Adult head lice mate right after they have finished the final cast of skin. The males try to mate with every head louse of a suitable size regardless of the other head louse being adult females, well-developed nymphs in the third stage or other males. The actual mating takes a relatively long time – sometimes up to 30 minutes or more. After the mating, both the male and the female must participate actively to separate from each other. Should one of them die during the mating, they will be stuck together forever.
Head lice mating
… and mating