Splendid Lantern Shark

Skin photophores surrounding the defensive dorsal spines present on E. splendidus show a pattern supporting an aposematic function for the bioluminescence of this species. Aposematism is the use of warning coloration to inform potential predators that an animal is poisonous or venomous. Despite the absence of poison or venom in E. splendidus, aposematic mimicry is believed to be used in its bioluminescence surrounding these defensive dorsal spines. This mechanism was documented for the first time in situ by video recordings in 2016. E. splendidus has a translucent area present in its upper eye orbit which plays a part in a reference system for counterillumination adjustments. This unique feature also acts as a spectral filter for camouflage breaking. Rental specializations amongst these sharks aid in prey detection and help reflect lifestyle differences between very similar species of deep sea sharks such as Etmopterus spinax and Etmopterus molleri. These bioluminescent sharks possess higher rod densities, which might provide them with improved temporal resolution - particularly useful for bioluminescent communication during social interactions. Luminous Etmopterus sharks swim faster than other deep sea species. …