Added 1 November 2003. Last updated 30 June 2022: removed U. asmussi, U. hardwicki and U. loricata to their own genus, Saara, and updated the Bibiography.

A look at the Family Agamidae

Uromastyx

Uromastyx, Mastigures, Dab Lizards, Spiny-Tailed Agamids



Uromastyx are a medium-sized genus of agamids found in a narrow but long range from North Africa through the Middle East to India. Their preferred habitat is arid steppe, plain or desert, often in the hottest parts of the Northern hemisphere.

Among characteristics of the genus are the following: plump body somewhat dorsoventrally flattened: no gular pouch, but gular fold and tympanum usually visible in both sexes: head covered with small scales, clearly offset from the neck: teeth acrodont and varied, with a central median incisor in the upper jaw in adults: legs short and muscular: short depressed tail with sharp whorls. Preanal and femoral pores usually present in both sexes.

The taxonomy of the genus has been somewhat confused in recent years, with subspecies being promoted and new species or subspecies being described; this confusion is partly due to the less than ideal conditions for research in areas such as Somalia, Sudan and Afghanistan. Walls distinguishes a few basic groups within the genus: the hardwicki group (U. hardwicki) which lack enlarged spiny tubercles on the body but have a higher number of whorls on the tail (34-36) than any other group; the asmussi group (U. asmussi and U. loricatus) which have spinier tails; the ornatus group (U. benti, U. macfaydeni, U. ocellatus and U. ornatus, plus U. philbyi if it is considered a full species) with moderately large scales on the back, whorls of spines not separated from one another under the posterior half of the tail, and no projecting fringes on the outside of the fourth toe; the princeps group (U. princeps and U. thomasi), which have shorter tails (about half the snout-vent length) which are also rather disk-like; the aegyptius group (U. aegyptius) with a large number of small dorsal scales and a scaly fringe on the outside of the fourth toe; and the acanthinura group (U. acanthinura, U. dispar and U. geyri) with tail whorls distinct under the tail right to the tip.

More recently, as of 2022, the three species U. hardwicki, U. asmussi and U. loricata have been assigned to their own genus, Saara.

Uromastyx species are mainly diurnal and terrestrial, although they do have some climbing ability. They are almost wholly vegetarian, with insects being taken only by the young and occasionally by adults as the opportunity and need arises. Furthermore much of their plant food is not only in the form of leafy plants and flowers (as is usual for herbivorous reptiles) but may also take the form of pulses and seeds, the unusual teeth providing the means of shearing and crushing hard matter. Their water needs are very modest, most of their fluid being derived from their food and also possibly from early morning dew on their bodies. On the whole, humidity, and especially humid air, should be regarded as dangerous to these lizards. In the terrarium they require very high temperatures (some Arabian specimens have been recorded as having cloacal temperatures of up to 110 deg F) and a system of burrows. If their rather specific requirements can be met by the conscientious keeper, they turn out to be rather intelligent and friendly pets - Gerald Durrell records an interesting and playful interaction with one in his care in one of his books.

Recently (in the past ten years or so) a number of books and articles have appeared on Uromastyx, which have become fairly popular lizards in the hobby despite the overall lack of interest in the Agamidae as a family. See Bibliography below. As these are rather specialised creatures, if you plan to keep any you should certain avail yourself of a guide to keeping them first. I would certainly not consider them suitable for a beginner to lizard keeping, not least because of their need for high temperatures, largeish enclosures (in the case of the adults) and high amounts of UV lighting.

To date captive breeding has been rather limited, failure rather than success having been the norm. Brumation seems essential for breeding purposes. Terry Thatcher has had some success with these lizards (see Bibliography). All Uromastyx species are now included in CITES Appendix II, and in the European Union are additionally covered by Annex B of Regulation EC 338/97 [Ensenyat].

QUICK INDEX

U. acanthinura, African Spiny-Tail

U. aegyptia, Egyptian Spiny-Tail

U. alfredschmidti, Schmidt's Spiny-Tail

U. asmussi, Iranian Mastigure

U. benti, Bent's Mastigure

U. dispar, Sudanese Spiny-Tail

U. geyri, Saharan Spiny-Tail

U. hardwicki, Hardwick's Spiny-Tailed Lizard

U. leptieni

U. loricata , Iraqi Mastigure

U. macfadyeni , Somali Spiny-Tail

U. occidentalis

U. ocellata , Smooth-Eared Spiny-Tail

U. ornatus , Ornate Spiny-Tail

U. princeps, Armoured Spiny-Tail

U. thomasi , Thomas' Mastigure

 

 

Scientific Name

Common Name

Distribution

Size

Notes

Uromastyx

U. acanthinura [aka acanthinurus]

African Spiny-Tail, Bell's Dab Lizard [F Fouette-queue; D Veränderlicher Dornschwanz]

Morocco, Algeria, Tunisia, Libya, Egypt, Mauritania, Mali, Niger and Chad

16"/40 cm

Exploited by local population for various uses including food. KKS note that this species was extensively researched by Claude Grenot in the 70s, making it "probably the best-known North African reptile": they dedicate several pages to it in their work. There is some debate over subspecies and further confusion is caused by the intergradation of this species with U. geyri in some parts of its range. Activity and annual cycles are dependent upon local conditions: KKS report that a similar correlation with barometer readings has been noted in captives. In optimal conditions the lizards are very active. Although they are by no means creatures of humidity, apparently high levels of heat coupled with drought do place a heavy burden on their metabolism. When feeding, the animals do not consume or damage the plant but select only flower buds, branch tips or leaves. One study revealed that about 5% of the diet was insects, the rest plant matter. Scalation: tail usually has 19 strongly keeled whorls. Coloration: variable and also dependent upon temperature: overall colour may be grey- or yellow-brown, orange, brick-red, yellow or green: patterning is darker to black and may consist of dots, "mesh", small bars, semi-closed circles or a combination of these. Flanks may turn somewhat blue: tail may become spotted with yellow. Head is often dark with coloured spots. KKS note that in the morning on leaving their burrows the lizards are grey, but basking quickly restores their colours. Reproduction: the annual cycle of reproduction is again dependent upon local climatic and geographic conditions. Courtship is somewhat more complicated than in many other lizards, with some female aggression: the sequence can last anything from two hours to a whole day, and pairs may return to it several times before mating. So far a maximum of 23 eggs per clutch have been found. In the wild, incubation takes about 2 months: captive incubation seems dependent upon temperature. High temperatures do not seem to adversely affect the eggs. Sexual maturity in females is reached in about four years. [SOURCE: KKS] 

U. a. acanthinura

Morocco, Algeria, Tunisia, Libya and Mauritania

 

U. a. flavifasciatus

W Sahara (Mauretanian Atar)

May also be considered a subspecies of U. dispar.

U. a. nigerrima

S Algerian Sahara

Tails of this subspecies have longer tails with 22-23 whorls and some enlarged lateral scales. 

U. a. werneri

W Algeria, Morocco

Status of subspecies 

U. aegyptia

Egyptian Spiny-Tail

Libya, Egypt (E. of Nile), Israel, N Saudi Arabia, Oman, Iraq, Iran, Syria, Jordan

24-30"

 

 

Characterised by extremely small dorsal scales and rounded snout. This species is, or was, imported in some numbers, but it is not easy to keep. Scalation: extremely small, slightly keeled dorsal scales in over 300 rows at midbody; anterior denticulated scales on ear opening; spiny fringe along side of 4th toe; up to 20 preanal and femoral pores.  Coloration: dark brown to black: warm specimens may gain a slight hint of colour. Juveniles may be more colourful: see Walls for details. [SOURCE: Walls]

U. a. aegyptia

Libya, Egypt, Israel, Syria

Characterised by spiny tubercles on the sides, in contrast to U. a. microlepis

U. a. microlepis

Saudi Arabia, Oman, Iraq, Jordan and W Iran

This subspecies lacks spiny tubercles on the sides and the dorsal scales are slightly smaller. 

U. alfredschmidti

Schmidt's Spiny-Tail

S Algeria, W Libya

 

Described by Wilms and Böhme in 2000. No other information currently available.

U. benti

Bent's Mastigure/ Poreless Spiny-Tail

S Saudi Arabia, Yemen, Oman

12" 

Occasionally imported from Yemen; can be distinguished from U. princeps (which also lacks pores) by the latter's much shorter tail. Scalation: lacks femoral and preanal pores, although in males the scales are roughened where these would be; anterior ear scales are denticulated; 23-27 whorls on tail. 

U. dispar

Sudanese Spiny-Tail/ Sudan Mastigure

Sudan and Chad

14" 

Poorly known until recently. 

U. d. dispar

Sudan and Chad

 

 

U. d. flavifasciata

W Sahara

 

 

U. d. maliensis

Mali, S Algeria

 

 

U. geyri

Saharan Spiny-Tail, Geyr's Dabb-Lizard [F fouette-queue de Geyr: D Geyrs Dornschwanz]

S Algeria, Mali and Niger

34cm 

Found in mountainous regions of S Sahara, where it lives among rocky outcrops. In winter it shelters in rock crevices several feet above the ground. It intergrades with U. acanthinura, hence there is some question about its species status. Scalation: tail has 21 whorls. Coloration: less colourful than U. acanthinura. Overall light beige to orange: pattern of light brown dots, mainly on the flanks, which may partially form a reticulate pattern: ventral surface light beige. [SOURCE: KKS] 

U. leptieni

 

Oman, UAE

 

Described by Wilms and Böhme in 2000. No other information currently available. [SOURCE: EMBL]

U. macfadyeni

Somali Spiny-Tail

NW Somalia

 

At times treated as a subspecies of U. ocellata.

U. occidentalis

 

W Sahara

 

Possibly formerly known as a subspecies of U. acanthinurus? No further information available. 

U. ocellata

Smooth-Eared Spiny-Tail

NW Somalia, Eritrea, N Sudan, SE Egypt, Djibouti

"

Scalation: anterior ear scales enlarged and smooth, without dentition; femoral pores present. 

U. ornata

Ornate Spiny-Tail

 

 

Egypt, Israel, Saudi Arabia, Yemen

10-12"

Formerly considered a subspecies of U. ocellata: considered by deVosjoli to be one of the most beautiful lizards. Many have been imported into the West and Japan in recent years, but breeding remains sporadic. Walls attributes the popularity of the species to its beautiful coloration and manageable size. However, it should be noted that they are not easy to establish in captivity: deVosjoli strongly recommends the use of no less than 3 full-spectrum bulbs and 1 black-light bulb in the enclosure to avoid the onset of severe health problems. Scalation: tail has only 1 row of enlarged scales under each dorsal row; ventral tail rings at posterior end tend to be fused; 12 femoral pores, plus preanal pores, on each side. Coloration: variable. Overall dorsal brown colour with about 7 transverse bands of bright yellow spots and short bands outlined in bright reddish-brown. The actual patterning of the yellow bands is quite variable between individual specimens. On the sections between the bands are reddish-brown "squiggles", or vermiculations. Several light yellowish and dark bars (of black, green or blue) on the lower sides of the face. Adults are laterally banded with alternate blue-green and yellow bars, continuing the pattern from the back. Males may also develop bright blue-green markings on the face, sides and legs; this phenomenon is less bright in males and juveniles. Tail varies from plain brown to being heavily suffused with yellow and greenish-blue. Throat and belly are covered with irregular brown to blue stripes; in addition, adult males may have a throat heavily striped with blue-black and pale blue. The head of adult males may likewise exhibit various brightly coloured scales. Reproduction: little work has been done, at least successfully, so far with U. ornata, but a brumation period of 2-3 months is held to be mandatory. Males can be distinguished (roughly) from females by having a rather brighter and wider head. [SOURCE: Walls, deVosjoli]

U. o. ornata

E Egypt, Israel, Saudi Arabia

U. o. philbyi

W Saudi Arabia, NW Yemen

12"

Distinguished by a broader tail 

U. princeps

Armoured Spiny-Tail

Ethiopia, Eritrea, E Kenya, Zanzibar

8"

Distinguishable (relatively) from U. thomasi by a somewhat longer tail. Scalation: spines on tail very high and pointed; no preanal or femoral pores. Coloration: dorsally olive-brown with small dark spots; reddish on hind legs and tail. 

U. thomasi

Thomas' Mastigure 

S Saudi Arabia, Oman, poss. Bahrain

6-8"

Scalation: spines on tail fairly low: 15-18 preanal and femoral pores, plus sometimes a second row of preanal pores. Coloration: dorsally either with dark crossbars or tan colour with darker brown "mesh"; if the former, then large dark spots present under tail. [SOURCE: Walls]

Bibliography

Contains useful if brief data on the genus and on the natural history, coloration and husbandry of the species U. acanthinurus and U. hardwicki. It also gives suggestions on the housing and offering the appropriate foods according to the season that would be encountered in the creatures' natural range. Contains useful account by Terry Thatcher of success in breeding U. acanthinurus.

Links

www.kingsnake.com/uromastyx/ - the Uromastyx Home Page.

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