Spiny chromis

Scientific name : Acanthochromis polyacanthus

Medium size chromis, oval, compressed body. The colour is highly variable depending on the geographic location. In our area is uniformly dark brown, almost black, but in neighbouring areas it can be grey, green, with white tail.
Distinguished from the other Pomacentridae for the greater number of spiny rays in the dorsal fin (17 vs. 14 or less). Juveniles are grey with a yellow line. 15 cm. Very common, it lives in large shoals along the reef front, external reef, deep reef. A Plankton feeder. In our area, due to the local colour, confusion is possible with other completely black damsels, as Neoglyphydodon crossi. Compared with this one, A. polyacanthus has deeper body, and the dorsal and anal fins end in a spike (being the posterior part transparent).
The young specimens, when the yellow line fades, are similar to other grey chromis as Chromis ternatensis. Acanthochromis polyacanthus is the only Pomacentridae species to give parental cares to the fry (besides the eggs). There is no larval stage, at the hatching young fish are born, and they never swim far from the parents.