Distribution of paralytic shellfish poison among Pyrrhophyta

Abstract

Using the mouse bioassay for paralytic shellfish poison (PSP), the distribution of toxicity among 23 dinoflagellate species was studied. Special consideration was given to red-tide-forming species and to those species previously implicated as causative organisms in paralytic shellfish poisoning. Among those investigated were ten marine species of the genus Gonyaulax, previously known to contain three toxic species. The presence of PSP was detected only in Gonyaulax species of the section Catenella. The amount of toxin varied in different species, ranging from 0.05 to 24 pg/cell. The amount of toxin per cell also varied with the phase of growth (exponential or stationary) in the New England red-tide species, G. tamarensis var. excavata Braarud.