Note
We have discovered that blue-green light is emitted from the suckers of a deep-sea finned octopod, Stauroteuthis syrtensis. The light organs have characteristics of both simple photophores and suckers, suggesting that they could have evolved from suckers. The function of the light is unknown, but it may be related to the non-bioluminescent sucker signalling used by shallow-water octopods, or act as a lure for prey.