Habitat: Deep sea; Gulf of Mexico and in the Caribbean Sea
Status: Not Listed
While this deep sea Squat Lobster (Gastroptychus spinifer) may look like its possessed by some otherworldly demon, those bizarre eyes of his actually come in handy in its dark habitat. You wouldn’t normally expect a deep sea crab to have color vision, but in this case it does. 
“A new study published Thursday in the Journal of Experimental Biology finds that some seafloor, or benthic, crabs can see in color. But the crustaceans live in darkness of the deep Caribbean where sunlight does not penetrate, making their sensitivity to blue and ultraviolet light mysterious.

The reason for the color vision, however, may be explained by the concurrent discovery of bioluminescent deep-sea plankton in this environment, which glow blue when they bump against objects along the seafloor. It’s possible that the crabs see this blue glow as a sign of a hearty meal, said study researcher Tamara Frank, a biologist at Nova Southeastern University in Florida.

At the same time, the ability to see blue and UV light would also enable the crabs to tell the difference between bioluminescent blue plankton and the dim greenish glow given off by the anemones where the crabs like to perch.
Anemones would be toxic to crabs, Johnsen realized, while plankton would make a good meal. That’s when he came up with the idea that perhaps the deep-sea crabs have kept their sensitivity to light in order to differentiate between the bioluminescence of the two, essentially color-coding “food” versus “toxin.” (source)
The idea is only a hypothesis at this stage, and thanks to federal funding cuts to deep-sea research, Frank and her colleagues said they may not be able to test it anytime soon, she said. 
I know these eyes aren’t supposed to be scary but…. I mean… I must admit, I’m still a little freaked out over here!