Geyri's feel most at home at rough, rocky area's with hills and mountains, a desert landscape. They live in the central part of the Sahara. They live in the desert and half desert with great differences in day and night temperatires. The animals prefer rockcracks over caves and holes. During their wintersleep they stuff themselves between rocks.

The Geyri can reach up to 37 cm so it's an average sized uromastyx. It has different sized scales on it's head and body. It has pointy scales on it's ears and pyramid type scales on it's hind legs. The tail is about 20 to 23 segments and is fully scaled and pointy and can be sharp so be carefull. You have two colortypes when it comes to Geyri's, the red type (with somewhat orange sometimes) and the yellow type. The difference in color probably stems from a different chemical combination in the soil where the eggs have been laid. The difference between male and female can't really be seen before they reach adulthood and start to show their colors which is when they are around 3 to 5 years old. Females will have more brown/black coloring and are far less colorfull than the males who are mostly bright red or bright yellow. Some also look at the color of the belly, the belly of males are the same color as the rest of their body but not everyone agrees if this is a proper way to tell males and females apart.

As Geyri's are quite active they require a spacious enclosure of at least 1 m2. By making a backwall with levels using flagstones for example can create more space. It also simulates the cracks from their natural habitat. You can use sand or turf to cover the ground. Use different types of rocks (which must be put steady on the ground so ýour animals can't be caught under them) such as flagstones or use corque and wooden elements to decorate the cage. Also (fake) plants or cacti or broken pottery can brighten yp your cage. Geyri's feel more comfortable when they can hide so provide as many hoding places as you can.

Geyri's live in the desert and love the sun and to bask in it so you can never have too much light. To heat up the cage I use heat lamps and a UVB lamp. To create the right temperature you must use more than 1 lamp. The average day temperature should be around 30°C-32°C. Under the basking spot you can let it rise up to 55+°C and you can create another spot where it;s about 45°C. It's important the temperature varies in different places of the cafe. Some hiding places should be around 25°C to 29°C going up to 55+°C underneath the hottest lamp. A night temperature of 15 to 20°C will suffice so using extra heatproducts during the night is not needed. During the summer I leave the lights on for about 12 to 14 hours a day and when it's going towards the winter I gradually go to 8 hours a day for the wintersleep.

A must have in a Geyri cage is a UVB lamp. I use a 100W or 160W Megaray depending on the hight of the cage. The UVB light causes the Geyri to produce D3 which is very important for it's health.

I feed my Geyri a salad of greens in a daily bases. I mainly feed them enidive but also paksoi tauge several sorts of lettuce leek alfa-alfa grated carrot hawkbit grated pumpkin etc. I also offer a mixture of seeds and red lentil.

The level of humidity is low in the enclosure. One of the hiding places I keep a little moist to help shedding. In general the animals don’t drink from a bowl they extract the most of the needed moist out of their food. I offer water but this isn’t used many times by the animals. At night I remove the bowl so that the humidity level doesn’t rise.

Spinytailed lizards are sexually mature after about 3 or 4 years Uromastyx macfadyeni is the only exception on this rule this subspecies is sexually mature after 2 years.I have offered the animals a winter-rest of 2 months. Gradually I decrease the light hours from approximately 12-14 to 6 each week I decrease with 2 hours. When I reach the point of rest (6 hours) I hold this point for 3 weeks and then I steadily increase the hours of light (some to this abrupt but I have good results with this method). If the animals keep being active in the rest-period I also decrease the amount of watts in my lighting. It helps when temperatures outside drop to so that the animals get a low night temperature.

Most times after increasing the hours of light the Uromastyx show their mating-rituals. They first start by the males spinning in circles in the enclosure and on the female while doing this the male marks the enclosure and the female with a white substance. After this the male start head bobbing and chasing the female. If this is successful a typical lizard mating follows with the male delivering a firm neck bite to the female and the tails entangling. If a female isn’t prepared to mate she turns on her back the male usually stops pursuing the animal. Uromastyx carry the eggs on an average of 6 weeks. After this time the female has increased significantly in size and you can see huge bulges in the stomach-area. When the female lays the eggs it’s not hard to find them because she will dig viciously and remove all the sand to the nest. She also loses significant size and weight after the laying. With Uromastyx the female sometimes offers a certain kind of nest guarding which would suggest maternal care but I have never witnessed this. Only one female would stay in the vicinity of her nest but didn’t react when I removed the eggs.

Incubation of the eggs
Incubation of eggs of Uromastyx isn’t hard. There is only one important rule don’t incubate to wet. Success will be reached with a mixture of substrate and water of 2:1 (vermiculite/perlite:water). Temperature should be between 29 °C and 31 °C. The eggs will hatch after 90 to 120 days. Remarkable is that baby uro’s are very timid when they have just hatched it takes about 4 hours before the animals start walking around. For this reason is let the animals quite long in the incubator after hatching after 6 hours I put them in their rearing enclosure.

Juvenile Uromastyx are usually much less coloured than their parents. Other than that they behave the same as their parents and dig a lot. The animals can be raised for the first weeks in a group. After that they will start to threaten each other and they start to fight for dominance (not in all subspecies I witnessed this with Uromastyx acanthinura nigriventris). You can separate the dominant animals when necessary. It’s very funny to see a juvenile spiny tail that threatens you they start to dance shacking their behind. I feed the juveniles the same as the parents only I cut up the salad a little finer. I dust al their food with a supplement consisting of calcium and vitamins.

Spiny tailed lizards are very interesting animals to have. They have relatively simple desert-like enclosures. Uromasty are pretty active small lizards only sometimes they can be a bit sheer. However with the right amount of space the animals will let you observe them frequently. Spinytails are one of the most colourfull species of lizards and have very distinctive exterior features (like: colour a tortoise-like head and a spiny tail). An attractive and interesting animal in the herphobby.


• Uromastyx plus other common Agamids – Jerry G Walls – isbn 1882770870 – The herpetocultural library

• Spiny-tailed Agamids: Uromastyx and Xenagama – R D Bartlett – isbn< 0764125729 – Barron’s

• Uromastyx – Thomas Wilms – isbn 3936180121 – Herpeton

• Dornschwanzagamen – Thomas Wilms – isbn 3980621472 –Herpeton
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• Basic care of Uromastyx Lizards – Philippe De Vosjoil – Advanced vivarium systems

• AVS Uromastyx – Jerry G Walls – Bowtie Pr

• Uromastyx verzamelnummer, 2005 – Stichting Doelgroep Groene Leguanen

• Draco 31, Dornschwanzagamen – Draco

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