sp. nov., a cryptic diatom species from the highly alkaline Van Lake (Turkey).

In this article we describe sp. nov., an example of a diatom species inhabiting extreme habitats. The new species has been isolated and successfully grown from the highly alkaline Van Lake in East Turkey. The description is based on morphology (light and scanning electron microscopy), the sequencing of its organellar genomes and several molecular phylogenies. This species could easily be overlooked because of its extreme similarity to but molecular phylogenies indicate that they are only distantly related. Furthermore, molecular data suggest that may occur in several alkaline lakes of Asia Minor and Siberia, but was previously misidentified as . It also revealed the very close genetic proximity between and the endosymbiont of the dinotom , providing additional clues on what might have been the original species of diatoms to enter symbiosis.