DiversityPyrenoids are found in almost all algal lineages,[1] irrespective of whether the chloroplast was inherited from a single endosymbiotic event (e.g. green and red algae, but not in Glaucophytes) or multiple endosymbiotic events (diatoms, dinoflagellates, coccolithophores, cryptophytes, Chlorarachniophytes, and Euglenozoa. Some algal groups, however, lack pyrenoids altogether: higher red algae and extremophile red algae, the green alga genus Chloromonas, and golden algae. Pyrenoids are usually considered to be poor taxonomic markers and may have evolved independently many times.[35]