After mating, the male of tape snake seals the female genital pore with fluids from its kidneys. This seal is a sort of "chastity belt", preventing mating by other males and ensuring fertilization of the female by the first male.
Male of the Darwin's frog (frogs inhabiting the southern coast of Chile) swallows its eggs and holds them in its vocal sac after fertilization. When the tadpoles grow up, he opens his mouth and lets them out.
Sea horse is the only animal species, whose males become pregnant and give birth. During the breeding season the female seahorse swims up to the male and with nipple-like appendage introduce eggs in a special cell in the form of a bag on the abdomen of the male.Then the male fertilizes them and bears young seahorses in its stomach for some time.
Fertilization process of Mozambique catfish takes place in the female mouth.After laying eggs, she turns around to swallow them. And the spots on the anal fin of the male look very much like eggs. Confused female opens her mouth to swallow these eggs too, and then the male produces sperm fertilizing eggs that are already in the female's mouth. Babies develop there as long as they grow up. Even after small fish begin to search for food for themselves, at the slightest danger they rush to a secure location - the mouth of his mother.
The females of a bed bug do not have holes for mating, and males have to pierce holes with their sharp and curved penis. Then he introduces sperm into the female.
During mating, the female of praying mantis eats her partner. While the intercourse lasts, the female holds the male tightly and then begin to eat his head. Sexual desire of the male is so great that it does not stop mating, even when it is threatened. Some scientists believe that the process of eating of its head even enhances sexual desire of the male.
Male Acariformes are born fully formed insect and helps their mothers in childbirth, acting like a midwife.
The legs of the male water mite sometimes serve it as additional sexual organs, with which it penetrates the female. During mating it pushes the female to the ground with tiny hooks so much that it barely moves.
Eared marsupial mouse - similar to normal mice Australian marsupial, are unique among all mammals, they die after mating.
The male tick has no penis, and it penetrates the female genital opening with its nose.