Anomalopidae


Anomalopidae are a family of beryciform fish distinguished by bioluminescent organs located underneath their eyes, for which they are named. These light organs contain luminous bacteria and can be "shut off" by the fish using either a dark lid or by being drawn into a pouch. They are used to communicate, attract prey, and evade predators.
Flashlight fish are found in tropical ocean waters across the world. They are typically about in size, although some species can reach twice this length. They are nocturnal, feeding at night on small crustaceans. Some species move to shallow waters near coral reefs at night, but otherwise, they are exclusively deep water fish. This tends to make their collection difficult, and as such they are a poorly understood group.