Meeting Abstract
Stomatopod crustaceans possess extraordinary visual systems and other unique adaptations. Stomatopod eyes contain dozens of opsins, the protein portion of a visual pigment. Until now, no studies have identified extraocular light detectors or explored opsin diversity in non-ocular stomatopod tissues. Extraocular light detectors are prevalent across animal phyla and are important for many functions, including circadian function, photolocomotory responses, and reproduction. Here, we provide behavioral and molecular evidence for extraocular photoreception in stomatopods. Sighted and blinded stomatopods flip, walk, and/or swim when illuminated more frequently than in the dark. Blinded animals responded more slowly to a light stimulus, indicating the extraocular light detectors control processes that occur on a different timescale than ocular light detectors. In a search for photopigments that could be responsible for light detection outside the eyes, we obtained transcriptomes from three separate regions of the central nervous system (CNS) of the stomatopod, Neogonodactylus oerstedii. Our transcriptome analyses and RT-PCR suggest that at least four opsins are expressed in the CNS. These data indicate that stomatopods probably possess opsin-based extraocular photoreceptors. Future work will explore the location and possible electrophysiological photoresponses of these putative photoreceptors.
