Literature-based records of phytoplankton taxa reported from South African coastal waters across the Benguela and Agulhas current systems.

This dataset is a literature-based compilation of phytoplankton taxa reported from southern African coastal and offshore waters, spanning the Benguela and Agulhas Current systems. It contains 229 records of 147 distinct taxa, compiled from 16 published studies (1987 – 2021) covering the west, south and east coasts of South Africa (including KwaZulu-Natal), Namibia and the adjacent South Atlantic Ocean. Each record represents one reported occurrence of a taxon and includes the regional coast, sampling location, oceanographic region, sampling depth (where reported), phytoplankton group, reported taxon, additional context from the source, and the original reference. Diatoms (135 records; 80 taxa) and dinoflagellates (69 records; 50 taxa) dominate the compilation, followed by haptophytes, prasinophytes, cyanobacteria and other groups. Taxa not identified to genus or species level in the source studies were retained. The dataset was compiled to identify locally occurring phytoplankton taxa against which experimentally derived toxicity thresholds can be compared, and can support taxon selection for future toxicity testing and monitoring in southern African waters. The number of records per taxon reflects how often a taxon was reported in the literature, which depends on sampling effort and taxonomic resolution, and should not be interpreted as abundance.