The graysby (Cephalopholis cruentata) is a species of marine ray-finned fish, a grouper from the subfamily Epinephelinae which is in the family Serranidae which also includes the anthias and sea basses.

The graysby has an oblong-shaped, robust body with a long snout and, when the mouth is closed, a slightly protruding upper jaw and a bony protuberance at the maxilla.

[5] The Graysby is found in the western Atlantic Ocean, the Caribbean Sea and the Gulf of Mexico.

In the Gulf of Mexico, they are found on rocky reef ledge in depths greater than 27 metres (89 ft).

They prefer to remain within a small area of the home range of about 2,120 square metres (0.52 acres), especially during the day.

[6] The graysby was first formally described in 1802 as Sparus cruentatus by the French naturalist Bernard Germain de Lacépède (1756–1825) with the type locality given as the Antilles and Bahamas.