Ontogeny of the mandarinfish Siniperca chuatsi (Perciformes: Sinipercidae) reared in aquarium

Abstract

Early-stage morphologies of the mandarinfish Siniperca chuatsi are described on the basis of an ontogenetic series of reared specimens in an aquarium. Spherical eggs (diameter 1.70–1.82 mm) with a single oil globule (0.40–0.48 mm) were free-demersal and easily floated when agitated. Hatching occurred about 3 days after spawning at about 24°C. Newly hatched larvae (3.8–4.2 mm in notochord length: NL) had many melanophores on the yolk sac. After reaching ca. 5.5 mm NL (8–9 + 19–20 = 27–28 myomeres), larvae had almost completely absorbed the yolk, possessed a large mouth and sharp teeth, and were starting to prey on other fish larvae. Three large preopercle spines appeared at ca. 5.5 mm NL, five spines by ca. 8.5 mm NL, and eight by ca. 21 mm in standard length (SL). The interopercle bore a single spine at ca. 8.5 mm NL and two spines at ca. 13.5 mm SL. A single spine appeared at the supracleithrum and another at the opercle at ca. 10 mm SL. Dorsal fin spines and pelvic, anal, and caudal fins were completed at ca. 10 mm SL. Dorsal fin rays and pectoral fins were completed at ca. 13.5 mm SL. Four ontogenetic characters (free-demersal eggs, large jaws with large teeth, conspicuous head spination, and precocious completion of dorsal fin spines) are rare among freshwater percoids.