Harmful Dinophysis species: A review

Several dinoflagellate species of the cosmopolitan genus Dinophysis produce potent lipophilic shellfish toxins (okadaic acid, its derivatives and the pectenotoxins) and pose a major threat to shellfish aquaculture in Europe, Chile, Japan, and New Zealand. They usually constitute a small percentage of the microplankton community and their observation has required the use of species-specific sampling strategies. For years the genus has challenged microalgal physiologists as difficulties in maintaining species in culture has hampered developments in understanding, for example, their distinct cryptophyte-like pigments. This document reviews recent advances in our study of harmful Dinophysis species: insights into the nutrition of the organisms; the ability to culture certain species fed on the phototrophic ciliate Mesodinium rubrum; knowledge on their population dynamics gained through subtle field applications of techniques of measuring growth rate; and the in situ use of field instruments which have a capacity to sample biological material with a high spatial-temporal resolution. These methods have all contributed to improvements in our knowledge of the genus summarised below with respect to their physiology, ecology, modelling and monitoring. This review also identifies the main gaps required to progress on improved predictions of the initiation and decay of Dinophysis blooms, and to solve the intricacies concerning their nutritional sources and the origin of their plastids.