Australian bass have a moderately deep, elongated body that is laterally compressed. They have a forked caudal ("tail") fin and angular anal and soft dorsal fins. Their spiny dorsal fin is of medium height, strong and sharp. They have a medium sized mouth and relatively large eyes than can appear dark in low light or red in bright light. The opercula or gill covers on Australian bass carry extremely sharp flat spines that can cut fishermens' fingers deeply.
Australian bass vary in colour from gold in clear sandy streams to the more usual bronze or bronze-green colouration in streams with darker substrates and/or some tannin staining to the water.