The flathead perch has been an elusive species to find, both for divers on the natural reef and for fish keepers in the saltwater aquarium hobby. The unique and interesting appearance of Rainfordia opercularis, has made it a target of both rare fish collectors and fish breeders, with only the second successful aquaculture of this species being recently announced by Batavia Coast Maritime Institute in Western Australia.
This recent success with such a special fish is only the second time that Rainfordia have been successfully captive bred, the first being by Todd Gardner who has recently turned his attention to Gramma dejongi. Although the flathead perch was recently sighted in Indonesia, Rainfordia are best known from the western regions of Australia so it’s fitting that the commercial effort to produce this species should take place in Western Australia as well.
As the name implies, the flathead perch has a compressed body which is a special adaptation for it to really feel at home between rocks of the reef, living inside the matrix of caves and holes within it. Interestingly, the larvae of Rainfordia opercularis display a highly elongated dorsal filament which is very remarkable, but creates a challenge when trying to culture many specimens in the same aquarium space for growing out.
The rarity of the flathead perch and its unique larval stages presents a very unique aquaculture exercise for budding fish farmers at the Batavia Coast Marine Institute which also has some experience breeding the iconic Royal Gramma, Gramma loreto. It’s very cool to see another breeding program successfully raise a fish which is of very limited, and expensive, availability in the aquarium hobby, especially since this is a fish found in their local waters. Now if we could convince someone at the BCMI to work on the so-rare-it’s-unknown occidental mandarin dragonet, that would be a world’s first!