Penis Fencing Persian Carpet Flatworm

The Persian Carpet Flatworm - Pseudobiceros bedfordi are hermaphroditic and have two penises (can be seen in the picture as the two white pointed thing). During mating, they fence with one another, using their penises, attempting to stab and inject sperm in their opponent, while avoiding being fertilized by their opponent. They are able to inseminate their opponent by injecting their sperm into any region of the other's body they are able to penetrate. After successfully injecting the other, the spermatozoa stream through their partner's body on their way to ovaries, where they will fertilize the eggs. The stream is visible through the body tissue of the worm, appearing as pale streaks, like lightning jags.