Is Your Crested Gecko Male Or Female? (Pores & Bulges Are Key)

Do you think your male crestie keeps lunging at you because it’s that time of the year? What if your crested gecko is actually female? Can you even tell the difference between the two?

The pores, bulges, and spurs near their tail base and the calcium sacs at the roof of their mouth differentiate male from female crested geckos. Male crested geckos have big pores, bulges, and spurs, but these are small or not present in females. Also, female crested geckos have big calcium sacs while males have small ones.

Unsure of whether you’ve got a little lady or not? Then try sexing your crested gecko at home. Get the hang of differentiating male and female cresties by reading on!

Sexing Male vs Female Crested Geckos (4 Signs!)

The sex of crested geckos can be identified once they reach 12–30 g at around 3–9 months old. Keepers can determine a crested gecko’s sex by inspecting its pores, tail base, spurs, and calcium sacs.

Just like the ever-popular leopard geckos, crested geckos are thought to also have temperature-dependent sex determination [1]. However, there isn’t much research done on this topic so many breeders actually just incubate them at room temperature.

Planning to hatch gecko eggs? Check our article on proper incubation!

However, other experts believe that they may have gene-based sex determination—a ZZ-male and ZW-female sex chromosome system. This could be why female cresties are capable of asexual reproduction called parthenogenesis.

But fret not—you don’t need a background in zoology or herpetology for you to be able to tell apart male and females crested geckos!

Like leopard geckos, it’s fairly easy to sex cresties too, even more so since you can check for all 4 of their secondary sex features!

1. Femoral Pores

The average male crested gecko has 1–2 U-shaped rows of enlarged femoral pores with waxy secretions. By contrast, a female crested gecko will either have undefined femoral pores or none.

As its common names suggest a crested gecko’s preanal or femoral can be found above its vent slit, extending to either side of its inner thighs [2]. More often than not, you might be told that it’s impossible for female cresties to have femoral pores. However, don’t be fooled!

Even female crested geckos can have femoral pores. However, unlike the preanal pores of males, theirs are much less distinct.

Furthermore, male cresties will have waxy cream-yellow plugs sticking from the middle of each femoral pore. These are believed to help them mark their territory among other things. But their overall purpose is still not fully understood.

But it’s also possible for a male lizard’s femoral pores to shrink in the event that they are castrated [3].

Regardless, you will need an illuminated jewelry loupe (here on Amazon) to clearly inspect these precious little geckos’ pores.

2. Tail Base

Male crested geckos generally have pronounced round hemipenal bulges. However, female crested geckos will have a relatively flat triangular tail base.

A male crestie has two penis kept hidden inside pouches they have in their vents. These are called hemipenes.

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Cresties rarely pop out their hemipenes since they only need to use them for mating or to get rid of retained sperm plugs. Because of this, their tail base may look swollen. This round hump with a slight indentation in the middle is called the hemipenal bulge.

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Even when viewed from the side, most male crested geckos have prominent hemipenal bulges. In comparison, females have pretty flat triangle tail bases.

From time to time though, I come across female crested geckos that develop a slight bump on their otherwise smooth tail bases. This commonly happens when the female puts on a lot of weight.

3. Spurs

Normally, male crested geckos have little while spikes, called spurs, on either side of their tail base by the top of their bulges. Female crested geckos, however, have slightly smaller spurs.

Not all geckos have spurs. For the species that do, keepers sometimes mistake these typically white pointy structures for dried-up semen. So the idea that only male geckos have spurs below their vents spread.

But the truth of the matter is that female crested geckos also have spurs. They aren’t always white either. Depending on your crestie’s morph, its spurs could also be cream, yellow, or orange.

Spurs are just scales that are commonly twice as big as the rest of the gecko’s regular scales within the area below its vent.

Frankly, though, I don’t know what its purpose is. Cloacal spurs aren’t familiar to many people, including experienced keepers. They also don’t seem to be a popular research topic.

As such, they aren’t a reliable factor to check for sex determination. You should never base your crestie’s sex on their spurs alone.

4. Calcium Sacs

Small calcium sacs are distinctive in male crested geckos, while prominent calcium sacs are conventionally found in female crested geckos.

To check their chalk sacs, you need to get your crested gecko to open its mouth to check the size. Securely hold them in your hands and rub their lower jaws to get them to open up.

Just be careful not to hold them too tightly and don’t put your fingers in their mouths because they might bite.

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A chalk sac—or, more accurately, an endolymphatic sac filled with liquid calcium—is usually larger in female crested geckos than it is in males.

Each crested gecko has two endolymphatic sacs on either side of the roof of its mouth, near its ears. Sometimes, this can extend to either side of their necks [4]. Many reptile experts believe that a gecko’s chalk sac serves multiple functions.

Gecko calcium sacs are believed to have a role in:

Regulating ear pressure

Transmitting sound waves
Protecting the brain and nerves
Storing calcium reserves

Assisting bone formation
Producing eggs

Despite not being fully proven by studies, the latter purposes justify why many people think that female crested geckos, especially gravid ones, have round and prominent calcium sacs.

Nevertheless, it’s important to remember that the calcium geckos get from their diet greatly affects the size of their endolymphatic sacs.

In other words, female cresties can have small sacs due to calcium deficiency, whereas male cresties can develop abnormally big sacs due to too much calcium

Further Questions

Is it true that only male geckos make sounds?

Contrary to popular belief, male geckos aren’t the only ones able to make a sound. Both female and male geckos can become noisy for reasons such as warning and mating. However, different gecko species may have varying vocalizations that can have different meanings.

What should you do if you can’t determine your gecko’s sex?

Whether owners can’t determine or want to double-check their gecko’s sex, they can have an experienced exotic veterinarian do it. Clinical options for reptile sex determination include illumination, manual eversion, probing, and radiography.

Summary of Is Your Crested Gecko Male or Female

Male crested geckos can be identified by their prominent femoral pores, tail base with hemipenal bulges, and large cloacal spurs. But they have very small calcium sacs.

Female crested geckos, in contrast, have prominent calcium sacs. However, their pores, spurs, and fat bulge at the tail base can be very subtle or non-existent.