Gag grouper
(Mycteroperca microlepis)

Mycteroperca microlepis, the gag, gag grouper, velvet rockfish or charcoal belly, 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 comes from warmer parts of the West Atlantic, including the Caribbean and Gulf of Mexico. It is a drab, mottled-gray fish lacking the distinguishing features of most other groupers. Its pattern of markings resemble the box-shaped spots of the black grouper (Mycteroperca bonaci). It lacks the streamer-points on the tail fin that scamp (M. phenax) and yellowmouth grouper (M. interstitialis) have, and lacks yellow coloration around the mouth.

Description
Mycteroperca microlepis has an oblong, robust body that is laterally compressed. The depth of the body is normally less than the length of the head and it is usually roughly equal in depth at the origin of the dorsal fin and at the anal fin origin. The standard length is three to three and a half times the depth of the body. The dorsal profile of the head is convex and the preopercle has a rounded lobe at its angle which is has enlarged serrations.

The dorsal fin contains 11 spines and 16-18 soft rays while the anal fin contains 3 spines and 10-12 soft rays. The membranes between the dorsal fin spines are notched with the third and fourth spines being the longest. The caudal fin is square. The adult females and the juveniles are normally pale grey to brown-grey marked with darker blotches and wavy lines that give a marbled appearance to the upper flanks and back. The pelvic, anal, and caudal fins have bluish-black margins. When resting they often assume a camouflage pattern with 5 dark brown saddles separated by white bars along the base of the dorsal fin. The large adult males are typically pale to medium grey in color, with an indistinct reticulated pattern underneath the dorsal fin. They are darker grey or black on the breast and belly, with similar color on the margins of the soft rayed part of the dorsal find the caudal fin, as well as the posterior margins of the pectoral and pelvic fins. There is also a color phase called black-back which has the rear end of the body and all of the soft rayed part of the dorsal fin and the anal fin are black.

This species attains a maximum total length of 145 centimeters (57 in) although 50 centimeters (20 in) is a more common length, and the maximum published weight attained is 36.5 kilograms (80 lb).

Distribution
Mycteroperca microlepis is found in the western Atlantic Ocean where it has a disjunct distribution. The northern population is found around Bermuda and along the eastern coast of the United States from North Carolina south to the Yucatan Peninsula of Mexico but it is largely absent from Cuba, apart from one record of a vagrant. The southern population is found in southern Brazil from Rio de Janeiro State to Santa Catarina State. Juveniles have been recorded in as far north as Massachusetts.