That does not exclude males with an average-sized sex organ, called a gonopodium. These fish out-compete the larger-endowed males in a predator-laden environment because they have a faster burst ...

They don’t have a penis, as such. Instead, they have modified a fin into a penetrating organ called a gonopodium. These penis-ish organs are tipped with an unpleasant set of claws, hooks ridges ...