Yeah, cryptobiotic crust! I've seen it in the Sonoran desert. It doesn't look like much, I think if I hadn't been warned ahead of time not to step on it I might have just done it without thinking. Given that just footprints can take on the order of decades to heal I think a dune buggy ban makes sense in areas where it grows.

I'm still surprised to learn about the microbes in the Atacama: it's the driest place on earth, and I would have expected the salt deposits to make it even harder for anything to live there. Yknow what they say I guess: "Life, uh, finds a way."