Sound production by Simochromis diagramma (Günther) (Pisces, Cichlidae)

Two types of sounds produced by the cichlid fish Simochromis diagramma, are recorded and analysed. A br-r-r sound, with a main frequency of 200 Hz and a chewing sound with a main frequency of 6,000-10,000 Hz are produced during threatening; the former sound can also be heard during quivering. No sound was recorded with fighting or anxious fishes.