such as fungi, fruits or other plant material. Some extant examples of hypercarnivorous animals include crocodilians, owls, shrikes, eagles, vultures, felids, some wild canids, polar bear, odontocetid cetaceans (toothed whales), snakes, spiders, scorpions, mantises, marlins, groupers, piranhas and most sharks. Every species in the family Felidae, including the domesticated cat, is a hypercarnivore in its natural state. Additionally, this term is also used in paleobiology to describe taxa of animals which have an increased slicing component of their dentition relative to the grinding component. In domestic settings, e.g. cats may have a diet derived from only plant and synthetic sources using modern processing methods. Feeding farmed animals such as alligators and crocodiles mostly or fully plant-based feed is sometimes done to save costs or as an environmentally friendly alternative. Hypercarnivores are not necessarily apex predators. For example, salmon are exclusively carnivorous, yet they are prey at all stages of life for a variety of organisms.

Many prehistoric mammals of the clade Carnivoramorpha (Carnivora and Miacoidea without Creodonta), along with the early order Creodonta, and some mammals of the even earlier order Cimolesta, were hypercarnivores. The earliest carnivorous mammal is considered to be Cimolestes, which existed during the Late Cretaceous and early Paleogene periods in North America about 66 million years ago. Many theropod dinosaurs such as Tyrannosaurus rex that existed during the late Cretaceous, although not mammals, were obligate carnivores.

Serranidae is a family of marine fish belonging to the order Perciformes. The family used to contain about 450 species in 65 genera, including some of the sea basses and groupers, but taxonomic revisions split out Epinephelinae (groupers), Grammistini (soapfish), and Anthiadinae (anthias); as a consequence, this family is now much less speciose. Representatives of this group live in tropical and subtropical seas worldwide.

Aquatic feeding mechanisms face a special difficulty as compared to feeding on land, because the density of water is about the same as that of the prey, so the prey tends to be pushed away when the mouth is closed. This problem was first identified by Robert McNeill Alexander. As a result, underwater predators, especially bony fish, have evolved a number of specialized feeding mechanisms, such as filter feeding, ram feeding, suction feeding, protrusion, and pivot feeding.

Most underwater predators combine more than one of these basic principles. For example, a typical generalized predator, such as the cod, combines suction with some amount of protrusion and pivot feeding.