Algal researchers nominated the Blue-Green Rock Dweller Chroococcidiopsis for the alga of the year 2017. The single celled organism lives inside rocks and lichens, survives extreme climatic conditions and makes hostile environments accessible – today and most likely thousands of millions of years ago as well. While doing so, it paved the way for plants and animals. The blue-green rock dweller, belonging to the cyanobacteria lives like all algae, from sunlight, and is of great interest to ecologists, biotechnologists, and desert- and space researchers. It is the favorite research subject of Prof. Dr. Burkhard Büdel from the University of Kaiserslautern, who has been investigating it for more than 30 years. He is a member of the Phycology Section of the German Society for Plant Sciences, in which the algal researches are organized and who nominate this year an alga of the year for the tenth time this year.