Mikesgotone got the one I put out there. This rock bar is under water during high/normal water levels. You will bang into it, because it's only about a foot under. We call it Skunk Rock, because it has white stripes running across it. I've met lots of people that have lost lower units on it. I don't think it is marked on any maps either.
LundAngler, got the next one put up by Paul.
Here is another one,