Dinophysis

Dinophysis is a genus of approximately 100 dinoflagellates that are common in tropical and temperate waters worldwide. The genus is able to thrive in water temperatures ranging from the Arctic Circle to the tropics and is clearly established in the Atlantic, Pacific, and Indian basins. The name Dinophysis originates from Greek meaning "terrible nature".

Dinophysis cells can be recognized by their reduced epithecal plates and collar like structure. They are relatively oval with dorsal ventral flattening and are between 35-50 µm long. Some thecal characteristics can be used to recognize separate species within this genus although, each species may have a series of shapes due to their polymorphic life cycle and feeding behavior making species specific identification more challenging. These dinoflagellates are known mixotrophs, meaning they do not rely on autotrophy or heterotrophy alone. They obtain resources partly by preying on another predatory plankton species, Mesodinium, but also performing photosynthesis by integrating the chloroplasts of the prey they consume. Mesodinium feeds on a phototrophic group of plankton, the cryptophytes, which places Dinophysis as the top predator of this three-tiered ecosystem in the water column. Dinophysis itself is consumed by filter-feeders, frequently shellfish.

Even though these species have diverse ways of acquiring energy, they are difficult for scientist to maintain in culture due to their heterotrophic ways. Maintaining a culture of Dinophysis requires the creation of this three-tiered food web, rather than simply adding the required nutrients and appropriate light levels as is done for photosynthetic algal cultures. This makes studying on their populations in the lab more challenging.