Evidence for coral range expansion accompanied by reduced diversity of Symbiodinium genotypes

• Published in: Coral Reefs
• Main Authors: Grupstra, Carsten G. B., Coma, Rafel, Ribes, Marta, Leydet, Karine Posbic, Parkinson, John Everett, McDonald, Kelly, Catllà, Marc, Voolstra, Christian R., Hellberg, Michael E., Coffroth, Mary Alice
• Other Authors: Biological and Environmental Sciences and Engineering (BESE) Division, Marine Science Program, Red Sea Research Center (RSRC), Institute for Biodiversity and Ecosystem Dynamics, Faculty of ScienceUniversity of Amsterdam, Amsterdam, The Netherlands, Institut de Ciències del Mar, ICM-CSIC, Barcelona, Spain, Centre d’Estudis Avançats de Blanes, CEAB-CSICG, irona, Spain, Department of Biological SciencesLouisiana State University, Baton Rouge, USA, Biology Department, Syracuse University, Syracuse, USA, Department of Biology, Pennsylvania State University, State College, USA, Department of Integrative Biology, Oregon State University, Corvallis, USA, Department of Biological Sciences, University at Buffalo, Buffalo, USA, Graduate Program in Evolution, Ecology and Behavior and Department of Geology, University at Buffalo, Buffalo, USA
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: Springer Nature 2017
• Subjects: Oculina patagonica; Symbiodinium psygmophilum; Zooxanthellae; Microsatellites; Climate change; Symbiosis; North Atlantic
• Online Access: http://hdl.handle.net/10754/623633; https://doi.org/10.1007/s00338-017-1589-2

Zooxanthellate corals are threatened by climate change but may be able to escape increasing temperatures by colonizing higher latitudes. To determine the effect of host range expansion on symbiont genetic diversity, we examined genetic variation among populations of Symbiodinium psygmophilum associated with Oculina patagonica, a range-expanding coral that acquires its symbionts through horizontal transmission. We optimized five microsatellite primer pairs for S. psygmophilum and tested them on Oculina spp. samples from the western North Atlantic and the Mediterranean. We then used them to compare symbiont genotype diversity between an Iberian core and an expansion front population of O. patagonica. Only one multilocus S. psygmophilum genotype was identified at the expansion front, and it was shared with the core population, which harbored seven multilocus genotypes. This pattern suggests that O. patagonica range expansion is accompanied by reduced symbiont genetic diversity, possibly due to limited dispersal of symbionts or local selection. Financial support was provided by the Spanish Government Project CGL2013-43106-R, the Marine Biogeochemistry and Global Change Research Group from “Generalitat de Catalunya” (2014SGR1029) (RC and MR) and NSF-OCE–09-26822 (MAC).