ABSTRACT
Cubozoan medusae are noted for behavior more complex than other cnidarian classes and for possessing rhopalial sense organs that include multiple complex eyes with spherical lenses. Tripedalia cystophora, a small cubozoan medusa, was the subject of field observations in southwestern Puerto Rico concerning the role of its complex eyes. A behavioral repertoire was established with in situ observations among mangrove prop roots. Medusae show an attraction to light shafts that penetrate the mangrove canopy and in which their copepod prey are commonly found. Non-breeding medusae feed actively on copepods in or near light shafts; breeding males and gravid females do not feed, yet breeding males exhibit the highest level of activity in an apparent search for mates. Because mating in T. cystophora can be described as a form of copulation, an image-forming role for the complex eyes in mating behavior is a logical assumption, but neither observational evidence in this study nor optical theory supports such a role.
