Seasonal phytoplankton dynamics in extreme southern South America (Beagle Channel, Argentina)

► We analyzed phytoplankton dynamics during an annual cycle in the Beagle Channel. ► Very low cell densities and biomass concentrations were observed during autumn-winter. ► Highest biomass peaks were associated with Chaetoceros and Thalassiora spring blooms. ► A total of 138 taxa were identified, of which 10 are known as potentially toxic.