At least two chemicals are needed to create luminescence. the light creating chemical is lucirefin. it is in an idle state and must me mixed to become luminescent. when mixed with oxygen and an ion such as calcium, the molecule can become luminescent.
There six species of flashlightfish in the world. They live in deep, coral reef drop offs during the day and ascend to shallow waters at night to feed on prey. their prey is attracted to the bioluminescent organ right under the fishes eye.
The light organ of the flashlightfish is attached by cartilage and has a lid that can be shut to block out the light to make the fish seem like it is blinking. The bright light is produced by luminescent bacteria. The light produced can be seen from over 100 feet and is the brightest light produced by any living creature. when trying to run from a predator, the flashlightfish will swim away, changing direction while blinking the light off and on to confuse its predator.
Most comb jelly fish can create light. here are some examples of bioluminescent jellyfish.
