Reproductive behavior, larval development and rearing of captive cardinalfish, Ostorhinchus ishigakiensis (Ida and Moyer) in the tank

Reproductive behavior and morphological changes in aquarium-held juvenile cardinalfish, (Ostorhinchus ishigakiensis) are reported. Before spawning of the parental pair, the male actively moved toward the female whilst exhibiting courtship behavior (mouth opening and lower jaw isthmus inflated). Just before spawning, the female acted aggressively toward the male, pulling and chewing on its abdomen, before both fish repeatedly positioned their abdomens together, each shaking its tail violently. Post spawning, the male held the egg mass in its mouth until hatching, 12 or 13 days later. Newly-hatched larvae were 3.82-4.09 mm in total length, with a small yolk. They reached 6.20-11.40 mm in total length 20 days after hatching, at which time the number of fin spines and rays reached the final complement for the species. Thirty days after hatching, juveniles were 8.27-16.95 mm in total length and had similar first dorsal fin spotting as the parents. Eggs were noted in the abdomen of individuals which died 260-400 days after hatching.