Alexandrium tamarense

Alexandrium tamarense is a species of dinoflagellates known to produce saxitoxin, a neurotoxin which causes the human illness clinically known as paralytic shellfish poisoning (PSP). Multiple species of phytoplankton are known to produce saxitoxin, including at least 10 other species from the genus Alexandrium.

Alexandrium tamarense
Scientific classification
Domain:	Eukaryota
Clade:	Sar
Clade:	Alveolata
Phylum:	Dinoflagellata
Class:	Dinophyceae
Order:	Gonyaulacales
Family:	Ostreopsidaceae
Genus:	Alexandrium
Species:	A. tamarense
Binomial name
Alexandrium tamarense (Lebour) Balech

Recent molecular work shows that this species belongs to the Alexandrium tamarense complex (Atama complex, including A. tamarense, Alexandrium fundyense, Alexandrium catenella) and that none of the three original morphospecies designations forms monophyletic groups in the present small ribosomal subunit (SSU)–based and previous large ribsosomal subunit (LSU)–based^[1] ribosomal RNA phylogenetic trees, i.e. these species designations are invalid.^[2] A. tamarense contains polyunsaturated fatty acids, including docosahexaenoic acid.^[3]