The variations in both free-living and symbiotic Symbiodiniaceae communities were studied in Sanya coral reefs of Hainan. These Symbiodiniaceae ITS sequencing were from a total of 69 healthy coral fragments and coral surrounding surface seawater sampled in March and July 2017. Coral species were Acropora digitifera, Acropora hyacinthus, Favites flexuosa, Galaxea fascicularis, Montipora truncata, Porites lutea,
Pocillopora damicornis. The ribosomal internal transcribed spacer 2 (ITS2) of Symbiodiniaceae nuclear ribosomal DNA (rDNA) region was amplified through polymerase chain reaction (PCR) with the ITS2-forward (5'-GTGAATTGCAGAACTCCGTG-3') and ITS2-reverse (5'-CCTCCGCTTACTTATATGCTT-3') primers. Less...