Ketoacyl synthase (KS) domain phylogeny in dinoflagellates (modified from [81,122,129]). Phylogenetic tree representing the three sub-clades of KS domains within the dinoflagellate type I PKSs, multi-domain PKSs that cluster with other apicomplexans (condensed clade represented by 1), chlorophytes, haptophytes (condensed clade represented by 2) and the burA like PKS-NRPSs reported from dinoflagellates along with schematic representations of PKS domains represented by AT: acyl transferase, A: Non-Ribosomal Peptide Synthase, KS: ketosynthase, DH: dehydratase, KR: ketoreductase, TE: thioesterase, ACP: acyl carrier protein, ER: enoyl reductase, SL: 5’ splice leader, polyA: poly A tail. Other PKS groups are represented by 3: Modular type PKS cis AT clade, 4: fungal PKS non-reducing clade, 5: Animal type I FAS, 6: fugal PKS reducing; and 7: Type II PKSs.