snail darter

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun A small snail-eating darter (Percina tanasi) found only in Tennessee. A dam on the Little Tennessee River (completed in 1979) destroyed what had been the only known population of the fish, but it was later found in other locations.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun a small snail-eating perch of the Tennessee River