Potentially toxic species of the diatom genus Pseudo-nitzschia in Argentinian coastal waters

A taxonomic study of potentially toxic Pseudo-nitzschia species present in Argentinian coastal waters was carried out using light and scanning electron microscopy. Pseudo-nitzschia australis Frenguelli, P. multiseries (Hasle) Hasle, P. pungens (Grunow) Hasle and P. pseudodelicatissima (Hasle) Hasle were found and their temporal and spatial distribution along the Buenos Aires coast line is described. Pseudo-nitzschia pseudodelicatissima is reported for the first time for Argentina. The species Pseudo-nitzschia delicatissima (Cleve) Heiden and P. seriata (Cleve) Peragallo, which had been previously recorded for the country, and whose identification is likely to have been erroneous, were not found during this study. Although the other four species identified have been reported to produce domoic acid, no toxic events have been noted in samples from the Argentinian coast.