It was. And when they were first found about five hundred years ago they were thought to be baby dragons.
After the white olms also the black kind was found in Slovenia, called simply črna človeška ribica or Black human fish (Proteus Anguinus Parkelj). Parkelj is an old Slovenian word for the devil.
Damn, I'm good. And my being Slovenian has absolutely nothing to do with it.