a lion will never sting somthing unless it has to in defense
The poisonous fins are the ones that are not webbed
But it shouldnt matter... just dont mess with em and you dont have to worry bout their venom
the lions defense is the spine fins mainly in a defense mode they will raise the fins or if erritated or threatened will lunge toward his intended target.I have a large vol in my agressive he was housed with a pesky niger trigger he finally got fed up tying to feed and attacke the niger in less than 10 min the trigger was done for.if a lion feels invaded he will also attack the hand that feeds them be careful.and few fish survive the sting of an adult lion