Gonyaulax schuetti Lemmerrann 1899
Protoceridinium pgrophynum Pouchet 1883
Morphological Characteristics :
Epitheca is almost as long as hypotheca. Flattened apical spine. Wide and deep sulus, slightly surrounded by plates. Many protruding spines at the surface of plates. Nucleus lies in the posterior end, big and ovum.
Size of Specimen :
48 mm (L), 33 mm (W)
Distribution :
Commonly seen at temperate, subtropical and tropical waters. Caused numerous red tide in Hong Kong and Dapeng Bay at the late eighties to early nineties. Also frequently reported as red tide causative organism in Japan.
Major Limiting Factors :
Closely related with supplies of inorganic nitrogen and soluble phosphates. Also positively correlated with COD in seawater. Favoured by low salinity and low manganese (Mn) ions. Optimally grown at 17 to 22°C.
Toxicity:
Non-toxic; may cause massive fishkill because of oxygen depletion.
