Wa Wa Yu is apparently the Chinese name for it, meaning "baby fish"
The Chinese giant salamander.
I had been told about the wa wa by a friend of mine from Tulsa who had lived for a while in Taiwan, and then of a Japanese analog sometime later by another friend. And I had also read of the animal in a zoology book a while before, noting the possibility of a (now extinct) North American version to validate various questionable reported sightings.
But, I had not known specifically that the wa wa was the same animal, and the reason I say "wa wa" instead of "wa wa yu" is that's what my friend called it, and he claimed "wa wa" was a mimicry of an infant's crying, which I suppose might make sense. Chinese words seem to be derived. But my friend also claimed he was told the wa wa made that sound, which I don't see otherwise reported. Perhaps, though, perhaps...