While spots on your leopard gecko’s back and legs are normal, if you ever notice a dark spot on their belly, that could be more of a cause for concern. If you are already or plan on becoming a leopard gecko owner, it would be a good idea to become well versed in the possible causes, treatments, and preventions of the conditions that could cause dark spots on a gecko’s underside.
Healthy Leos should have a reasonably plump and round disposition, and stomachs should be rounded and full but not distended. Females carrying eggs, also referred to as gravid, will have slightly distended stomachs. This will usually occur around 18-24 months of age, and the belly could be swollen and firm but will likely be lacking any concerning dark spots.
There are five common causes of black or dark spots on your gecko’s underside. Discussed below are each cause, their symptoms, and how they could be caused in the first place. These are in order of least concerning to most concerning and needing immediate vet attention.
Could be Totally Normal
Leopard Geckos are known to have smooth and almost translucent skin. Because of the nature of their skin type, it is possible that a dark spot on their belly could be normal.
It could simply be an indication that your gecko has food in its intestines. As long as their stool passes normally, they are eating and drinking well, and their temperament seems normal, there may be no reason for concern. Keeping a close eye on the dark spot and your gecko’s behaviors, making sure there are no other causes for alarm would be fine in this circumstance.
Caused by Stress
Dark spots can also be associated with stress in a leopard gecko’s environment. Some geckos can be stressed by incorrect handling, incorrect temperatures, and humidity levels, or can be stressed out by having more than one gecko in one enclosure.
Males should never be placed in the same tank together, and females should never be placed in the same tank together as it can lead to bullying and stressful conflicts. You will usually know that your gecko is stressed out by noticing their behavior.
Your Leo may be stressed if they are exhibiting the following behaviors:
- Not Eating
- Aggressive or skittish behavior during handling
- Irregular bowel movements
- Vocalizations (most commonly will sound like chirping or squeaking)
- Glass Surfing (Trying to climb the side of its enclosure. )
- Tail Wagging
- Hiding for extended periods
Keeping your gecko’s stress levels to a minimum is vital to its overall well-being and health. At least a 20-gallon tank is essential.
Always maintain between 75-85 degrees Fahrenheit in their tanks with a heat basking area of 90-95 degrees Fahrenheit at the most. Leopard Geckos need less moisture in the air and ideally should have between 30% and 40% humidity in open spaces. Make sure to provide them with plenty of hiding spaces, which will require a higher humidity level between 70%-80%, as this will help with shedding.
The next three causes are considered relatively severe, and if you suspect any of these conditions, you should seek help and treatment from your exotic vet as quickly as possible.
Parasites are another possible cause of dark spots on your gecko’s belly. Parasites can be caused by your Leo interacting with an infected gecko or if they are not being fed poor quality food.
The most common leopard gecko parasites are pinworms and coccidia. In healthy geckos, they can go relatively unnoticed, but high levels of stress can weaken your gecko’s immune system significantly enough to where they can become a severe problem.
Symptoms of parasitic infection can be:
- Drastic weight loss. Pay attention to the size of your gecko’s tail. This is where they store a good amount of their fat content, so you will most likely notice weight loss there first before anywhere else.
- Loss of appetite
- Particularly smelly stool
- Dark spot on the underside of their belly
Keep in mind that parasitic infection can only be confirmed by stool sample testing. You would need to collect a fecal sample and bring it to your vet, who will then test for the presence of parasites.
A gut impaction can be pretty common, especially in young geckos. Leopard geckos “smell” the environment with their tongue, so if an inappropriate substrate is provided (such as bark or wood shavings), your gecko will be more prone to becoming impacted.
Other causes can be giving live feed that is too big for your animal to handle, feeding with a live feed that is harder to digest, dehydration, or parasites. Symptoms to look for are:
- Cloaca Licking (the slit opening underneath their tail)
- Loss of Appetite
- Dark spot on the underside of the belly
- Weight loss (Again, pay attention to their tail mass)
Constipation will likely be your first sign that you are looking at some type of impaction. Cleaning your tank regularly will allow you to keep track of bathroom habits for your gecko.
This is by far the most severe condition listed here, and if you ever suspect that your gecko is internally bleeding, please seek medical attention as quickly as possible. Many different things can cause internal bleeding, and not all causes are known.
It seems to be most commonly caused by the gecko being mishandled or dropped. If an impaction goes for a while without medical attention, it can also progress into internal bleeding.
Signs of internal bleeding are as follows:
- Dark spot on the underside of their belly
- A white tongue
- Defecating dark blood
- Loss of appetite
- Not drinking
If you ever notice a dark spot on Leo’s stomach, your course of action will largely depend on the source of said dark spot. If you suspect that the cause stems from stress, pay attention to the husbandry and fix any environmental factors that could cause the anxiety.
A parasitic infection will need to be confirmed by your exotic vet, and you will need to follow their treatment plan CAREFULLY. Incorrect dosing of any parasitic treatment can be catastrophic and result in death, so please follow your vet’s directions to a T.
If you suspect impaction, you can start with giving your gecko a warm bath to help soothe its intestines and make the passing of the impaction easier. Give its belly a gentle massage while in warm water to provide extra help if needed.
If the blockage does not pass, make an appointment with your exotic vet to help further. Lastly, if you suspect any internal bleeding, contact your vet immediately, as your gecko will probably be in a lot of pain.
Out of all of the more serious conditions listed in this article, impaction is probably the most common. As mentioned, it can be caused by improper substrate being used in their tanks or by improper feeding.
The best form of treatment for impaction is always going to be prevention. Be sure that you are well educated on the types of substrate to use, what kinds of live insects to feed with, and be mindful of the size of those insects you are providing. A good rule of thumb is to always feed insects about the size of the space between your gecko’s eyes.
Research shows that a Bioactive substrate consisting of several layers of gravel, soil, and clay mixtures is the best type of substrate for a leopard gecko. This type will replicate their natural environment more closely than any other type of substrate. Contrary to popular belief, sand, coconut fiber, and wood chip substrates are likely to cause impactions if your gecko decides to eat a few mouthfuls.
While dark spots can be alarming, there are several reasons why they could exist on your leopard gecko’s belly. The good news is that with proper handling, husbandry, and feeding habits, all of these conditions are almost entirely avoidable. As always, if you are questioning your pet’s health, don’t hesitate to get in touch with your exotic vet first before experimenting with any type of treatment.