Larva of <i>Platynereis</i> (IMAGE) National Institutes of Natural Sciences Caption Larva of Platynereis possesses photoreceptor cells in the brain. In the cells, a UV-sensitive opsin receives and transmits ambient UV signals, probably resulting in regulation of circadian behaviors such as diel vertical migration. Credit INSTITUTE FOR MOLECULAR SCIENCE Usage Restrictions None License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.