Microplankton, comprising both phyto- and zooplankton in the 20-200μm size range, are a diverse and ecologically significant group. They form the foundation of the food web, are instrumental in carbon and nutrient cycling, generate at least 50% of global oxygen and facilitate the transfer of energy to higher trophic levels. Although microplankton occur throughout the world's oceans, their diversity and abundance varies spatially and temporally. Due to their high sensitivity and rapid response to changes in the environment, their biomass and diversity are considered Essential Ocean Variables (EOV's) for routine and sustained long term observations to assess global ocean changes. This dataset forms part of the routine monitoring along the west coast of South Africa under the Integrated Ecosystem Programme: Southern Benguela, which occurs biannually in February and August. This resource contains raw image data for May 2018 obtained from water samples processed using a FlowCam VS3...