About Stegastes planifrons (Cuvier, 1830)
Adult threespot damselfish (Stegastes planifrons) are brownish-grey bony fish with a dusky yellow sheen, and a large black spot at the base of their pectoral fins. They reach a maximum length of 13 cm. Their large dorsal fin has 12 spines and 15 to 17 soft rays, while their anal fin has 2 spines and 13 to 14 soft rays. Neither the pectoral fins nor the pelvic fins have spines. Juveniles are a much brighter yellow than adults. They have several tiny blue spots on the head and upper body, including one on the upper iris. Juveniles also have three distinctive black spots: one at the junction between the spiny and soft-rayed sections of the dorsal fin, one on the dorsal side of the caudal peduncle, and a smaller third spot just above the base of the pectoral fins. These black spots typically have a faint blue rim. The pectoral spot is absent in very young juveniles, and grows more prominent as the juvenile ages. This species occurs in the western Atlantic Ocean at depths down to approximately 30 meters (98 feet). Its range extends from Florida, through the Caribbean Sea, to the Bahamas. It is a demersal fish that prefers inshore and offshore coral reef habitats. It is often found among staghorn coral, and may shelter in caves at night.
