Abstract: This invention concerns microorganisms, to be precise Archaea, which, in case of cultivation at 25° C., indicate unsaturated ether lipids in quantities of at least 10% with reference to the total amount of ether lipids. In a further aspect, this invention is directed towards microorganisms within the Archaea, in particular from those of the class halomebacteria, in particular the order of Halobacteriales, in particular the family Halobacteriaceae, in particular the genus Haloarcula and Haloferax containing lipid compositions. These lipid compositions, in particular liposomes, are characterized by the presence of large quantities of unsaturated ether lipids. In a further aspect, the existing invention concerns a process for the extraction of these unsaturated ether lipids from the designated Archaea.