Pinecone Fish

Monocentris japonica

Although this species is officially known as the pinecone fish, it is more commonly referred to in South Africa as the pineapple fish. This is because it closely resembles the fruit, thanks to its round shape and overlapping black-edged yellow scales. It is found throughout the Indo-West Pacific, usually at depths of between 20 and 200 metres. The pinecone fish is nocturnal, and spends the daylight hours sheltering beneath ledges or in caves. It grows up to 17 centimetres in length, and has a small organ on either side of its chin that uses luminescent bacteria to emit light. Although it isn’t certain what these organs are for, it is likely that the fish uses them to warn off predators, attract prey or communicate with other pinecone fish in the dark.