We wanted to infer the contribution of host vs symbiotic microbiota plasticities on thermal acclimation of the holobiont. We long-term acclimated anymals of the same clonal line to 3 different temperatures (15, 20 and 25°C) and monitored along time the changes in fitness, microbiota composition, and host transcriptome. Overall design: we submitted 15 samples of acclimated female polyps representing 5 replicates from each treatment temperature (15, 20, 25°C).