Ostracod

Gigantocypris is a deep-sea ostracod, living at around 1000m depth as plankton. Most ostracods are pretty small around half to 2 mm - barely visible to pepper corn sized. Gigantocypris, true to their name are ostracod giants, up to 3 cm in width - ping pong ball-sized. They are caught from big research ships in plankton nets... In life, where people live at least, they are orange-red in color. But in their native deep sea habitat, long wavelength light does not penetrate the ocean very far, so their orange pigment would not reflect any light...

Perhaps the most amazing feature of Gigantocypris is their eyes. In most animals' eyes, light is bent and focused with lenses. But a select few bend light with mirrors. Gigantocypris is one of the few, bearing a huge pair of parabolic reflectors behind light sensitive patches... 

Image reportedly from Ciencia Polar, via Evolutionary Novelties, Let's do Some Zoology, and Mad as a Marine Biologist.