Within the toxic dinoflagellate genus Prorocentrum only a few species are known to produce okadaic acid and its derivatives and dinophysistoxins, which are responsible for Diarrhetic Shellfish Poisoning (DSP), as well as pectenotoxins and yessotoxins, which are not associated with DSP. The high biomass of Prorocentrum cordatum can also severely reduce the amount of oxygen available to living resources resulting in local fish kills. High density blooms of Prorocentrum can cause water to become discolored reddish-brown. P. texanum has two morphotypes so this information will inform on the differences. P. cordatum (PcorA) is a new isolate from the Gulf of Mexico