The Reproductive System of a Male Leopard Gecko

Leopard geckos have in recent years enjoyed a rise in popularity as household pets. "Leos" are generally docile, do not require excessive space or care, and are quite easy to breed, if the owner is inclined. Even if the owner has no plans to breed his leo, it is a good idea for him to learn as much as possible about his pet as a part of the leo's overall health care. The health of a male leo's reproductive system impacts both the breeding process as well as the leo's general well-being.

  1. External Anatomy/Sexing

    • In determining the sex of a leopard gecko, the most accurate results will be achieved when the gecko is at least six months of age; results are even more reliable as the leo approaches its first birthday. The most readily identifiable feature is the v-shaped line of pores under the rear legs at the base of the belly, just above where the tail meets the body. Also known as "vents", these raised pores are present in females, but appear larger and more distinctive in males. In addition, males also exhibit a pair of bulges just below the perianal pore line; these bulges hold the hemipenes, which are absent in the female.

    Internal Anatomy

    • Leopard geckos, like many other members of the reptile family, posses a pair of hemipenes, which are the reptilian equivalent of the penis. Hemipenes reside inside the gecko's body and protrude as necessary for mating. Only one of the pair is used in intercourse, never two hemipenes at the same time. The testes, which produce the sperm that is deposited into the female during intercourse, also reside internally.

    Intercourse

    • Intercourse between leopard geckos begins when the male approaches a female with his tail twitching; he then proceeds to bite her along the back of her neck. If she is receptive to him, she will move her tail to the side so the male can lie atop her. The male then lines up his vents with hers, inserts one of his hemipenes into the female's cloaca and discharges his sperm.

    Breeding

    • For male leopard geckos, the breeding guidelines are quite straightforward. Males should be roughly one year of age to be successfully bred. This is considerably younger than females, which should be closer to two years old; this helps ensure she has the stamina to endure the breeding process. To breed a male leo, he should be introduced to the female's territory to facilitate intercourse and left with her for up to two weeks. He should be removed to a different cage once the owner is confident that mating has taken place since he may damage the eggs after the female has laid them.

    Considerations

    • The most common problem afflicting the reproductive system of male leos is hemipenal prolapse, which occurs when one or both of the gecko's hemipenes project from his body and are unable to be retracted. This condition requires assistance from a veterinarian or an experienced reptile handler and can be fatal to the leo if left untreated.

      Leopard geckos are one of the reptile breeds that are temperature sex dependent, which means the gender of the hatchlings is dependent upon the temperature at which the eggs incubate.Eggs held at higher temperatures (above 88 degrees F) produce more males, while eggs held at cooler temperatures (80 to 86 degrees F) produce females.