Visual predation by a marine cyclopoid copepod, Corycaeus anglicus

In an experimental study the cyclopoid copepod Corycaeus anglicus Lubbock was found to ingest Artemia nauplii at much higher rates (up to 15 times) in the light than in the dark. Maximal ingestion rates observed in the light represent daily rations of 70% and 66% of the body carbon for males and females respectively. From experimental observations together with studies of the ultrastructure of the photoreceptors it is suggested that Corycaeus can locate prey visually. This is in contrast to the majority of other copepods which use chemoreceptors and mechanoreceptors.