Ancoracysta twista was first described in November 2017 in Current Biology. It was found in a sample collected from the surface of a tropical aquarium brain coral. It actively feeds on Procryptobia sorokini, probably immobilising its prey through discharging a previously unknown type of extrusome named an ancoracyst.
Genetic analysis shows that it is not closely related to any known lineage, but it may be most closely related to a grouping of haptophytes and centrohelids. It is notable for having a gene-rich mitochondrial genome, the largest known outside the jakobids or Diphylleia rotans. Uniquely, it appears to contain both the nucleus-encoded holocytochrome c synthase system III and the mitochondrion-encoded bacterial cytochrome c maturation system I.