Ostorhinchus fleurieu

Lore & Background

The species was described with the specific name honoring the French explorer and hydrographer Charles Pierre Claret, comte de Fleurieu (1738-1810), a colleague and friend of Lacepède's. It is a coppery-coloured fish reaching up to 12.5 cm in length, with a broad blackish bar at the base of the tail. In juveniles, the base of the tail has a spot rather than a bar. The upper jaw has a narrow blue streak, and a broad, blackish stripe extends from the front of the snout to the eye. It is easily confused with Ostorhinchus aureus, where the black tail bar is narrower in the centre than at the ends.

Reader's Guide

Ostorhinchus fleurieu holds significance as the type species of the genus Ostorhinchus, anchoring the taxonomic identity of a large group of cardinalfishes. Its wide distribution across the Red Sea, Persian Gulf, Gulf of Oman, East Africa, Seychelles, India, Sri Lanka, the Indo-Malayan region, Hong Kong, and south to the Ashmore Reef, Western Australia, makes it a broadly encountered species in tropical Indo-Pacific coral reef habitats. Adults occur in small schools made up of pairs of fish from seven metres to at least seventy-three metres in depth, associated with coral reefs, normally in shallow areas with moderate currents. It is found with small to large schools which shelter in crevices. The species is easily confused with Ostorhinchus aureus, distinguished by the shape of the black tail bar. Its multiple common names—flower cardinalfish, gold cardinalfish, bullseye cardinalfish, ring-tail cardinalfish, and ringtailed cardinalfish—reflect its varied appearance and recognition among observers.

Did You Know?

• Ostorhinchus fleurieu is the type species of the genus Ostorhinchus.
• Juveniles have a spot at the base of the tail, while adults have a broad blackish bar.
• It is easily confused with Ostorhinchus aureus, which has a tail bar narrower in the centre than at the ends.