Aequorea macrodactyla is a species of hydrozoan in the family Aequoreidae.

[2] Bioluminescence is a common feature among marine organisms.

The luminescent system of A. macrodactyla is similar to a related species, A. victoria, and consists of a 27-kDa green fluorescent protein and the aequorin complex which consists of a 22-kDa apoaequorin, the luminophore coelenterazine, and molecular oxygen.

As calcium binds to coelenterazine, (a bioluminescent molecule in sea life), the molecule oxidizes which results in the release of carbon dioxide and blue light.

This is due to a difference in intron length in GFP.