Leopard Gecko Sexing
Leopard Gecko Sexing is not a very difficult task if you know what you are looking for. The largest mistake new enthusiasts make is that they attempt to sex a leopard gecko before the gecko is old enough. As a result, the female they believed they had ends up being a male.
Leopard geckos are sexually mature around 10 months of age and can be bred the following season if they are of the proper weight. (Please read our breeding section for more information on this.) Once the gecko has reached 5-6" in length, you can then reliably sex them. Unless you are experienced, sexing before the total length of the gecko reaches 5-6" is a gamble and may result in an inaccurate sexing.
When housing multiple leopard geckos together, it is crucial that you know the sex of the leopard geckos before they are placed together. Males will fight with one another over territory and this can result with both males being injured or killed.
Male Characteristics - Leopard Gecko Sexing
The physical characteristics of the male leopard gecko slightly differ from those of the female. When compared, male leopard geckos tend to be the heavier bodied sex. They also tend to have a broader head than the female. This method of sexing them however is completely unreliable.
To properly sex a male leopard gecko, there will be two unmistakable characteristics that stand out. The first will be the preanal pores found above the vent.
The preanal pores found on the male are used to excrete a wax-like substance that allows them to mark their territory. On occasion you may even witness the wax being excreted. The preanal pores will have small tubes everted through each opening. If you look closely, you will see that a wax-like substance is present. The image to the right show both the preanal pores of a male as well as the wax-like tubes that I am referring to.
Female Characteristics - Leopard Gecko Sexing
Females are define by their lack of male characteristics. Typically females are not as heavily bodied as males, though there are some females that are extremely large. They also typically have heads that are not as broad as the heads found on males. Again, there are occasions where the females physical appearance based on size would certainly indicate that it were a male. This is the very reason that the comparison of body mass and size is not a reliable method for sexing leopard geckos.
The actual sexing comes in the fact that female leopard geckos lack hemipenal bulges below the vent and their lack of preanal pores. Some females WILL have slightly noticeable preanal pores, but they are not nearly as prominent as they are in males. When sexing, look for both the hemipenal bulges as well as the preanal pores. If there are no hemipenal bulges, you have a female unless the leopard gecko simply was too young to sex accurately.
Leopard Gecko Temperature Sexing
If you are breeding leopard geckos, you have a wonderful tool at your disposal. Leopard geckos are capable of being incubated for sex. The first two - three weeks of a geckos incubation is when the animals sex will be defined. Based on the temperature in which you incubate, you can predetermine the sex of the leopard gecko with a 99% accuracy rating. This is often why you will see "temperature sexed male or female" when looking at various online breeder sites. This simply means the hatchling being sold was incubated for either male or female.
Temperature sexing is an invaluable tool for those working with leopard geckos to create new morphs and phases. Since males can not be housed together do to aggression, many breeders limit the number of males that they produce. This allows them to breed out harems of females that will hopefully have the genetic trait in which the breeder is attempting to work with or create. To learn more about how the genetics work, read our genetics section.
Females are easily produced when the incubator is set at a constant 79-81° for the first 3 weeks of incubation. At these temperatures you will yield 99.9% females. Following those 3 weeks, the incubation temperature should be raised to 88-90°.
Males are best produced at temperatures of 88-91°.
A mix of both males and females is best produced when the incubator is running at 85-87°.
The temperature in which you incubate at also plays a few other roles in the development of the embryo. Please read the breeding section for more information to learn how temperature affects the offspring.