Pleopsidium chlorophanum

Pleopsidium chlorophanum (gold cobblestone lichen): 27  is a distinctively colored, bright lemon-yellow to chartreuse crustose lichen, which favors dry arctic or alpine sandstone cliffs and boulders. It is a rare alpine lichen in Europe. It is in the genus Pleopsidium of the family Acarosporaceae. This lichen is one of the few species able to survive at high altitudes in Antarctica, at altitudes of up to 2,000 metres (6,600 ft). It is able to cope with high UV, low temperatures and dryness. In its Antarctic habitat, it can be found on the surface, but it is mainly found in cracks, where just a small amount of scattered light reaches it. This is probably an adaptive behaviour to protect it from UV light and desiccation. It remains metabolically active in temperatures down to −20 °C (−4 °F), and can absorb small amounts of liquid water in an environment with ice and snow. It is of especial interest for astrobiology since this is one of the most Mars-like environments on the Earth. In a ......read more on Wikipedia.