Description:
The sergeant major is a compressed and deep bodied fish that grows to a length of approximately 7 inches.  Body color is blue-green to grey-blue dorsally, often with a saddle of yellow or greenish-yellow along the back under the dorsal fin.  Spines and soft rays of the dorsal fin are not separated.  There are 5 black bars that run vertically beginning at the gill plate and extending to the caudal peduncle.  A dark spots marks the base of the pectoral fin.  The caudal fin is forked.

Habitat:
The sergeant major is a common inhabitant of coral reefs, jetties, docks and pilings, and rocks.  They also utilize seagrass beds and mangrove areas.  Juveniles are known to associate with the floating algae Sargassum. 

Similar Species:
The yellow area under the dorsal fin separates the sergeant major from other local damselfishes.

Range:
Sergeant majors range from Rhode Island south along the U.S. coast to Brazil and Uruguay, including Bermuda, the Gulf of Mexico, and the Caribbean.