Records of toxic benthic dinoflagellates have dramatically increased along the Mediterranean coasts over the last decade. On the western coasts, toxic Ostreopsis ovata strains have been associated with human health problems due to production of palytoxin-like (p-PLT) toxins, whereas, on eastern Mediterranean (Greek) coasts, the presence of dense Ostreopsis spp. populations has resulted in shellfish contamination by similar p-PLT compounds. Furthermore, available data from 6 years of Greek regulatory monitoring for marine lipophilic biotoxins on shellfish indicate that benthic dinoflagellate toxins are responsible for at least 30% of positive shellfish samples each year. Additionally, the recent detection of dinoflagellates once considered as tropical, such as the ciguatera-causing genus Gambierdiscus, constitutes another impending hazard for both the fisheries industry and consumer health in the Mediterranean Sea. The fact that potentially toxic benthic dinoflagellates are seldom detected in the water column samples obtained as part of regulatory monitoring for potentially toxic phytoplankton (Regulation EC 854/2004) makes the addition of benthic dinoflagellates to the regulatory monitoring for potentially toxic microalgae and the expansion of the regulatory monitoring for marine biotoxins to additional marine edible organisms, such as fish, indispensable.