The retinoids of seven species of mantis shrimp

Eyes of stomatopod crustaceans, or mantis shrimps, contain the greatest diversity of visual pigments yet described in any species, with as many as ten or more spectral classes present in a single retina. In this study, the eyes of seven species of mantis shrimp from three superfamilies of stomatopods were examined for their content of retinoids. Only retinal and retinol were found; neither hydroxyretinoids nor dehydroretinoids were detected. The principal isomers were 11-cis and all-trans. The eyes of most of these species contain stores of 11-cis retinol, principally as retinyl esters, and in amounts in excess of retinal. Squilla empusa is particularly noteworthy, with over 5000 pmoles of retinol per eye.