News / Species Spotlight / Species Spotlight - Blue Star Damselfish (Pomacentrus alleni) (11/22/17)

Species Spotlight - Blue Star Damselfish (Pomacentrus alleni)

Species Spotlight- Blue Star Damselfish (Pomacentrus alleni)
Damselfishes get a bad rap among aquarists, but there are many stellar choices in this family that are actually quite harmless and can provide an impressive splash of color and motion. A perfect example of this is the vibrant Pomacentrus alleni.

This species occurs only in the Eastern Pacific Ocean, with reports from throughout the Andaman Sea and south along Sumatra, Java and rarely as far as Bali. Further east from here, it seems to get replaced by the Blue & Gold Damselfish (P. auriventris). The scientific name honors legendary ichthyologist and damselfish authority Dr. Gerry Allen, and, interestingly, it was first described by William Burgess in an issue of Tropical Fish Hobbyist. Additional common names for it include the Andaman Damselfish and, appropriately enough, Allens Damselfish.

P. alleni belongs to a group of highly similar species which share a common motif of a shiny blue body and yellow fins, but among these it is easily recognized for the black marking present on the caudal fin, as well as the rather dark dorsal fin.

All of these related species (P. coelestis, P. similis, P. caeruleus, P. micronesicus, P. auriventris) form large shoals that hover high above the substrate to feed on zooplankton. For this reason, these are generally less aggressive than what we see in the more strictly benthic species that browse upon algae. In an aquarium, a small to large group is strongly recommended, though single specimens will generally fare fine in smaller tanks with docile tankmates. Most any food will be accepted, but frozen crustaceans will most closely replicate the natural diet. And, of course, these are perfectly reef safe!