Biofuels; Eustigmatos; Goniochloris; Monodopsis; Monodus; Nannochloropsis; Fatty acids; Trachydiscus; Vischeria

The Eustigmatophyceae is a class of yellow-green algae allied with the Chrysophyceae and other chlorophyll c possessing stramenopile (heterokont) algae. Some members of the class, especially the marine species of the genus Nannochloropsis, are under intense investigation for their potential for production of biofuels and beneficial fatty acids. The class has generally been thought to comprise a small number of genera and species, and these organisms were considered rare or infrequently encountered. In this study, we examined the phylogeny and diversity of this class by analysis of nuclear 18S rDNA sequence data. Our analysis included sequences from all the named members of the Eustigmatophyceae held in culture collections as well as a number of strains identified in culture collections as Xanthophyceae, new strains with features characteristic of the Eustigmatophyceae, and published data for uncultured DNA clones...