Meeting Abstract
Sacoglossan sea slugs feed suctorially on coenocytic, green macroalgae and several species store algal chloroplasts for photosynthesis within specialized cells in the digestive tubules. The diets of most sacoglossan species are reported to be highly specialized, with many only feeding on only species of algae. However, several recent studies identifying algal donors using chloroplast genes have found that some slug species use a much wider range of food sources. Furthermore, these molecular based studies found that much of the earlier literature on sacoglossan food sources, which relied on field surveys and slug proximity to algae to determine diet, was incorrect. In this study, we used the PCR determined sequence of the chloroplast gene ribulose bisphosphate carboxylase/oxygenase (rbcL) to identify the algae consumed by Elysia crispata from five (Curacao, Barbados, Virgin Islands, Panama and Dry Tortugas) locations throughout its range within the Caribbean. Results indicate that E. crispata has a wider diet than previously realized and several new species of algal food were identified for the slug. Diet also was unique among locations. Although E. crispata is widespread throughout the Caribbean, it does not show a consistent dietary pattern across its range. This could be due to either local adaptation or an opportunist feeding strategy by the slug.
