Ostorhinchus fleurieu (flower cardinalfish, gold cardinalfish, bullseye cardinalfish, cardinalfish, ring-tail cardinalfish or ringtailed cardinalfish) is a species of cardinalfish native to the Red Sea and Persian Gulf, the Gulf of Oman, and the waters around East Africa, Seychelles, India, Sri Lanka, the Indo-Malayan region, and Hong Kong., south to the Ashmore Reef, Western Australia. It is the type species of the genus Ostorhinchus. The specific name honours the French explorer and hydrographer Charles Pierre Claret, comte de Fleurieu (1738-1810) who was a colleague and friend of Lacepède's.