Multiple plastid losses within photosynthetic stramenopiles revealed by comprehensive phylogenomics

Ochrophyta is a vast and morphologically diverse group of algae with complex plastids, including familiar taxa with fundamental ecological importance (diatoms or kelp), and a wealth of lesser-known and obscure organisms. We sequenced transcriptomes from 25 strategically selected representatives and used these data to build the most taxonomically comprehensive ochrophyte-centered phylogenomic supermatrix to date. We thus document, for the first time, plastid loss in two separate ochrophyte lineages. Altogether, our study provides a new framework for reconstructing trait evolution in ochrophytes and demonstrates that plastid loss is more common than previously thought.