Erratum to: Coral Reefs DOI 10.1007/s00338-015-1264-4

Throughout the manuscript ‘Widespread prevalence of Symbiodinium D in the key Caribbean reef builder Orbicella annularis,’ we used the term ‘Symbiodinium D1’ to describe the symbiont/s targeted by our screening technique. Since our RT-PCR primers lacked the specificity to distinguish among members of Clade D, we were not able to unambiguously confirm that the symbiont we were detecting at low abundance background concentrations was type D1a, otherwise known as D1-4 (despite this being the only type we identified using DNA fingerprinting). We adopted ‘Symbiodinium D1’ as a generic term for both D1 and D1a throughout the manuscript. It has become apparent that our use of the term ‘D1’ to mean either type D1a or D1 may be confusing to readers. Type D1 corresponds to Symbiodinium associated with Acropora and Pocillopora from the Indo-Pacific (LaJeunesse et al. 2010). Type D1a is thought to be the only representative of Clade D found in the Caribbean (Finney et al. 2010), and LaJeunesse et al. (2014) have described D1a as a distinct species, Symbiodinium trenchii. Given our data and the biogeographic evidence, the most parsimonious interpretation of our results is that symbiont detected (by both techniques) in our study was Symbiodinium trenchii. Therefore, to clarify, any reference to ‘Symbiodinium D1’ in this paper might reasonably be assumed to be Symbiodinium trenchii, also known as D1a or D1-4.

We thank Prof. T. LaJeunesse (Penn State University, USA) for access to unpublished findings relating to the systematics and distribution of Symbiodinium clade D variants.