Very common on shallow rocky areas among seaweed.  Color and pattern can be altered at will but the alternating bars and oval spots are distinctive, nuptial males may be dark with red fins.  Attains 5.5 inches.  Red Sea to Japan, east to Micronesia and Samoa.  Several fish were seen in October 2022 at Sand Island, Oahu, Hawaii, which may be aquarium releases or recent settlers from the Equatorial Pacific.