Pseudo-nitzschia is a widespread genus of marine pennate diatoms comprising 58 species of which 28 can produce the neurotoxin domoic acid, causative of Amnesic Shellfish Poisoning (ASP). Species of the genus are found in both oceanic and coastal waters where they can form large blooms. The timing and magnitude of blooms is generally described based on water samples collected at the surface, while limited information is availab...