Prevalent endosymbiont zonation shapes the depth distributions of scleractinian coral species

Abstract

Bathymetric distributions of photosynthetic marine invertebrate species are relatively well studied, however the importance of symbiont zonation (i.e. hosting of distinct algal endosymbiont communities over depth) indetermining these depthdistributions still remains unclear. Here, we assess the prevalence of symbiont zonation in tropical scleractinian corals by genotyping the Symbiodiniumof the 25 most common species over a large depth range (down to 60 m) on a Caribbean reef.