Molecular identification of Ostreopsis cf. ovata in filter feeders and putative predators

► Identification of harmful species Ostreopsis ovata using qPCR molecular assay. ► Good amplification efficiency and reproducibility of the assay. ► Amplification of DNA quantities equivalent to less than one algal cell. ► Protocol development for the detection of microalgae presence in tissues of predators. ► Correspondence between molecular assay and microscopic observation.