Longfin Damselfish

Stegastes diencaeus

There are three, dark colored damselfishes when adults. The three species are much easier to identify when juveniles. The Longfin adult damselfish gets it's name because it's dorsal and anal fins exrtend beyond the base of the tail. The other two dark colored damselfishes do not. ( Cocoa and Dusky) The Longfin Damselfish can also be identified by a bright almost neon blue edge on the anal fin. The Dusky Damselfish has a dark edge on the dorsal and anal fin, but no blue.