Alexandrium minutum
Diagnosis
Armoured marine planktonic dinoflagellate. Cells are small, nearly spherical to ellipsoidal, somewhat dorsoventrally flattened and occasionally longer than wide. This species is widely associated with toxic blooms in coastal regions. Cells are sinlge with a characteristic ventral pore on the first apical plate 1'. Thecal plates thin. Thecal surface ornementation can vary from light to heavy reticulation (mostly confined to the hypotheca) with small scatterred pores. Intercalary bands are present. Large range in size : 15-30 µm in length and 13-24 µm in transdiameter width. Po, 4', 6'', 6c, 10s, 5''', 2''''. The epitheca is larger than the hypotheca. The apical pore complex (APC) is oval to broadly triangular and pointed posteriorly. The apical pore plate (Po) is large, narrow and oval with a wide comma-shaped foramen. The Po can be either in direct contact with the first apical plate (1'), or indirectly connected via a thin suture (thread-like process). A characteristic ventral pore is located on the slender and rhomboidal 1' plate. the distinctive sixth precingular plate (6'') is long and narrow. Associated with paralytic shellfish poisoning (PSP) events in coastal regions around the world. produce dense reddish-brown red tides. Toxin: GTX1, GTX2, GTX3 and GTX4 (Oshima et al. 1989)
Body_length: 15-30 µm
Body_width: 13-24 µm
Type species
Alexandrium minutum is the type species for this genus
Type illustration / Type locality / Type specimen
Type locality: Mediterranean Sea, Alexandria Haror, Egypt.
Ecology
Substrate: planktonic
Sociability: solitary
Salinity: marine
Salinity: variable (estuary)
pH: neutral
Feeding: Photosynthetic
Life cycle
Phases_alternance: haplontic
Generation: <1 month
Reproduction_mode: asexual_binary
Reproduction_mode: sexual_heterothallic
Resting_stage: cysts_sexual
Resting_stage: cysts_asexual