Iv'e never had such a shock.

Many egg laying cichlids will attack, but they don't usually hurt because their crushing teeth are deep inside their throat. I won't try that with pirahna though!

Mbuna has sharp teeth on their lips and they can hurt, but mouth brooder don't have a permanent nest to protect and they rarely ever attack human hand.
 
I had just put a feeder in the tank of our newly aquired Red Oscars. I had one hand resting on the side of the tank lid, with my fingers sitting above the open water (I hadn't shut the lid yet). I was talking to my husband watching the fish. Next thing I knew, the male jumped up and grabbed my middle finger. It didn't hurt, but man, the shock of it. I could feel his mouth on the finger for quite some time too! It cracked me up.
 
Also, we now have a Jaguar Cichlid. He is the meanest fish I've ever seen. The whole time my husband and I were cleaning our tank, he was attacking his hand, the algea sponge and the vaccuum. When I was trying to get the filter tube from the bottom of the tank, he went right after me!!

I told my husband, it's his job to clean the tank now!
 
when rams attack...... heh.

gotta watch those jags, if he is bigger than a juvi he will have teeth!
 
all guapotes have psuedo canines they use them to hold prey in thier mouth.

http://www.aquariacentral.com/forums/showthread.php?s=&threadid=14684

if you look at the first shot of the female in this thread, (third pic) you can see what I believe to be the tops of her teeth. I dont know if thats what they are or not for sure but i know that they do have teeth.
 
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