I remember watching "Man and Nature" on CCTV. There was a video showing that loaches can hide in the mud and survive for several years or even more than ten years when the weather is dry!

I also have the impression that after surviving for many years in a house made of mud, heavy rains activated the loaches. I can't find the resource either.

After my search later, I found out that it was indeed a lungfish. After it was made into mud bricks in Africa, it rained and activated it.

(But I remember that at that time, Man and Nature talked about loaches!)