Blowhole Perch

Caesioscorpis theagenes

The Blowhole Perch, also known as the fusilier sweep or southern fusilier, is a slender, schooling fish with a silvery body and a greenish-yellow back. This species is endemic to the southwestern coast of Australia, inhabiting both coral and rock reefs. It is a non-migratory fish that prefers inshore environments. Divers can typically find this fish in temperate waters, as it is associated with reef habitats. The Blowhole Perch is a member of the family Caesioscorpididae, and it is the only species in its genus. Its phylogenetic placement was uncertain for many years, but recent studies have placed it within the order Centrarchiformes. Despite its name, the Blowhole Perch is harmless to humans and is not evaluated by the IUCN or CITES for conservation status. Divers encountering the Blowhole Perch will likely see it in schools, as it is a schooling species. It is most frequently found at depths shallower than 40 meters, making it accessible for most divers.