Water provides a refuge from temperature extremes.
For fish out of water, death is usually inevitable but for lung fish, they have certain adaptations to ensure their survival in hot surroundings. Their swim bladder forms a crude lump, allowing them to directly take in oxygen from the surrounding air and then they escape the heat by burrowing.
The lung fish first swallow the mud to excavate chamber and passes out through the gills. then coats itself in mucus. when mucus dries, it forms a body bag that seals off the fish from the drought. As conditions worsen, the lung fish shut down to wait for conditions to improve. When drought finally ends, rainwater releases it from suspended animation.
In other parts of the world where there are dry conditions as well, the desert frog also has adaptations to help it live. It can survive untombed for years as the layers of skin that forms on it a water proof barrier prevents the frog from drying out.
Another example will be the tawny devil which can survive for years without drinking water. It simply eats black ants and this is sufficient in providing all the moisture it needs.
In addition, it can collect water through capillary action. Its skin sucks out the liquid like blotting paper from the ground. For example, when humans need water, they can drink from the bladder of the desert frog and what little water is wasted when drinking will then be absorbed by the tawny devil. The darkening vein traces the network of channels which directs the water to the mouth of the tawny devil. Morning dew is also drunk this way.