Giant Damselfish, Microspathodon dorsalis: The Giant Damselfish is characterized by its size and by its trailing, filamentous dorsal and anal fins.
The edges of its major fins may also be white-rimmed. Juvenile Giant Damselfish have less developed fins and can vary in color from blue (with color generated by small bright blot spots on each scale) to yellow, and various mixtures.
This fish species is similar in appearance to the Acapulco Major, Stegastes acapulcoensis, the Bumphead Damselfish, Microspathodon bairdii, the Cortez Damselfish, Stegastes rectifraenum, and the Oval Damselfish, Chromis alta, but all of the above lack the trailing ventrical fins.
These fish are normally found around large boulders just beyond the surge zone within the first 75 feet of the water column. The Giant Damselfish is very aggressive when feeding habits and defending its territory. It reaches a length of approximately 12 inches and about 1 pound in size.
The Giant Damselfish is a member of the Pomacentridae or Damselfish Family of small, very colorful reef fishes.