Biological interactions of the five genera in the dinoflagellate family Kareniaceae with prey and protistan predators

Species and genera in the dinoflagellate family Kareniaceae have attracted the attention of scientists, aquaculture farmers, and government officials because many species in this family cause harmful algal blooms associated with the mortality of vertebrates and invertebrates. In addition, the genera in Kareniaceae exhibit different morphological, biochemical, and genetic characteristics. To understand bloom dynamics and eco-evolutionary strategies of the genera in Kareniaceae, the biological interactions of kareniacean species and genera with prey and predators should be explored. In the present study, we reviewed the trophic modes, prey taxa and size spectra, feeding mechanisms, growth and ingestion rates, and protistan predators of five genera Gertia, Karenia, Karlodinium, Shimiella, and Takayama in the family. Additionally, we explored the feeding occurrence in Gertia stigmatica, the prey spectrum of Karenia brevis, and the predation of Takayama tasmanica by heterotrophic protists, which have not been fully investigated prior to the present study. Karenia, Karlodinium, Shimiella, and Takayama have different prey taxa and size spectra. Furthermore, within the same genus, different species exhibit different biological interactions with prey and protistan predators, creating different ecological niches. This study provides insights into the eco-evolutionary strategies of kareniacean dinoflagellates.