Biodiversity and conservation of “solar-powered” sea slugs from the Western Atlantic under climate change scenarios

Elysiais a genus of sea slugs in which some species can “steal” chloroplasts (kleptoplasty) from algae and keep them photosynthetically active inside their cells. Solar-powered animals are more susceptible to climate change as photosynthesis can increase the stress for these animals in extreme environmental conditions. Here, we used the Maxent algorithm and environmental envelopes (i.e. the multi-dimensional environmental space in which a species can occur) to model the ecological niche of 21 Elysia species in the Caribbean to estimate their current and future potential distribution. We then used predicted distributions to map potential taxonomical richness and to describe the representation of the genus inside the marine protected areas (MPAs). For most species, we show an expansion of the northern and southern range of distribution, but a reduction in the central part. Although changes in richness appeared in different areas, predictions emphasize four large extensions that have a potential current richness of 13 and will have no species in the future: Pamlico Sound, North Carolina; the southwest of the Gulf of Mexico; the Great Bahama Bank; and the southwest of Brazil. Out of the total area with environmental conditions adequate for at least one of the species in the genus, 24.7% is located within MPAs.