Most lizard species are harmless to humans. Only the very largest lizard species pose threat of death; the Komodo dragon, for example, has been known to stalk, attack, and kill humans. The venom of the Gila monster and beaded lizard is not usually deadly but they can inflict extremely painful bites due to powerful jaws. Numerous species of lizard are kept as pets.






The Blotched Blue tongued Lizard Tiliqua nigrolutea is a skink with a fleshy blue tongue which is used to taste the air and scare off potential predators. They are a robust and relatively large member of the skink family Scincidae that tend to rely on camouflage and bluff as their means of defence. However, if cornered or molested they put on an impressive and effective defensive display.



 If further molested they will bite, but only as a last resort and although their bite is painful due to their powerful jaws, their teeth are blunt and generally don't break the skin. They are of course harmless like all skinks and are inoffensive by nature, often being kept as pets due to their appealing, inquisitive natures and readiness to become tame.



The lizard is about 35 to 50 cm long and is found in wet and dry sclerophyll forests, montane woodland and coastal heathlands. It is an omnivore with a diet consisting of leaves, flowers, fruit, slow moving invertebrates, and small vertebrates. It has heavily lidded eyes that are well protected.



The anus can excrete a foul smelling musk. The tail can also be dropped autotomy when grasped by a predator like most skinks but these large skinks are much less likely to do so.






Geckos are small to average sized lizards belonging to the family Gekkonidae, found in warm climates throughout the world. Geckos are unique among lizards in their vocalizations, making chirping sounds in social interactions with other geckos. An estimated 2,000 different species of geckos exist worldwide, with many likely yet to be discovered.

     

 All geckos, excluding the Eublepharinae family, have no eyelids and instead have a transparent membrane which they lick to clean. Many species will, in defense, expel a foul smelling material and feces onto their aggressors. There are also many species that will drop their tails in defense, a process called autotomy. Many species are well known for their specialized toe pads that enable them to climb smooth and vertical surfaces, and even cross indoor ceilings with ease it is believed that the van der Waals force may contribute to this capability.  
  

These antics are well known to people who live in warm regions of the world, where several species of geckos make their home inside human habitations. These species for example the House Gecko become part of the indoor menagerie and are often welcome guests, as they feed on insects, including mosquitoes. The largest species, Delcourt's gecko, is only known from a single, stuffed specimen found in the basement of a museum in Marseille, France.



 This gecko was 60 cm (24 in) long and it was native to New Zealand. It was probably wiped out along with much of the native fauna of these islands at the end of the 19th century, when new predators were introduced there. The smallest gecko, the Jaragua Sphaero, is a mere 16 mm long and was discovered in 2001 on a small island off the coast of the Dominican Republic.

The Green iguana or common iguana Iguana iguana is a large, arboreal herbivorous species of lizard of the genus Iguana native to Central and South America. The green iguana ranges over a large geographic area, from southern Brazil and Paraguay to as far north as Mexico and the Caribbean Islands; and in the United States as feral populations in South Florida including the Florida Keys, Hawaii, and the Rio Grande Valley of Texas.

A herbivore, it has adapted significantly with regard to locomotion and osmoregulation as a result of its diet. It grows to 1.5 metres -4.9 ft in length from head to tail, although a few specimens have grown more than 2 metres -6.6 ft with bodyweights upward of 20 pounds -9.1 kg.

Commonly found in captivity as a pet due to its calm disposition and bright colors, it can be demanding to care for properly. Space requirements and the need for special lighting and heat can prove challenging to an amateur hobbyist.

The species was first officially described by Swedish botanist Carl Linnaeus in 1758,In the two centuries since then, no less than 17 species and subspecies have been identified with all but one species Iguana delicatissima being found to be invalid. Using nuclear and mitochondrial DNA sequence data to explore the phylogenic history of the green iguana, scientists from Utah Valley State College studied animals collected from 17 different countries.






The Komodo dragon Varanus komodoensis is a species of lizard that inhabits the islands of Komodo, Rinca, Flores, and Gili Motang in Indonesia. A member of the monitor lizard family Varanidae, it is the largest living species of lizard, growing to an average length of 2 to 3 metres -6.6 to 9.8 ft and weighing around 70 kilograms -150 lb.



 Their unusual size is attributed to island gigantism, since there are no other carnivorous animals to fill the niche on the islands where they live; their large size is also explained by the Komodo dragon's low metabolic rate. As a result of their size, these lizards dominate the ecosystems in which they live. Although Komodo dragons eat mostly carrion, they will also hunt and ambush prey including invertebrates, birds, and mammals.



Mating begins between May and August, and the eggs are laid in September. About twenty eggs are deposited in abandoned megapode nests and incubated for seven to eight months, hatching in April, when insects are most plentiful. Young Komodo dragons are vulnerable and therefore dwell in trees, safe from predators and cannibalistic adults. They take around three to five years to mature, and may live as long as fifty years. They are among the rare vertebrates capable of parthenogenesis, in which females may lay viable eggs if males are absent.

Komodo dragons were first recorded by Western scientists in 1910. Their large size and fearsome reputation make them popular zoo exhibits. In the wild their range has contracted due to human activities and they are listed as vulnerable by the IUCN. They are protected under Indonesian law, and a national park, Komodo National Park, was founded to aid protection efforts.






The Oriental Garden Lizard, Eastern Garden Lizard or Changeable Lizard Calotes versicolor is an agamid lizard found widely distributed in Asia. It has also been introduced in many other parts of the world. It is an insectivore and the male gets a bright red throat in the breeding season leading to a common incorrect name of Bloodsucker.



During the breeding season, the male's head and shoulders turns bright orange to crimson and his throat black. Males also turn red headed after a successful battle with rivals. Thus their other gruesome name of "Bloodsucker Lizard". But they don't actually suck anybody's blood! Both males and females have a crest from the head to nearly the tail, hence their other common name "Crested Tree Lizard".



Changeable Lizards eat mainly insects and small vertebrates, including rodents and other lizards. Although they have teeth, these are designed for gripping prey and not tearing it up. So prey is swallowed whole, after it is stunned by shaking it about. Sometimes, young inexperienced Changeable Lizards may choke on prey which are too large. They are commonly found among the undergrowth in open habitats including highly urban areas.

Males become highly territorial during breeding season. They discourage intruding males by brightening their red heads and doing "push-ups". Each tries to attract a female by inflating his throat and drawing attention to his handsomely coloured head. About 10 to 20 eggs are laid, buried in moist soil. The eggs are long, spindle shaped and covered with a leathery skin. They hatch in about 6 to 7 weeks. They are able to breed at about 1 year old.
 

Thorny Devil Moloch horridus is an Australian lizard. It is also known as the Thorny Dragon, Mountain Devil, Thorny Lizard, or the Moloch and is the sole species of genus Moloch.



It grows up to 20 cm -8 inch in length and can live up to 20 years, coloured in camouflaging shades of desert browns and tans; these change from pale colours when warm to darker colours when cold. The species is entirely covered with conical spines that are mostly uncalcified. It also features a spiny "false-head" on the back of the neck, the animal presents this to a potential predator by dipping its real head.



 Females are larger than males. The Thorny Devil's body is ridged in structure, and enables the animal to collect water from any part of its body, which is then channelled to the mouth.

An intimidating array of spikes cover the entire upper side of the body, these thorny scales are a defense against predators. Camouflage and deception may also be used to evade predation. It has an unusual gait, involving freezing and rocking, as it slowly moves in search of its preferred diet.





Chameleons family Chamaeleonidae are a distinctive and highly specialized clade of lizards. They are distinguished by their parrot like zygodactylous feet, their separately mobile and stereoscopic eyes, their very long, highly modified, and rapidly extrudable tongues, their swaying gait, and the possession by many of a prehensile tail, crests or horns on their distinctively shaped heads, and the ability of some to change color.



Uniquely adapted for climbing and visual hunting, the approximately 160 species of chameleon range from Africa, Madagascar, Spain and Portugal, across south Asia, to Sri Lanka, have been introduced to Hawaii, California and Florida, and are found in warm habitats that vary from rain forest to desert conditions.

Chameleons vary greatly in size and body structure, with maximum total length varying from 3.3 cm (1.3 in.) in Brookesia minima one of the world's smallest reptiles to 68.5 cm (27 in.) in the male Furcifer oustaleti. Many have head or facial ornamentation, such as nasal protrusions, or horn-like projections in the case of Chamaeleo jacksonii, or large crests on top of their head, like Chamaeleo calyptratus. Many species are sexually dimorphic, and males are typically much more ornamented than the female chameleons.



Chameleon species have in common their foot structure, eyes, lack of ears, and tongues.
Chameleons are didactyl: on each foot the five toes are fused into a group of two and a group of three, giving the foot a tongs like appearance. These specialized feet allow chameleons to grip tightly to narrow branches. Each toe is equipped with a sharp claw to gain traction on surfaces such as bark when climbing. The claws make it easy to see how many toes are fused into each part of the foot -two toes on the outside of each front foot and three on the inside.






The Oustalet's or Malagasy Giant Chameleon Furcifer oustaleti is a very large species of chameleon that is endemic to Madagascar, but also has been introduced near Nairobi in Kenya though its current status there is unclear. It occurs in a wide range of habitats, even among degraded vegetation within villages, but is relatively rare in primary forest.



With a maximum length of 68.5 cm -27 inch, it is often considered the largest species of chameleon, though some suggest that prize goes to Calumma parsonii.






Brookesia is a genus of chameleons found in Madagascar, that range from small to very small in size, and are known collectively as Leaf Chameleons though this name also commonly is used for species in the genera Rieppeleon and Rhampholeon. It includes the species considered to be the world's smallest chameleons, and are also among the smallest reptiles. They are largely brown and most are essentially terrestrial. A significant percentage of the species in the genus were only identified to science within the last three decades, and a number of species that still have not received a scientific name are known to exist.



 Most inhabit very small ranges in areas that are difficult to access, and due to their small size and secretive nature, they have been relatively poorly studied compared to their larger relatives. Most Brookesia are on CITES Appendix II, the only exception being B. perarmata on Appendix I a species also listed as vulnerable by IUCN. Consequently, a special permit is required to import any of the below species from their native Madagascar, and typically no permit is issued for B. perarmata.

The Cape Dwarf Chameleon Bradypodion pumilum, is a chameleon native to the South African province of the Western Cape where it is restricted to the region around Cape Town. As with most chameleons, its tongue is twice the length of its body and it can be shot out of its mouth using a special muscle in the jaw. This gives the chameleon the ability to catch insects some distance away.

In the past most South African dwarf chameleons were considered to be a subspecies of the Cape species. This is now known to be wrong however; B. pumilum does not appear to have any particularly close living relatives. Like the Knysa Dwarf Chameleon it seems to be a basal offshoot of the ancestral stock which gave rise to all Bradypodion.






Rieppeleon brevicaudatus, commonly known as the bearded leaf chameleon or bearded pygmy chameleon, is a chameleon originating from the eastern Usambara and Uluguru mountains in northeastern Tanzania. It is easily distinguished from others in the Rieppeleon genus by the presence of a "beard" below the mouth, consisting of a few raised scales. At a full grown length of only a few inches (~3" or 8cm), it is marked by somewhat drab coloring in comparison to other chameleons, usually assuming a brown or tan coloring.



It is quite capable of changing its coloration though, often taking on a shade to blend into the background and becoming darker when under stress. It is also capable of compressing its body laterally and producing a stripe down its side, mimicking a dead leaf. It often assumes this form when sleeping in the open. Males are distinguished by a longer tail, more prominent dorsal crest, slimmer body type, and persistent patterning. Like others in the Chamaeleonidae family, it is distinguished by independently rotating eye sockets and a tongue longer than its body.



 

Dasypeltis is a genus of colubrid snakes. It is one of only two taxonomic groups of snakes known to have adapted to feed exclusively on eggs. The other being the snakes of the genus Elachistodon. They are non-venomous and found throughout the continent of Africa, primarily in forested habitats that are also home to numerous species of birds.

The species of this genus exhibit a wide variation in patterning and color, from mixtures of browns and greens, to solid black. Individuals in a specific locality tend to share similar color and pattern. They vary in size greatly, from 30-100 cm in length.

Dasypeltis species tend to have a nervous disposition, and when threatened will perform what is called saw scaling, where it will rub its scales together quickly to make a rasping noise that sounds vaguely like hissing. They are agile climbers, and have a keen sense of smell to tell whether an egg is not rotten or too far developed to be comfortable to eat.



 They have extremely flexible jaws and necks for eating eggs much larger than their head, and have no teeth, but they do have bony protrusions on the inside edge of their spine which are used to aid in breaking the shells of eggs. The process of consuming an egg involves wrapping their mouth around it and drawing it into the throat and then flexing their muscles pushing the egg into the bony protrusions on their spine, which causes the egg to collapse in on itself.






A garter snake is any species of North American snake within the genus Thamnophis. Because of the similarity in the sound of the words, combined with where people often see them, they are sometimes called garden snakes, gardner snakes or gardener snakes, or even garder snakes or guarder snakes. Garter snakes are common across North America, from Canada to Central America, and they are the single most widely distributed genus of reptile in North America.



In fact, the common garter snake, T. sirtalis, is the only species of snake to be found in Alaska, and is one of the northernmost species of snake in the world, possibly second only to the Crossed Viper, Vipera berus. The genus is so far ranging due to its unparticular diet and adaptability to different biomes and landforms, from marshes to hillsides to drainage ditches and even vacant lots, in both dry and wet regions, with varying proximity to water and rivers. However, in the western part of North America, these snakes are more water loving than in the eastern portion.



 Northern populations hibernate in larger groups than southern ones. Despite the decline in their population from collection as pets especially in the more northerly regions in which large groups are collected at hibernation, pollution of aquatic areas, and introduction of bullfrogs and bass as predators, this is still a very commonly found snake.

There is no real consensus on the classificiation of species Thamnophis and disagreement among taxonomists and sources, such as field guides, over whether two types of snakes are separate species or subspecies of the same species is common. They are also closely related to the snakes of the genus Nerodia, and some species have been moved back and forth between genera.





 

Laticauda is a genus of snakes from the family Hydrophiidae. The Laticauda is the least adapted to sea life of all the members of Hydrophiidae; it retains the wide ventral scales typical of terrestrial snakes and has only a poorly developed tail fin. Laticauda are adapted to living on land and in shallow seas.

A sea krait can grow 6.5 feet long - 2 meters. The Laticauda is found through out the south and southeast Asian islands spreading from southern China to northern Australia. It is mostly found in coastal waters.

The Laticauda feed in the ocean, mostly eating moray and conger eels. Some Laticauda eat squid, crabs, and fish. They have never been observed feeding on land.

The Laticauda are often active at night, which is when they prefer to hunt. Even though they contain one of the most toxic venoms in the world their bite is ten times more toxic than that of the King Cobra, Laticauda are usually not aggressive towards humans, and in New Caledonia, where they are called tricot rayé "stripey sweater", children play with them. Bites are extremely rare, but must be treated immediately.

Crotalus scutulatus is a venomous pitviper species found in the deserts of the southwestern United States and central Mexico. It is perhaps best known for its potent neurotoxic venom. Two subspecies are recognized, including the nominate subspecies described here.

This species grows to an average of less than 100 cm in length, with a maximum of 137.3 cm. The color varies from shades of brown to pale green depending on the surroundings.
The green hue found among Mojave rattlesnakes has led to them being known as "Mojave greens" in some areas.

Mojave rattlesnake, Mojave green,  Mojave diamond rattlesnake, Mojave rattlesnake, desert diamond back, Mojave rattler, scutulated rattlesnake. In Mexico, this species is known as Chiauhcóatl Nahuatl, or víbora de cascabel rattle snake in Spanish.  C. s. scutulatus has also been referred to as the northern Mojave rattlesnake.

Campbell and Lamar 2004 support the English name "Mojave rattlesnake" because it is widespread and well known, but do so with some reluctance because so little of the snake's range lies within the Mojave Desert. They also don't support the spelling "Mohave", as opposed to "Mojave", because the name is derived from the Native American term hamakhava.

Morelia spilota is a large snake of the Pythonidae family found in Australia, Indonesia and New Guinea. There are 6 subspecies listed by ITIS, commonly referred to as Carpet and Diamond pythons. An important, if not the largest, predator in many regions, the species traps or constricts its prey until they suffocate.



A large python in the Morelia genus, reaching between 2 to 4 metres in length and weighing up to 15 kg. M. s. mcdowelli is the largest form, regularly attaining lengths of 2.7–3 m (9–10 feet). 
M. s. variegata is the smallest, averaging of 120–180 cm (4-6) feet in length.



The average adult length is roughly 2 m (6.5 ft). However, one 3 year old captive male M. s. mcdowelli, measured in Ireland, was found to exceed 396 cm (13 ft). Males are typically smaller than females, in some regions females are up to four times heavier. The head is triangular with a conspicuous row of thermoreceptive labial pits.



The colouring of Morelia spilota is highly variable, olive to black with white or cream and gold markings. The patterning may be roughly diamond shaped or have intricate markings made up of light and dark bands on a background of gray or a version of brown.

Turtles are reptiles of the order Testudines the crown group of the superorder Chelonia, characterised by a special bony or cartilaginous shell developed from their ribs that acts as a shield. "Turtle" may either refer to the Testudines as a whole, or to particular Testudines which make up a form taxon that is not monophyletic see also sea turtle, terrapin, tortoise, and the discussion below.

The order Testudines includes both extant living and extinct species. The earliest known turtles date from 215 million years ago, making turtles one of the oldest reptile groups and a more ancient group than lizards and snakes. About 300 species are alive today, and some are highly endangered.

Like other reptiles, turtles are ectotherms varying their internal temperature according to the ambient environment, commonly called cold blooded. However, leatherback sea turtle have noticeably higher body temperature than surrounding water because of their high metabolic rate.



Like other amniotes reptiles, dinosaurs, birds, and mammals, they breathe air and do not lay eggs underwater, although many species live in or around water. The largest turtles are aquatic.



The smallest turtle is the Speckled Padloper Tortoise of South Africa. It measures no more than 8 centimetres (3.1 in) in length and weighs about 140 grams (4.9 oz). Two other species of small turtles are the American mud turtles and musk turtles that live in an area that ranges from Canada to South America. The shell length of many species in this group is less than 13 centimetres (5.1 in) in length.

The leatherback turtle Dermochelys coriacea is the largest of all living sea turtles and the fourth largest modern reptile behind three crocodilians. It is the only living species in the genus Dermochelys. It can easily be differentiated from other modern sea turtles by its lack of a bony shell. Instead, its carapace is covered by skin and oily flesh. Dermochelys coriacea is the only extant member of the family Dermochelyidae.



Leatherback turtles follow the general sea turtle body plan of having a large, dorsoventrally flattened, round body with two pairs of very large flippers and a short tail. Like other sea turtles, the leatherback's flattened forelimbs are adapted for swimming in the open ocean. Claws are absent from both pairs of flippers.



The Leatherback's flippers are the largest in proportion to its body among extant sea turtles. Leatherback's front flippers can grow up to 2.7 meters (9 ft) in large specimens, the largest flippers even in comparison to its body of any sea turtle.

The leatherback has several characteristics that distinguish it from other sea turtles. Its most notable feature is that it lacks the bony carapace of other sea turtles. Instead of scutes, thick, leathery skin with embedded minuscule bony plates covers its carapace. Seven distinct ridges rise from the carapace, crossing from the anterior to posterior margin of the turtle's back. The entire turtle's dorsal surface is colored dark grey to black with a scattering of white blotches and spots. Demonstrating countershading, the turtle's underside is lightly colored.






A terrapin is a specific species of turtle Malaclemys terrapin that lives in brackish water.

The diamondback terrapin belongs to the order Testudines along with all other extant turtles. Malaclemys terrapin is the only member of the genus, and is closely related to large genus of North American map turtles, Graptemys. Malaclemys has been divided into seven different subspecies, but these divisions are generally not supported by molecular analyses.



Although sometimes superficially similar to sea turtles in shape, having webbed feet and thinner shells than fully terrestrial tortoises, terrapins do not belong to the sea turtle superfamily Chelonioidea. In British English, the species most commonly referred to as terrapins are members of the family Emydidae including the red-eared slider Trachemys scripta elegans and the painted turtle Chrysemys picta.


Perhaps confusingly, although the genus to which the box turtles belong,Terrapene, sounds similar to the word terrapin, these turtles are not normally called terrapins, but are also in the turtle family Emydidae. Americans only use the term "terrapin" to refer to Malaclemys terrapin, which makes sense considering the meaning of the word.






The Spotted Turtle Clemmys guttata is a small turtle with a shell that can grow between 8 -12 cm (3 to 5 inches.Their upper shell, or carapace, ranges in colour from black to a bluish black with a number of yellow tiny round spots.



Spotted Turtles inhabit a variety of shallow, fresh-water areas such as flooded forests, marshes, wet meadows, bogs and woodland streams in the Eastern U.S. the eastern Great Lakes and east of the Appalachian Mountains and southern Canada Ontario.



Many Spotted turtles are kept as pets, however, this practice is illegal in many jurisdictions, including Canada, due to their threatened status. Adult males have brown eyes, a brown or dark grey beak and chin; adult females have orange eyes, a yellow/orange coloured beak and chin.



Until recently, the genus Clemmys consisted of four species Bog Turtle, Spotted Turtle, Western Pond Turtle, and the Wood Turtle. Recent genetic analysis have revealed that the Spotted Turtle is distinct from the other three species.






The Alligator Snapping Turtle Macrochelys temminckii is one of the largest freshwater turtles in the world. It is a larger and less aggressive relative of the Common Snapping Turtle. The epithet temminckii is in honor of Dutch zoologist Coenraad Jacob Temminck.



The largest freshwater turtle in North America, the alligator snapper keeps to primarily southern U.S. waters, while the smaller, more aggressive common snapper inhabits lakes and streams from South America to Canada.



These turtles can remain submerged for three hours. Typically only nesting females will venture onto open land. Surprisingly, due to the pet trade and other factors the species has found its way to Asia and Europe with a breeding/research center found in Japan.



The Alligator Snapping Turtle is characterized by a large, heavy head, and a long, thick shell with three dorsal ridges of large scales osteoderms giving it a primitive appearance reminiscent of some of the plated dinosaurs. They can be immediately distinguished from the Common Snapping Turtle by the three distinct rows of spikes and raised plates on the carapace, whereas the Common Snapping Turtle has a smoother carapace.

The Spur-thighed Tortoise is one of four European members of the Testudinidae family of tortoises. The other members of the family are Hermann's Tortoise (Testudo hermanni), the Marginated Tortoise (Testudo marginata) and Horsfield's Tortoise (Testudo horsfieldii).



The Greek Tortoise (Testudo graeca ibera) is often confused with Hermann's Tortoise (Testudo hermanni). However, there are nine notable differences that enable them to be distinguished.



The division of Greek Tortoises into subspecies is difficult and confusing. Given the huge range over three continents, the various terrains, climates, and biotopes have produced a huge number of varieties, with new subspecies constantly being discovered.

The smallest, and perhaps the prettiest, of the subspecies is the Tunisian Spur-Thighed Tortoise. It has a particularly bright and striking coloration. However, these are also the most sensitive tortoises of the species, so that they cannot be kept outdoors in temperate climates, as cold and rainy summers quickly cause the animals to become ill. They are also incapable of a long hibernation.






Hermann's Tortoise (Testudo hermanni) is one of five tortoise species traditionally placed in the genus Testudo, which also includes the well-known Marginated Tortoise (T. marginata), Greek Tortoise (T. graeca), and Russian Tortoise (T. horsfieldii), for example.

Testudo hermanni can be found throughout southern Europe. The western population hermanni  is found in eastern Spain, southern France, the Baleares islands, Corsica, Sardinia, Sicily, south and central Italy Tuscany. The eastern population boettgeri Serbia, Kosovo, Macedonia, Romania, Bulgaria, Albania, and Greece. While hercegovinensis populates coasts of Bosnia and Herzegovina, Croatia and Montenegro.



Hermann's tortoises are small to medium sized tortoises that come from southern Europe. Young animals, and some adults, have attractive black and yellow patterned carapaces, although the brightness may fade with age to a less distinct gray, straw or yellow coloration.

The eastern subspecies Testudo hermanni boettgeri is much larger than the western, reaching sizes up to 28 cm (11 inches) in length. A specimen of this size may weigh 3-4 kg (6-9 lb). T. h. hermanni rarely grow larger than 18 cm (7.5 inches). Some adult specimens are as small as 7 cm (3 inches).

Kleinmann's Tortoise Testudo kleinmanni, often called Egyptian Tortoise and occasionally Leith's Tortoise, also includes the Negev Tortoise. It is a critically endangered neck-hiding tortoise. Once more widespread, its numbers are now dwindling. The species is extinct in Egypt, and global extinction is a looming threat unless more actions are taken to protect this species.

Kleinmann's Tortoise is the smallest tortoise in the northern hemisphere . Female tortoises are larger than the males; males are more slender and have a longer tail. Their shells have high domes, and range in colour from ivory to pale gold to dark brown or dull yellow.



 This colouring strongly follows Gloger's Rule as it helps to regulate the impact of sunlight. This allowing the paler tortoise to stay in the desert heat for longer. It is also an effective camouflage in the desert.



The bottom of the shell is light yellow, often with two dark triangles on each abdominal scute. The tortoise's scutes have dark sidings that fade with age. The head and limbs are a very pale ivory yellow to yellowish brown colour.






The Russian Tortoise, Horsfield's Tortoise or Central Asian Tortoise Testudo horsfieldii, but see "Systematics" below is a species of tortoise that is a popular pet. It is named after the American naturalist Thomas Horsfield.



Russian tortoises are a small tortoise species, ranging from about 15 to 25 cm (6-10 inches). They are sexually dimorphic in that the females grow slightly larger, males tend to have a longer tail that is generally tucked to the side, and females tend to have flared scutes on their shells, while males do not.



Coloration varies, but the shell is usually a ruddy brown or black, fading to yellow between the scutes, and the body itself straw-yellow and brown.

This species is traditionally placed in Testudo. Due to distinctly different morphological characteristics, the monotypic genus Agrionemys was proposed for it in 1966. DNA sequence analysis generally concurs, but not too robustly so. Some sources also list three separate subspecies of Russian Tortoise, but they are not widely accepted by taxonomists.