[3] These organisms have been found in the west coast of North America, Japan, Australia, and parts of South Africa.

[5] The resting cysts germinate once environmental conditions, mainly sustained warmer temperatures, are favorable, and will produce motile cells capable of photosynthesis and asexual reproduction, which form the blooms associated with paralytic shellfish poisoning (PSP).

[7] By ingesting saxitoxin, humans can suffer from numbness, ataxia, incoherence, and in extreme cases respiratory paralysis and death.

Shellfish poisoning affected over a hundred humans, and now saxitoxin is recognized as one of the most deadly algal toxins.

The optimal growth conditions for A. catenella include a cool temperature of around 17 to 23 °C, a medium to light illumination of 3500 to 4000 lux, and a high salinity of around 26 to 32 percent.