Symbiodinium spp. diversity in a single host species, Galaxea fascicularis, Vietnam : Impact of environmental factors, host traits, and diversity hot spots

• We determined the distribution of zooxanthellate ITS2 types within one broadcast spawning coral species,Galaxea fascicularis with horizontal symbiont uptake, in both inshore and offshore reef habitats over a 3200 km range along the coast of Vietnam, covering 11 degrees of latitude. Host traits (mtDNA genotype) and environmental factors (visibility, sea surface temperatures and Chlorophyll a derived from satellite data, regional measures of coral species diversity and distance from land (inshore/offshore)) were measured to test whether symbiont type distribution was determined by host characteristics or by environmental factors. The G. fascicularis and their associated symbionts were not genetically coupled to each other but to environmental factors The host displayed an inshore-offshore zonation, with higher diversity offshore. The D1a symbiont exhibited an inshore- offshore zonation. In contrast; the 5 different C symbiont types showed a latitudinal distribution gradient, which shifted in dominance north to south. We found regional differences in symbiont type; these were related to environmental differences and not to genetic characteristics in the coral G. fascicularis.

Keyword

Marine Ecotoxicology

marin ekotoxikologi

Publication and Content Type

vet (subject category)

ovr (subject category)