Hyporthodus nigritus, the Warsaw grouper is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is part of the family Serranidae, which also includes the anthias and sea basses. It is found in the Western Atlantic from Massachusetts to the Gulf of Mexico, Cuba, Trinidad, and south to Brazil (Rio de Janeiro). Its natural habitats are open seas, shallow seas, subtidal aquatic beds, and coral reefs. It is threatened by habitat loss.