Coccomyxa subellipsoidea, a unicellular green microalga, surviving in harsh environments like polar regions and deserts. This eukaryotic organism, with an ellipsoidal to oval shape and 3-10 μm size, has a single chloroplast and no rigid cell wall, reproducing through autosporulation. Its capacity to endure desiccation and freezing makes it valuable in biotechnology, offering versatility for applications in food, biofuels, and as a cold adaptation research model.