Feeding in the dinoflagellate Oxyrrhis marina: linking behaviour with mechanisms

Abstract Protists are major consumers of phytoplankton and bacterioplankton in the marine environment, playing a key role in carbon cycling and nutrient regeneration. Consequently, the feeding activities of planktonic protists have been intensively studied. In particular, the dinoflagellate, Oxyrrhis marina, has been used extensively as a model predator in laboratory-based feeding studies. This is predominately because it is easy to culture and manipulate but also because its plasticity in feeding behaviour allows it to represent a broad range of free-living heterotrophic protists. Prey preferences of this versatile, but selective, predator have been well documented. However, our ability to determine the factors driving prey selectivity is limited by a poor understanding of the detailed mechanisms underlying O. marina feeding. Within this study, we explore known aspects of O. marina feeding behaviour and highlight areas that require further research to exploit this species as an effective model protist predator.