Synonym :
Peridinium furca Ehrenberg 1836

Morphological Characteristics :
The organism has a wide girdle and rather straight anterior horn. Hypotheca in triangular shape and slightly tapering, extended into long left and short right antapical horns. Thecal plates are moderately thick, ornamental with a regular reticulum of ridges with pores in the depressions.

Size of Specimen :
100-200 mm (L), 30-50 mm (W)

Distribution :
Cosmopolitan; normally appeared at the surface waters of tropical and subtropical regions. Widely distributed in the northern part of the South China Sea. Frequently associated with red tides in the eastern waters of Hong Kong and in Dapeng Bay.

Major Limiting Factors :
Dissolved inorganic phosphates (DIP) and dissolved inorganic nitrogen, with optimal growth at N:P atomic ratios of 12-22.

Toxicity :
Non-toxic; harmful to marine organisms due to oxygen depletion at high cell concentration.