How to Square Microbial life in Solar Salterns

Microbial communities in hypersaline crystallizer ponds are amongst one of the best studied microbial ecosystems. Investigation of these extreme environments followed the scientific and technological developments in the past 50 + years ranging from the initial microscopy observations up to state-of-the-art molecular tools that have now become common practice. The hypersaline ecosystems are dominated by halophilic archaea but essentially contain members of all domains of life including viruses. One of the intriguing discoveries concerned the enigmatic square archaeon Haloquadratum walsbyi that initially resisted isolation for almost 25 years but was finally obtained into pure culture. In this short presentation I will focus on this specific isolate and its presence in its natural environment at the time of sampling.