Damselfishes

Scientific name : Pomacentridae

The Pomacentridae rank amongst the more diverse fish families, with over 300 known species living in tropical and temperate seas. Besides this, they are probably the commonest fishes on a reef environment, because many species are very abundant and live in large shoals. Damsel fishes are small size fishes, with relatively deep, compressed body, terminal small mouth. One single, continuous, dorsal fin. Many species have bright colours, in some cases the juvenile has a different colour from the adult. Scales are relatively large. Tail is V shaped, but round in anemone fishes. The meaning of the scientific name Pomacentridae is "spiny operculum", and it refers to small spikes along the gill operculum. The Plankton feeders often have mouth opening in a tube shape. Damselfishes can be divided into 4 ecological groups: 1- The plankton feeders, living in shoals. Normally they hover close to the coral reef, ready to dive amongst the corals to avoid predation. They live in many environments, but they are abundant on reef front and external reef, some species in lagoon. The genera Chromis, Dascyllus, Acanthochromis, Neopomacentrus, Amblyglyphidodon, Abudefduf are included in this category. 2- The symbiotic plankton feeders, living in symbiosis with a sea anemone, strongly territorial, that is the anemone fishes. they live along the reef front, and they include the genera Amphiprion and Premnas. 3- The territorial herbivorous, grazing on seaweeds in small territories, that they defend mainly against other herbivorous invaders. They live mainly in lagoon and back reef. Included here are the genera Plectroglyphydodon, Stegastes, Dischistodus. 4- Omnivorous species, living, solitary or in small shoals close to their shelters, in lagoon and back reef. They include the genera Pomacentrus, Chrysiptera, Neoglyphidodon. The benthic eggs are laid in nests guarded by the male. They give birth to planktonic larvae, dispersed by the currents. Only one species, Acanthochromis polyacanthus, has no larval stage and the juveniles are guarded by both parents. Normally they are quite easy to identify as a group. The shoals of plankton feeding damsel fish can be confused with shoals of Anthiases (fam. Serranidae), living in the same environment and showing a similar behaviour. Normally anthiases are more elongate, have larger mouth and longer fins, especially the tail, and often are orange-red or purple in colour. Damsels are normally black, yellow, blue, green or brown. The snout profile, convex, and the less compressed shape, distinguish them from butterfly fishes. Sometimes can be easy to confound damsel fishes with some small size angel fishes, but the latter have always a backward spine on the gill operculum.