To go back with what Azelor said, I wonder if a gigantic and deep crevasse in the desert would allow hidden streams of water and underground lakes to survive depsite the dry scorching heat. However, if we have such a landscape, what kind of ecosysteme would we find? I wouldn't see mushrooms, maybe some shade bushes and lots of giant insects would make it a plausible option. I wish I had lots of knowledge about those stuffs but sadly I don't and I will admit I may be a little ''buzy & lazy''. If I inspire myself from Terraria, I would see giant ants and desert worm-like creatures living underground and maybe they would be both an essential to maintain the ecosystem healthy by providing numerous grottos and tunnels in which water and vegetation could grow out of the sun's scorching rays. That being said, I would maybe have most of the animals and bugs being nocturnal so they are most active when it is most cool. One thing which could be interesting would be to have giant aloes types of plants, succulants. The lack of light would also make it a quite hostile and dangerous environment for humans even though they could bring torches. Last thing we want is to run out of fuel and then oops pitch black and dangerous pits all around. Also, with ants and worms, I would also imagine the fissure having quite the labyrinth.