I think the evidence is high that existing higher plant photosynthesis (Photosystem I + Photosystem II) is a merger of purple photosynthesis with Chloroflexus p

I think the evidence is high that existing higher plant photosynthesis (Photosystem I + Photosystem II) is a merger of purple photosynthesis with Chloroflexus photosystem (possibly via horizontal transfer). IIRC Photosystem I is derived from purple, and PS 2 is derived from chloroflexus.