Ceratium

Ceratium is a genus of dinoflagellate protists of the class Dinophyceae, order Gonyaulacales, family Ceratiaceae, with two heterocontous flagella on the sulcus and cingulum. The teak plates have long extensions. Its cells are asymmetric, dorsiventrally compressed; thick, conspicuous plates, often reticulate, with processes or horns, one anterior and 2-3 posterior; in the middle ventral part there is a thick and developed plate, discoid and numerous chromatophores. The species of this genus, along with Peridinium, are the most common on the Peruvian coast; few are freshwater.