This is an advance summary of a forthcoming article in the Oxford Research Encyclopedia of Neuroscience. Please check back later for the full article.
The predatory stomatopod crustaceans, or mantis shrimp, are some of the most attractive and dynamic invertebrates living in the sea. Among their special attributes are their powerful raptorial appendages, used to stun or disable predators, prey, or competitors, and their highly competent compound eyes. Mantis shrimp vision is unlike that of any other animals yet described and includes numerous unique features. Their eyes are optically triple, with each compound eye having three separate regions that produce overlapping visual fields viewing particular regions of space. They have the most diverse set of spectral classes of receptors ever described in animals, with 16 or more types in a single compound eye. These receptors are based on an extremely well-duplicated set of opsin molecules, more than known for any other species, and on a set of strongly absorbing photo-stable filters present in some photoreceptor types. The receptor set includes six ultraviolet types, all spectrally distinct, many of which also are tuned by photo-stable filters. It also includes eight types of polarization receptors of up to three spectral types (including an ultraviolet class); in some species, two sets of these receptors are devoted to analyzing circularly polarized light, another unique feature. Movements of stomatopod eyes are independent, and they inspect objects using a special set of movements that lead to image foveation and scanning of image features. Stomatopods are known to recognize colors and polarization features and evidently use these in predation and in intraspecific communication. Altogether, these animals have perhaps the most unusual visual capabilities of any creatures in existence.