thunderfish

from The Century Dictionary.

• noun The electric catfish of the Nile, Malapterurus electricus, which is capable of giving shocks like the electric eel and electric ray. Also known by its Arabian name raasch. See cut under Malapterurus.
• noun A European cyprinoid, Misgurnus fossilis: apparently so called as forced out of the mud, in which it habitually burrows, by a thunder-shower. See misgurn.

from the GNU version of the Collaborative International Dictionary of English.

• noun (Zoöl.) A large European loach (Misgurnus fossilis).