Clearly, this single celled, is performing computation. 'Knowledge' of self, environment and the relationship between the two worlds has to be encoded in an active and dynamic fashion. While networks and networks of cells are an incredible and fascinating system, clearly inspirational and massively insightful for the development of intelligence outside of biological systems, one could and should consider the argument that by jumping to networks as systems for computational intelligence, we skipped a step in describing how cells (and thereby networks of cells) encode computation and intelligence. I think that a major step in theories of intelligence and mind could be possible by reconsidering intelligence at a cellular and single cell level.
https://en.wikipedia.org/wiki/Dinoflagellate https://en.wikipedia.org/wiki/Kleptoplasty https://aem.asm.org/content/78/3/813