Gambierdiscus pacificus is a species of toxic (ciguatoxin- and maitotoxin-like toxicity) dinoflagellate. It is 67âÂÂ77 üm long and 60âÂÂ76 üm wide dorsoventrally and its surface is smooth. It is identified by a four-sided apical pore plate surrounded by 30 round pores. Its first plate occupies 20% of the width of the hypotheca.