The Ebridea is a group of phagotrophic flagellate protist present in marine coastal plankton communities worldwide. Ebria tripartita is one of two (possibly four) described extant species in the Ebridea.
Members of this group are named for their idiosyncratic method of movement (ebrius, "drunk").
Ebriids are usually encountered in low abundance and have a peculiar combination of ultrastructural characters including a large nucleus with permanently condensed chromosomes and an internal skeleton composed of siliceous rods.
The taxonomic history of the group has been tumultuous and has included a variety of affiliations, such as silicoflagellates, dinoflagellates, 'radiolarians' and 'neomonads'. Recently the Ebridea is treated as a eukaryotic taxon with an unclear phylogenetic position, but last molecular studies (Canadian Institute for Advanced Research) place of ebriids within the Cercozoa.