Pinecone Fish - the weird fish under the blue ocean.

The Pinecone Fish also called the Pineapple Fish and Knight-fish is a small and unusual beryciform marine fish member of the family Monocentridae, of the Order Beryciformes, Class Actinopterygii. It is an unusual armored fish of the Indo-Pacific whose body has a vaguely pinecone pattern made by the joining of hard scutes, which provide protection to the fish from her enemies. There are four species of pinecone fish which are Monocentris japonica, Monocentris meozelanicus, Monocentris reedi, and Cleidopus gloriamaris.

A beautiful sea fish Pinecone Fish

It is 8-15 cm long (3-6 in), and is covered with spines, and has a brilliant yellow body somewhere it can be yellow to orange in color. It has what appears to be a glowing smile due to the bioluminescent bacteria which inhabit the light organs found on the sides of the mouth. All pinecone fish have phosphorescent organs at either side of the lower jaw that can turn off and on by movement of the jaw. It has a large, blunt head, and interestingly, its dorsal fin is not situated on the center of its back like that of most fish, but is off-center and the second dorsal and anal fins are at the rear of the animal, pointing backward.

This fish generally seeks shelter by day in caves, crevices and under overhangs. It lives in tropical and sub-tropical waters. The pinecone fish is popular in tropical aquariums due to its unusual appearance, but it is considered a difficult fish to keep.

Origin from Australia, Coral Sea but their distribution is limited to tropical and subtropical waters of the Indo-Pacific.