photophore

A photophore is a light-emitting organ which appears as luminous spots on various marine animals, including fish and cephalopods. The organ can be simple, or as complex as the human eye; equipped with lenses, shutters, color filters and reflectors [1]. The light can be produced from compounds during the digestion of prey, from specialized mitochondrial cells in the organism, called photocytes ("light producing" cells) , or, similarly, associated with symbiotic bacteria in the organism that is cultured.

The character of photophores is important in the identification of benthic fishes.

Photophores on fish are mainly used for attracting food or confusing predators.

Photophores are also on some Cephalopods, most notably the Firefly Squid (also known as the Sparkling Enope Squid) which can create large light displays.

In medicine, the photophore is an instrument (a type of endoscope) used to observe internal organs and tissues.

Compare: chemoluminescence, bioluminescence, biophoton

See also

• Chromophore

References

1. Photo, diagram and description of a cephalopod photophore