Gonyaulax

Gonyaulax is a genus of dinoflagellates with the type species Gonyaulax spinifera (Claparède et Lachmann) Diesing. Gonyaulax belongs to red dinoflagellates and commonly causes red tides. It can produce yesotoxins: for example, strains of Gonyaulax spinifera from New Zealand are yessotoxin producers.^[4]

Gonyaulax
Scientific classification
Domain:	Eukaryota
Clade:	Sar
Clade:	Alveolata
Phylum:	Dinoflagellata
Class:	Dinophyceae
Order:	Gonyaulacales
Family:	Gonyaulacaceae
Genus:	Gonyaulax Diesing, 1866
Species
Gonyaulax spinifera Gonyaulax apiculata Gonyaulax polygramma Stein 1833[1] Gonyaulax fragilis (Schütt) Kofoid 1911[2] Gonyaulax ellegaardiae Mertens 2015 [3]

Gonyaulax spinifera

Structure

The plate formula in the genus Gonyaulax Diesing was redefined as Po, 3', 2a, 6", 6c, 4-8s, 5'", 1p, 1"".^[5]

Classification

All species are marine, except for one freshwater species, Gonyaulax apiculata.^[5]

It previously included several species, which are now considered to belong to a separate genus, e.g.:^[5]

• Gonyaulax tamarensis (now: Alexandrium tamarense)
• Gonyaulax grindleyi (now: Protoceratium reticulatum)
• Gonyaulax polyedra (now: Lingulodinium polyedra)

Adaptations

Gonyaulax dinoflagellates can produce resting cysts that belong to the cyst-defined genus Spiniferites and other genera ^[6]

Effect on humans

Although some Gonyaulax species can produce yessotoxins, which can accumulate in shellfish, no harmful effects to humans have been clearly demonstrated; however abalone mortalities have been related to blooms of Gonyaulax membranaceae.^[7]

Red tide

A Red tide is a discoloration of the sea water by pigmented cells like Gonyaulax spp., some of which may produce toxins. Gonyaulax spinifera has been connected to the production of yessotoxins (YTXs), a group of structurally related polyether toxins, which can accumulate in shellfish.^[8]