It is a unicellular marine alga belonging to the dinoflagellate phylum. These protist species are known for their two flagella, used for aquatic movement, and they exhibit bioluminescence triggered by water motion, often seen near ships, waves, or in response to predators.The cells are elongated and taper at the ends, with an average size of 970 x 163 µm and a spherical diameter of about 374 µm3. While they have cell walls, they lack an additional rigid polysaccharide sheathing called thecae that forms the cytoskeleton.