The pineapplefish, or knightfish, keeps to dark caves all day, coming out at night to hunt small shrimp.
When spawning, the female deposits thousands of eggs close to the ocean floor, which the male immediately fertilizes.
This fish possess light organs on either side of its mouth. Those photophores contain luminescent bacteria. They are green in young specimens, changing to red with age. The animal can control the light it gives off by completely obscuring its photophores. This can be used as a sign of recognition between animals of the same species and can also serve to attract its prey at night.