are a medium-sized freshwater fish endemic to the Murray-Darling river system in south-eastern Australia. Their scientific name comes from an aboriginal name for the species — Bidyan — recorded by Major Mitchell on the Barwon River on his 1832 expedition. (Mitchell's original scientific name for the species was Cernua Bidyana.) Silver perch are not a "true" perch of the Perca genus, but are instead a member of Terapontidae or 'grunter' family. They are the largest member of the Terapontidae family, capable of growing in excess of 60 cm and close to 8 kg, but today wild river specimens are typically 30–40 cm and 1.0–1.5 kg.