grouper, common name for a large carnivorous member of the family Serranidae (sea bass family), abundant in tropical and subtropical seas and highly valued as food fish. There are several genera, notably Epinephelus and Mycteroperca, including some 100 species, most of which are characterized by bright markings that change in color and pattern to match the background. In the West Indies and the Florida Keys are found the yellowfin grouper, noted for its many beautiful color phases; the coney, the smallest (9 in./22.5 cm) grouper, colored a livid reddish gray with blue spots; and the Nassau grouper, the rock hind, and the gag. The largest of the sea bass are the groupers called jewfishes—the black jewfish, or Warsaw grouper, Hemichromis bimaculatus, reaches a length of 6 ft (183 cm) and a weight of 500 lb (225 kg) and the spotted jewfish is even larger (up to 600 lb/270 kg). The red grouper and the black grouper, common N to the Carolinas, form the bulk of the commercial catch; both species weigh up to 50 lb (22.5 kg). Groupers are classified in the phylum Chordata, subphylum Vertebrata, class Osteichthyes, order Perciformes, family Serranidae.

Any of numerous species of fishes (family Serranidae) widely distributed in warm seas, especially members of the genera Epinephelus and Mycteroperca. Groupers are characteristically large-mouthed, heavy-bodied fishes. Some species grow larger than 6 ft (about 2 m) long and heavier than 500 lb (225 kg). Groupers are usually dull green or brown; some species can change their colour pattern, and deepwater individuals may be much redder than nearshore ones. They are prime food fishes, though a few species carry a toxic substance in their flesh and can cause poisoning when consumed, and they provide sport for anglers and spearfishermen. Seealso jewfish; sea bass.

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