Domestic lizards: what are they? Lizard skeleton. The internal structure of a lizard. Types and names of lizards What does a lizard consist of
The content of the article
LIZARDS(Lacertilia, Sauria), suborder of reptiles. As a rule, small animals with well-developed limbs, the closest relatives of snakes. Together they form a separate evolutionary line of reptiles. The main distinguishing feature of its representatives is the paired copulatory organs of the male (hemipenises), located on both sides of the anus at the base of the tail. These are tubular formations that can turn inside out or retract inward like the fingers of a glove. Everted hemipenis serve for internal fertilization of the female during mating.
Lizards and snakes form a squamous squad - Squamata (from Latin squama - scales, as a sign that the body of these reptiles is covered with small scales). One of the recurring trends in the evolution of its representatives was the reduction or loss of limbs. Snakes, one of the lines of squamates with reduced limbs, form the suborder Serpentes. The suborder of lizards combines several very different evolutionary lines. For simplicity, we can say that "lizards" are all scaly, except for snakes.
Most lizards have two pairs of limbs, visible openings of the external auditory canal, and a movable eyelid; but some of them lack these signs (as in all snakes). Therefore, it is more reliable to focus on the features of the internal structure. For example, all lizards, even legless ones, retain at least the rudiments of the sternum and shoulder girdle (the skeletal support of the forelimbs); both are completely absent in snakes.
Distribution and some species.
Lizards are widely distributed throughout the world. Absent in Antarctica, they are found from the southern tip of other continents to the south of Canada in North America and to the Arctic Circle in that part of Europe where the climate is moderated by warm ocean currents. Lizards are found from below sea level, for example in Death Valley in California, up to 5500 m above sea level in the Himalayas.
Known ca. 3800 of their modern species. The smallest of them is the round-toed gecko ( Sphaerodactylus elegans) from the West Indies, only 33 mm long and weighing about 1 g, and the largest is the Komodo dragon ( Varanus komodoensis) from Indonesia, which can reach 3 m in length with a mass of 135 kg. Despite the widespread belief that many lizards are poisonous, there are only two such species - vest ( Heloderma suspectum) from the southwestern United States and its sister escorpion ( H. horridum) from Mexico.
paleontological history.
The most ancient fossil remains of lizards date back to the late Jurassic (about 160 million years ago). Some of their extinct species were huge. It is assumed that Megalania, which lived in Australia in the Pleistocene (about 1 million years ago), reached a length of approx. 6 m; and the largest of the mosasaurs (a fossil family of long, slender fish-like aquatic lizards related to monitor lizards) is 11.5 m. Mosasaurs inhabited the coastal sea waters of various parts of the planet approx. 85 million years ago. The closest modern relative of lizards and snakes is a rather large tuatara, or tuatara ( Sphenodon punctatus) from New Zealand.
Appearance.
The background coloration of the back and sides of most lizards is green, brown, gray or black, often with a pattern in the form of longitudinal and transverse stripes or spots. Many species are able to change color or its brightness due to the dispersion and aggregation of pigment in special skin cells called melanophores.
The scales are both small and large, they can be located close to each other (like tiles) or overlap (like tiles). Sometimes they are transformed into spikes or ridges. In some lizards, such as skinks, there are bony plates called osteoderms inside the horny scales, which give the integument additional strength. All lizards periodically molt, throwing off the outer layer of the skin.
The limbs of lizards are arranged differently, depending on the lifestyle of the species and the surface of the substrate on which it usually moves. In many climbing forms, such as anoles, geckos and some skinks, the lower surface of the fingers is expanded into a pad covered with bristles - branched hair-like outgrowths of the outer layer of the skin. These bristles catch on the slightest irregularities in the substrate, which allows the animal to move along a vertical surface and even upside down.
Both the upper and lower jaws of lizards are equipped with teeth, and in some they are also located on the palatine bones (roof of the mouth). On the jaws, the teeth are held in two ways: acrodontally, almost completely fused with the bone, usually along its edge and not changing, or pleurodontally - loosely attached to the inner side of the bone and regularly replaced. Agamas, amphisbaenes, and chameleons are the only modern lizards with acrodont teeth.
Sense organs.
The eyes of lizards are developed in different ways, depending on the species - from large and well-seeing in diurnal forms to small, degenerative and covered with scales in some burrowing taxa. Most have a mobile scaly eyelid (only the lower one). Some medium-sized lizards have a transparent "window" on it. In a number of small species, it occupies a larger or entire area of the eyelid, which is attached to the upper edge of the eye, so that it is constantly closed, but sees as if through glass. Such "glasses" are characteristic of most geckos, many skinks and some other lizards, whose eyes as a result are unblinking, like those of snakes. Lizards with a mobile eyelid have a thin nictitating membrane, or third eyelid, under it. This is a transparent film that can move from side to side.
Many lizards have retained the “third eye” peculiar to the ancestors of the parietal, which is not able to perceive the form, but distinguishes between light and darkness. It is believed to be sensitive to ultraviolet radiation and to help regulate sun exposure, as well as other behaviors.
Most lizards have a noticeable opening in the shallow external auditory meatus, which ends with the tympanic membrane. These reptiles perceive sound waves with a frequency of 400 to 1500 Hz. Some groups of lizards have lost the auditory opening: it is either covered by scales or has disappeared as a result of narrowing of the auditory canal and eardrum. In general, these "earless" forms can perceive sounds, but, as a rule, are worse than the "eared" ones.
Jacobson's (vomero-nasal) organ- chemoreceptor structure located in the anterior part of the palate. It consists of a pair of chambers that open into the oral cavity with two small openings. With its help, lizards can determine the chemical composition of substances that have entered their mouths and, more importantly, are in the air and have fallen on their protruding tongue. Its tip is brought to the Jacobson organ, the animal “tastes” the air (for example, to the proximity of prey or danger) and reacts accordingly.
Reproduction.
Initially, lizards are oviparous animals, i.e. lay shelled eggs that develop for several weeks outside the mother's body before the young hatch from them. However, many groups of lizards have developed ovoviviparity. Their eggs are not covered with a shell, they remain in the oviducts of the female until the completion of embryonic development, and already "hatched" cubs are born. Truly viviparous can only be considered widespread South American skinks of the genus Mabuya. Their tiny, yolkless eggs develop in the oviducts, probably fed by the mother through the placenta. The placenta in lizards is a special temporary formation on the wall of the oviduct, in which the capillaries of the mother and the embryo come close enough to each other so that the latter receives oxygen and nutrients from her blood.
The number of eggs or young in a brood varies from one (in large iguanas) to 40–50. In several groups, for example, in most geckos, it is constant and equal to two, while in skinks and a number of American tropical geckos, the cub in the brood is always one.
Age of puberty and life expectancy.
Puberty in lizards generally correlates with body size; in small species it lasts less than a year, in large species it lasts several years. In some small forms, most adults die after laying eggs. Many large lizards live up to 10 years or more, and one brazilian, or brittle spindle ( Anguis fragilis), reached 54 years of age in captivity.
Enemies and ways of protection.
Lizards are attacked by almost all animals that can grab and overpower them. These are snakes, birds of prey, mammals and humans. Methods of defense against predators include morphological adaptations and special behavioral techniques. If you get too close to some lizards, they take a threatening posture. For example, the Australian frilled lizard ( Chlamydosaurus kingii) suddenly opens its mouth and raises a wide bright collar formed by a skin fold on the neck. Obviously, the effect of surprise plays a role, scaring off enemies.
If many lizards are grabbed by the tail, they throw it off, leaving the enemy with a writhing fragment that distracts his attention. This process, known as autotomy, is facilitated by the presence of a thin non-ossifying zone in the middle of all caudal vertebrae except those closest to the trunk. The tail is then regenerated.
Order Squamata Oppel = Scaled
Systematics of the suborder: Lacertilia Owen = Lizards
Family: Agamidae Gray, 1827 = Agamas, agamas (lizards)
Family: Anelytropsidae Boulenger = American worm lizards
Family: Anguidae Gray, 1835 = spindles, spindles
Family: Anniellidae Cope = Legless lizards
Family: Chamaeleonidae Gray, 1825 = Chameleons
Family: Cordylidae Mertens, 1937 = Belttails
Family: Dibamidae Boulenger = Worm-like lizards
Family: Gekkonidae Gray, 1825 = Geckos, [grasping] lizards
Family: Helodermatidae Gray, 1837 = Yadozuby
Family: Iguanidae Gray, 1827 = Iguanas, iguanas
Family: Lacertidae Fitzinger, 1826 = True lizards, Lacertidae
Family: Lanthanotidae Gray, 1825 = Earless monitor lizards
Family: Pygopodidae Gray, 1845 = Scalefoot
Family: Scincidae Gray, 1825 = Skinks, skinks
Family: Teiidae Gray, 1827 = Teiidae, American monitor lizards
Genus: Ameiva Meyer = Ameiva
Species: Ameiva ameiva = Giant, or North American ameiva
Species: Ameiva polops = Island ameiva
Family: Varanidae Gray, 1827 = Monitor lizards
Family: Xantusiidae Baird, 1858 = Night lizards
Family: Xenosauridae Cope, 1827 = Xenosaurs
Brief description of the detachment
Most lizards are quadrupedal reptiles whose elongated body is covered with horny scales, scutes or grains.. Sizes from 3.5 cm to 4 m (weight up to 150 kg). Among modern representatives of the suborder, forms are widely represented both with well-developed five-fingered limbs and without them; there are transitions between these two extremes, and the loss of legs is usually accompanied by a significant lengthening of the body. Species lacking limbs always retain vestiges of the sternum or other bones of the anterior girdle.
Eyes in most species, they are equipped with movable eyelids, but in geckos, naked eyes and some other lizards, they grow together and turn into transparent films before the eyes. In some species, the eyes are completely hidden under the skin, through which they appear in the form of dark spots. There are eardrums. The bladder is usually present. The anterior part of the braincase is not completely ossified. The right and left branches of the lower jaw are connected to each other motionlessly. There is one (upper) temporal arch formed by the squamous, frontal, or postorbital bones. In some lizards, for example, in a number of species of the skink family, this arch is directly adjacent to the parietal bone, as a result of which the superotemporal fenestra may be absent; in others, for example, in all geckos, there is no temporal arch at all, the postorbital arch is usually developed. The pterygoid bones are connected in front to the palatine bones, by which they are thus separated from the vomer. Most lizards have a cranial column, but in some agamas it is greatly reduced. The quadrate bone is usually mobile. The teeth are attached to the outer edge of the jaws (acrodont) or from their inner side (pleurodont). Often there are also teeth on the palatine, pterygoid, and some other bones.
About 3500 species, 20 families and almost 370 genera are known. In the CIS, there are 77 species belonging to 6 families and 18 genera.
Peculiarities scaly cover lizards are of great importance in identifying. The scales of the body in most groups differ significantly in shape, structure, and size. Dorsal scales are smooth, tuberculate, conical, ribbed, etc. Very small scales are called grains, large scales are called scutes. The scutes on the head reach a significant variety in shape, size and location, where each of them has its own name. In some species, the neck is separated from the body by a row of enlarged scales - a collar, in front of which there is a more or less pronounced transverse throat fold. In a number of species of lizards, in addition to large scutes, there are small scales on the head located between the upper ciliary and supraorbital, frontal and supraorbital, as well as in front and behind the supraorbital scutes. In other cases, the head is covered on top with numerous small, irregularly polygonal scutes or scales.
In some lizards, the dorsal scales are almost the same as the ventral ones, but in most the lower surface of the body is covered with enlarged scutes. On the chest, the shields are usually arranged in a triangle or in a different order; the ventrals go in more or less regular rows, parallel or somewhat oblique with respect to each other. In front of the cloacal fissure, many lizards have an anal shield, in front of which there are sometimes relatively large preanals.
Representatives of some families have special formations on the lower surface of the thigh, the so-called femoral pores; each pore pierces one scale, and all together they are grouped in a row located along the thigh. From the femoral pores during the reproduction period, columns of keratinized cells are protruded, the role of which is not entirely clear. If the row is shortened to 1-3 pores, then they are called inguinal. Some geckos have so-called anal pores, which are a continuation of the femoral in the lower abdomen. Geckos also have postcloacal pores, one on each side of the lower surface of the base of the tail; the opening of such a pore leads to a small pouch, in the anterior wall of which, in males, there is a small curved bone.
The caudal scales are arranged in more or less irregular oblique or regular transverse rows (rings). In a number of cases, the number of scales around the ninth to tenth ring is used as a sign that allows one to determine the type of lizard. Rings should be counted on the lower surface of the tail from the first row of large ventral scales located directly behind the small scales of the precloacal fold.
Vision, especially in diurnal forms, well developed; some species are able to distinguish colors; in this regard, the coloring acquires a signal value. Most have developed a parietal eye, usually regarded as a receptor for the light regime and its seasonal changes. Hearing is well developed; the middle ear has a tympanic membrane; in some species it may be covered by skin. Some lizards make sounds. The means of locomotion are varied, from swimming (marine iguanas), climbing trees and gliding (flying dragon) to traversing shifting sands and sheer cliffs and walls (geckos).
According to the degree of development of the femoral and anal pores in many lizards, one can determine gender. The easiest way to determine the sex of geckos, the females of which are devoid of pores at all. Sex determination in most other lizard species requires some practice. So, in males of the family Lacertidae, especially childbirth Lacerta and Eremias, the femoral pores are better developed than in females and have a slightly different shape, occupying almost the entire scale in which each individual pore is incised. Agamas do not have such pores, but there are shallow so-called precloacal pores that occupy almost the entire surface of the scales, located immediately in front of the cloacal fissure; the allocation of these pores give the scales the appearance of a kind of callus. There are other secondary sex signs to determine sex. Thus, the base of the tail in males gradually thins backwards, while in females this transition is much more pronounced. The sex of freshly killed lizards can be easily determined by the presence or absence of characteristic male genitalia, which usually turn outward immediately when pressure is applied to the base of the tail. In fixed animals, to detect them, it is necessary to make a short longitudinal incision, starting from the lower surface of the base of the tail down. In some species, there are sexual differences in coloration.
Many lizards, being captured, throw off their tail. In the future, a new tail of a slightly modified shape grows in place of the fallen one. A restored (regenerated) tail is usually easy to recognize by a slightly different scale, and often by the color of the regenerated part.
most lizards multiply, laying eggs, but some species are ovoviviparous (fusiparous, viviparous lizard). Nutrition diverse: from small invertebrates to large prey (a giant monitor lizard from Komodo Island preys on wild pigs and deer). Food specialization is expressed in marine iguanas (they eat algae) and some lizards that feed mainly on either termites or slugs. Feeding on various harmful insects and molluscs, they benefit agriculture and forestry. There are no poisonous species among the lizards of our fauna.
A large number of lizard species are found in the CIS, of which most live in the south of the country. But some of them, such as, for example, viviparous and agile lizards ( Lacerta vivipara, L. agilis) are distributed far to the north. In the deserts of Central Asia, roundheads are common ( Phrynocephalus), characterized by a rounded head on a movable neck, their body is covered with small horny tubercles. In the houses and among the rocks of the southern regions of the USSR at night you can meet peculiar geckos ( Geckonidae), deftly running along the walls, and even along the ceiling. In the deserts of Central Asia, a large lizard lives - a gray monitor lizard ( Varanus griseus), the length of which reaches 1.5 m. Monitor lizards living on Komodo Island (Indonesia) reach 3 m.
When identifying lizards, the features of the scaly cover of the body are of great importance, in particular the number and location of individual large head shields.
Literature:
1. Key to amphibians and reptiles of the fauna of the USSR. Proc. allowance for students of biol. specialties ped. in-comrade. M., "Enlightenment", 1977. 415 p. from ill.; 16 l. ill.
2. Course of zoology. B. A. Kuznetsov, A. Z. Chernov, L. N. Katonova. Moscow, 1989
3. A.G. Bannikov, I.S. Darevsky, A.K. Rustamov. Amphibians and reptiles of the USSR. Publishing house "Thought", Moscow, 1971
4. Naumov N. P., Kartashev N. N. Vertebrate Zoology. - Part 2. - Reptiles, birds, mammals: A textbook for biologist. specialist. Univ. - M.: Higher. school, 1979. - 272 p., ill.
According to the scientific classification, lizards belong to the reptile class, the scaly order (which also includes snakes) and are divided into twenty families. Lizards to the greatest extent possess the whole sum of the properties characteristic of reptiles. Tenacious fingers with claws on four very mobile paws help the lizard run perfectly, climb bushes and trees, deftly climb several meters up the trunk, easily jump down, and in moments of danger instantly disappear into rodent burrows and under stones.
The body temperature of lizards depends on the ambient temperature, and if it is lower, then life in them is paralyzed. For this reason, reptiles can be seen basking in the sun in the morning hours. And so lizards are active only during the day. Their food consists mainly of small animals. In addition, lizards also eat the fruits of various plants.
Caught by surprise, the lizard easily discards the tail end, which continues to twitch for several more minutes, and thus confuses the enemy, who does not have time to follow the escaped prey. They know how to do it spontaneously, “at will”: muscle spasm literally “cuts off” a piece of the tail in a specially provided place.
Sometimes it is possible to meet a lizard with two tails in the forest. Seeing such a "wonder of nature", you involuntarily recall radiation, bad ecology and terrible mutants. However, neither the one, nor the other, nor the third has anything to do with it. It's just that some predator attacked the lizard, and she tried to escape from persecution, leaving her tail in the teeth of the enemy. But the tail did not come off completely, the lizard lost only a small piece. A couple of weeks later, a new tail grew in place of the lost fragment, and at the same time, almost the whole old one was preserved. So the mysterious lizard runs through the forest with a spare tail.
Lizards use a variety of defense methods. Some, like nimble lizards, acquire camouflage coloration, others, like some felsum geckos, wear bright eye spots on their backs, and others eerily increase. Almost all types of lizards love the last strategy - as soon as the reptile notices the danger, it swells and rises on its feet, visually becoming much larger.
Lizards are found in temperate and warm climatic zones of the Old World. About 150 species live in Europe, Asia and Africa. The family of real lizards got its name not at all due to the fact that there are lizards and fake ones, it’s just that their appearance has become a “classic” of the appearance of a lizard. The most common species in Europe is the quick one.
Lizard quick (Lacerta agilis). The total length is 20-28 cm. Young individuals are brownish-gray or brown above with three longitudinal narrow light stripes edged in black. On the sides in one row are small white marks. With age, the light body stripes blur, and dark brown or black spots appear along the ridge. Males become light green, olive or green, and females are brown, brown and less often green. The belly is usually white or greenish-white in females and greenish in males, usually with rather large dark spots.
Habitat - from Southern England and France to Lake Baikal; in a southerly direction to the line of the Pyrenees, the northern border of the Alps, the northern part of the Balkan Peninsula and the Caucasus region to Central Asia.
Agile lizards inhabit open, well-lit places. Animal burrows are chosen as shelters, but they often dig them themselves. During the mating season (late May-early June), fierce fights often occur between males. The female lays from 6 to 16 eggs, digging them into a shallow hole or leaving them in the depths of the hole. After 7-10 weeks, lizards 5-6 cm long hatch.
Agile lizards do well in captivity. To keep lizards in a home terrarium, you need to catch them in early spring - it is during this period that they best tolerate adaptation in a new place.
The terrarium should have water and an incandescent light bulb under which your wards will warm themselves, resting and digesting food, as well as some kind of shelter (for example, a grotto) - lizards sometimes need privacy.
Very quickly they get used to taking food with tweezers and move from live insects to pieces of chicken and minced meat. Do not place two males in one terrarium - a quarrel will immediately begin, which can lead to serious injuries.
If you take good care of your pets, then it is very possible that they will please you with offspring - a clutch of several miniature eggs, similar in shape to chicken ones.
The average lizard may not have received this name by accident. In everything - from size and lifestyle to internal structure - it is a typical lizard. This reptile inhabits the edges of broad-leaved forests, shrub thickets and light forests, and is found in gardens and vineyards. In the Caucasus, it rises to the mountains to a height of 2500 m above sea level, lives in the east of Asia Minor and the eastern coast of the Mediterranean Sea. The average lizard is an active predator. It preys on insects, spiders, and molluscs, using its forked tongue to contact its prey.
This reptile often digs its own burrows up to a meter long or more. An adult male guards the territory around his shelter and allows only females to enter it. In the spring, after the first molt, the animals keep in pairs, and after mating, the female lays 9-18 fairly large eggs in a specially dug shallow hole in a well-lit place (another clutch is possible in the first half of summer). In total, up to 30 eggs can be laid per season. Usually the female guards and protects the laid eggs. Young lizards hatch from late July to early September. For the winter, these reptiles fall into a stupor in the deep part of their usual shelters.
The viviparous lizard (Lacerta vivipara) is the most common inhabitant of the forests of the middle belt and a representative of the family of real lizards. Total body length with tail 10-15 cm; body length up to 6.5 cm. Females are larger than males. Young lizards are dark brown or almost black in color, often without a pattern. As it grows, the color brightens, a pattern appears, consisting of a dark narrow strip along the ridge, two light ones on the sides of the back and dark ones on the sides of the body; the abdomen of the male is yellow or orange with dark spots, the female is whitish. Distributed throughout Central Europe.
The viviparous lizard adheres to wet places. Squat, short-legged animals move rather slowly, but they can swim and dive well, and in case of danger they often escape in the water, where, after running some distance along the bottom, they burrow into the silt. She is able to easily swim, pressing her paws to her body and acting exclusively with her tail, dive, staying at a depth for a long time.
They feed on worms, centipedes, spiders, insects and insect larvae, seaweed. In general, among lizards, very few use plant food as their main food.
In spring, the viviparous lizard emerges from winter shelters when there is snow in some places in the forest, and the temperature may not exceed +4 °C. Mating occurs shortly after waking up after winter dormancy - in April-May. Does not lay eggs, embryonic development takes place in the body of the mother. After a pregnancy lasting about 3 months, up to 8-12 young lizards are born. At the moment of birth, newborns break through the transparent egg shells and are immediately released from them. Therefore, this lizard was called viviparous.
The northernmost, even beyond the Arctic Circle, viviparous lizard is more than twice as small as the average. An inhabitant of the forest zone of Eurasia, she likes to settle on the edges, clearings, burned areas and raised bogs, and in the southern tundra she prefers the driest bumps. This lizard is not afraid of human proximity and often bends on logs and wooden steps of houses.
Notes of a naturalist
On the edge of the forest, overgrown with a green carpet of grasses, there are tree trunks felled by the wind. In the heat, they heat up so much in the sun that it seems that the scorching heat comes from the wood itself. Many inhabitants of the forest settle on this tree island in the grassy sea. Among them are large song grasshoppers, small dead-eating beetles and even a rodent shrew. This animal regularly visits here to hunt the old-timers of the island - small viviparous lizards.
A sly shrew, dressed in a shiny black fur coat, several times started violent fights with lizards, but they managed to escape and hide in narrow cracks in the wood. Once a shrew was lucky: she grabbed a lizard near the ground itself. Holding the victim by the tail, the shrew tried to drag her to her mink. But the lizard... deftly threw off its tail, which began to wriggle convulsively, and hurriedly disappeared. This fugitive is not sick, she's all right. It's just that all lizards have the ability to autotomy - the loss of the tail. It is perhaps their only defensive trick. Unlike most reptiles, which prefer to live alone, viviparous lizards are sociable creatures and live in large communities.
A graceful six centimeter viviparous lizard, painted in a soft coffee color, deftly climbed a tree and ran up to a sunspot. Describing a small semicircle, she settled herself comfortably on the patch of her choice and turned her back to the sun's rays. In order to heat up almost the entire surface of the body, the lizard parted the ribs, as if flattening out. Another lizard emerged from the grass and froze next to the first, then another and another ...
A large dragonfly, tired of the midday sun, sat down to rest on a small ledge of the trunk. She was noticed by one of the lizards. Quickly scuttling on her tiny legs, she rushed to the dragonfly through the entire trunk of the tree. The dragonfly, recognizing the danger, easily took off, but the lizard managed to jump - by as much as 10 cm! and grab her by the wing. Swaying in the air, the dragonfly tried to fly away, but the brave hunter hanging on the hind wing did not let go. A few moments later, the lizard with a trophy clamped in its jaws - a torn off piece of a transparent wing - fell back onto the tree trunk, and the dragonfly flew away. A minute later, the lucky reptile, licking its lips, continued to bask in the sun.
A sudden quiet rustle in the grass brought the sleepy realm of lizards into disarray. The culprit of the commotion appeared on the trunk - a large, about 15 cm long, nimble lizard. Frozen for a moment, she looked around, and her brown eyes literally dug into one of the frightened livebearers. A quick jerk of muscular legs - and a small lizard is already in powerful jaws. Another moment - and the predator with a rustle disappeared into the grass.
The most beautiful in the family of true lizards is the green lizard (Lacerta viridis). This is a large lizard 39 cm long, 1/3 is the head and torso, 2/3 is a long and brittle tail. The coloration of young lizards and females is grayish-brown or brown, usually with two light stripes on the sides of the ridge. With age, the animals turn green, males acquire a beautiful bright green color with black and yellow dots on top. During the mating season, their throat and neck become blue or bright blue, and the belly is bright yellow. Adult females are distinguished by the presence of two light longitudinal stripes on the upper side of the body, a white belly and throat. The color of the lower part is yellowish to white.
Widely distributed in Western, Central and Southern Europe, but where it is warmer, in the northern part of Asia Minor, in the Crimea, in the Caucasus, in North Africa. Green lizards live on hillsides overgrown with grass and dense shrubs, and in sparse pine forests. They take refuge in deep burrows, sometimes reaching more than a meter in length, usually on slopes, near stones, bushes or trees. They feed on insects, preferring beetles, worms and snails, but sometimes they also catch smaller lizards or young snakes, and occasionally diversify their menu with fruits, such as viburnum berries. During the breeding season between males, it comes to fierce fights with rivals.
A strange lizard lives in the south of Russia - the yellow-bellied lizard (Pseudopus apodus). The most important feature of this lizard is the complete absence of limbs! You will say: this is not a lizard at all, but a snake. No, yellowbell is just... a legless lizard.
Evolution slowly but steadily deprived some lizards of legs. Scientists have discovered lizards with barely noticeable rudiments of limbs - apparently, once the ancestors of the Yellow Tubs had similar ones, but over time they completely disappeared. But why didn’t the lizard legs please nature? The fact is that the most energy-efficient way of movement is crawling. To save energy, some lizards stopped running and decided to crawl.
Yellow-bellied also lives in the south of Europe and in Central Asia. The record length of this lizard is almost 1.5 m, with two-thirds of the length falling on the tail. This lizard retains barely noticeable remnants of the hind limbs, which do not play any role in its life. The inflexible body is covered with large scales. Yellowbelly is often mistaken for a snake, but it has a number of features that are not characteristic of snakes. Like all lizards (with the exception of geckos), the yellowbell has a movable eyelid that covers the eye, and an external ear hole, which snakes do not have. When you take a yellowbell in your hands, you will feel how hard its body is to the touch - it is completely devoid of the flexibility of a snake. The tail of the yellowbell is longer than the body, while in snakes, on the contrary, it is very short.
Yellowbelly is a peaceful and unhurried creature. After basking in the sun, he goes hunting. He needs small snails, slugs, grasshoppers - those who do not need to be chased. The slowness of the yellow-bellied movements loses only when it is very frightened - in this case it can develop great speed, wriggling serpentine along the ground. If you catch this lizard with your hands, then it will not even think of biting you, it will only try to “get out” of your hands.
Yellow-bellies reproduce by eggs, which are laid in the ground on dry slopes and glades. The calm, peaceful nature and large size of the yellowbellies have made them very popular with terrariumists.
Another legless lizard - the spindle - can also be found in central Russia, however, this happens less and less.
| The spindle is not a snake, but a legless lizard |
The spindle is often mistaken for a snake, as it looks similar and moves in a serpentine writhing with its whole body. Like a snake, it has a long body with a head almost fused with the body. She has small legs, and she herself is covered with smooth, shiny scales.
It is painted in modest brown tones, only males in the mating season flaunt blue spots on their backs. The spindle is a medium-sized lizard, a little more than 30 cm, of which two-thirds fall on a long tail, which is easily shed. The spindleworm settles in the forest floor, where it hunts centipedes, slugs and earthworms. In the middle of summer, the female gives birth to 12-15 small formed cubs 7-10 cm long, which quickly begin to live independently.
Most often, the spindle can be observed on the edge of the forest or in a clearing in the evening twilight or in the rain. Of course, in the warm season, when they crawl on the surface of the earth. In October, the spindles hide in deep underground shelters. There they wait out the cold months. In especially convenient burrows, many spindles can gather. Biologists have found up to 100 individuals. Spindles live long enough: in captivity, some have reached the age of 30 years.
The brittle spindle (Anguis fragilis) lives in Europe, Northwest Africa. Body length 38 cm, bright brown color. Does not like extreme heat, often burrows, can hibernate.
Herrosaurs include a couple of dozen species of long lizards with short legs living in Africa and Madagascar. Some African species lack forelimbs. Most of them tolerate captivity well.
Yellow-throated Herrosaurus (Gerrho-saurus flavigularis) lives in South Africa, Madagascar. Body length 46 cm, brown color with a colored throat. Southern alligator lizard (Gerrhonotus multicarinatus) lives in the USA, Mexico. Body length 43 cm. Eats insects, small lizards, etc., drinks from leaves sprinkled with water.
Such an inconspicuous life is led by legless lizards, which evolution never turned into snakes.
Moloch is a small lizard whose body does not grow more than 20-22 cm in length. This animal at first glance may seem unusually scary and terrifying. Moloch has a small head, a thick body and a short tail. From the tip of the tail to the head, the body of this lizard is covered with terrible spines, which are held on shields that cover the entire body of the animal. The largest spines, very similar to horns, are located on the head. Spikes also grow above the eyes. But in fact, this creature is peaceful and completely harmless.
Moloch is common in Australia and is a desert dweller. He lives where there is a large amount of sand. Moloch is able to change the color of his body and remain invisible, adapting to certain conditions of existence.
Moloch eats ants for food, which he lies in wait at the entrance to the anthill, quickly grabs with his tongue and chews with sharp teeth. In just 1 minute, the lizard is able to catch and eat up to 30 pieces of these insects. But in order to get enough, Moloch needs to catch about 1.5 thousand ants.
Living in a hot desert, Moloch can do without water for about 5 months. This is due to the peculiarity of the system of small folds of the lizard skin, into which, like a sponge, water is absorbed - raindrops or dew drops. Due to special muscle movements, this lizard then squeezes the collected water from the folds to the corners of the mouth, providing itself with an additional source of moisture.
In the spring, the female brings offspring. She lays 6-8 eggs, from which cubs are born, covered with small spines.
The gila-tooth or desire (Heloderma suspectum) is the only poisonous lizard. Its venom is deadly even to humans, it can cause severe pain, nausea, vomiting and swelling. The body of the gila-tooth is 60 cm long, weighing up to 2.5 kg and has a brown color with small yellow or bright orange spots. The coloring of the gila-tooth warns the enemy that this creature is dangerous. Therefore, when he sees a predator, the slow goose does not even try to move, knowing that nothing threatens him.
It has a large head with small eyes and a wide forked tongue. On the skin under the scales they have tiny bones, so the entire upper body is covered with small growths. The tail is short, thick and very useful: it is in the tail that the gila-tooth stores reserve fat reserves necessary for survival during hibernation or lack of prey.
These reptiles live mainly in sandy deserts and semi-deserts in the southwest of North America. They dig holes for themselves. Yadozub does not tolerate high air temperature. During the day, the animal rests quietly under the roots of trees or in its hole, and at night it goes out in search of food. It eats insects, worms, frogs, small rodents, eggs and chicks. In extreme heat, he hibernates.
The female gila-tooths lay their eggs in wet sand, in which they mature for a month.
Defensively, the gila-tooth begins to make hissing sounds and blow white foam from its mouth. Poison glands are located on the lower jaw in the oral cavity. This lizard has to bite the prey several times to kill it. The poison is not injected into the skin instantly under strong pressure, but slowly flows down the small tubules on the teeth. Therefore, when biting, they do not let go of their prey for a long time. The deadly poison can affect a person, a horse, a bull or a deer.
Yadozuby fall into hibernation from the end of November to February. During this period, valuable reserves of fat, deposited in advance in the body, come in handy, when these reptiles in one sitting could eat an amount of food equal in volume to 50% of their body mass.
Not too long ago, scientists discovered that gila teeth produce an enzyme that is thought to help people with diabetes.
The frilled lizard (Chlamidosaurus kingii) belongs to the Agamidae family.
They live in the desert plains of northern Australia and southern New Guinea. Body length from 60 to 70 cm, weight 500 g. The color of these lizards is very bright, especially in males. The body is pinkish or dark gray above with dark transverse stripes on the back and tail. Around the neck is a wide, serrated collar, or cloak, interrupted only at the back of the head and deeply dissected in the throat area. The collar reaches 30 cm in diameter. In males, the front collar is brightly colored with numerous pink, black, orange, brown, blue and white spots, while the chest and throat are jet black. Usually frilled lizards wear a "cloak" folded over their shoulders.
The fold, dotted with blood vessels, serves these lizards to dissipate heat, just like a radiator in an apartment.
In the art of creating false sizes, the undisputed champions are Australian frilled lizards. This mobile reptile spends all his free time chasing small animals - insects, scorpions, and other small lizards. As soon as a predator attacks her, she turns around with her whole body, stands up on her hind legs and opens her toothy mouth. Such a pose does not really get on the nerves of the hunter, and when he is clearly about to make a throw, the frilled lizard with a quiet rustle unfolds the “collar” created by the skin fold, which enlarges its head several times. Needless to say, the predator, shocked by such a sudden change in the dimensions of the prey, is retreating. Fleeing, the lizard rises on its hind legs, quickly runs a short distance and dives into the thickets.
Despite their intimidating appearance, frilled lizards are completely defenseless. They spend most of their time in bushes and small trees and move by jumping from one branch to another of amazing length. They feed on small mammals, insects, lizards and snakes. Unlike other lizards, these lizards do not lose their tail.
The female lays from 5 to 14 eggs in the ground, from which young lizards appear after about 2-3 months.
The sail-tailed lizard lives in Java and nearby islands. Its habitat is the dense forests that cover these islands, where a hot, humid climate reigns. She feeds on fruits and insects, which she finds on the upper branches of trees. The total length of the lizard's body can be over a meter, but most of this length is the tail.
Tree lizards move in tree crowns in different ways. For example, a flying dragon living in Southeast Asia is able to move through the air. He succeeds in this thanks to the wide skin folds on the sides of the body, supported by strongly elongated false ribs.
Skinks are a family of lizards that includes over 600 species found throughout the world, but mostly in the tropics. Many lead a secretive lifestyle and prefer to burrow into loose soil or sand. Heat plays a big role. Skinks live longer than most lizards and adapt more easily to new conditions.
Three-toed seps (Chalcides chalcides) lives in southwestern Europe, northwestern Africa. Size 38 cm, color gray, green or brown, burrows into the ground, eats insects, slugs.
The giant lizard (Tiliqua scinoides) lives in Australia. Body length 51 cm. A distinctive feature is dark stripes on the body, a blue tongue. This is a viviparous species. Eats insects, fruits, raw eggs and ground meat.
The short-tailed skink (Trachydosaurus rugosus) is a native of Australia. Body length 46 cm. Color brown or gray.
Five-striped skink (Eumeces fasciatus) inhabits the southeastern United States. Body length 18 cm. Brownish color, young specimens are brighter.
Notes of a naturalist
The Australian semi-desert is overgrown in abundance with undersized shrubs, which the Australians themselves called the bush. In the heat, the bush dries up, turning into an impenetrable weave of branches. In these thickets lives a great variety of living beings.
One of the most amazing lizards, the short-tailed skink, settled in a small mink under a stone. A 30-cm body, ending in a short, as if chopped off tail, is crowned with a massive head with powerful jaws. Why does a slow skink need such powerful jaws? In order to crack the shells of land mollusks even slower than him!
Large scales covering the body and short legs make this lizard look like a fir cone. The movements of the skink are unhurried - it seems that he is not in a hurry to hunt at all. Slowly rearranging its legs, squeezing with difficulty among the thickets, the skink sometimes touches the ground with its tongue, as if tasting it. As soon as a skink finds something edible - a small insect or a rotten fruit - he slowly starts eating.
Here our skink refreshed himself and decided to go in search of a female. Movement on the plain is difficult: small paws allow you to develop only a "turtle" speed. Why did nature deprive the skink of strong limbs, such as, for example, nimble lizards have? Small limbs are one of the adaptations of lizards to life in dense thickets of bushes. Indeed, among the interweaving of branches, roots and stones, it is much better to crawl than to run, and long brittle fingers are only a hindrance here. And the short tail of these lizards has lost its protective function (skinks do not discard the tail) and turned into a storehouse of nutrients - skinks can only eat and drink twice a week. Such endurance is necessary for the inhabitant of the bare desert.
The nature of short-tailed (as skinks are also called) is surprisingly constant: having chosen a girlfriend, the skink remains faithful to her for life and it is in a hurry to meet her, overcoming distances. Sometimes the female or male die. Most often, a widowed spouse does not try to get a new couple and remains alone.
Skinks live not only in Australia, they are found on all continents except Antarctica. One of the most beautiful skinks is the ocellated chalcid. Its graceful long body is painted in golden color and covered with a motley pattern similar to eyes. The scales of chalcids are so thin and fit so tightly to the skin that the lizard looks like an agate craft.
Chalcid settles in the deserts and digs his own shelter. If you frighten him, he will literally dive into the sand, punching a passage with a narrow head and snake-like wriggling body, and emerge in a small distance. Often, chalcides rest, burrowing into warm sand and leaving one head on the surface. As soon as some insect appears in the field of view, the chalcid emerges from the sand and instantly grabs it.
The limbs of the chalcid are very interesting - they are so miniature that for fast movement the lizard completely bends its hind legs to the body, pushes off with its front legs and helps itself with a flexible long body and tail.
Skinks are viviparous, and in the summer the female gives birth to two to five cubs. They grow rapidly, in the second or third year they become adults. As soon as the kids grow up, they begin to live separately, vigilantly guarding their territory. The male not only does not let another male into his “patrimony”, he aggressively attacks. Chalcid fights often end in severe injuries - one of the males loses its tail or even dies from wounds. Skinks live for more than 10 years - for a lizard this is an impressive age.
Monitor lizards are one of the largest lizards in the world: the length of some species can reach more than 2 m.
| indonesian monitor lizards |
They differ from other lizards in two important ways. They have a long, bifurcated tongue, like a snake's. Also, they cannot shed and renew their tail like lizards. Monitor lizards live in Africa, Asia and Australia. The African species is the white-throated steppe monitor. The Nile monitor also lives in Africa. It is slightly larger than the steppe (body length up to 1.5 m).
The monitor lizard settles in rodent burrows, where it hibernates all winter. In the spring, he gets out of hiding. Monitor lizards hunt during the daytime, attacking rodents, lizards, snakes, turtles. They eat eggs and even chicks of birds such as crows and magpies. Quickly climbing the trunks and branches of trees to the nest, monitor lizards grab prey with their teeth and go down. On the ground, they completely swallow the victim. While the stomach is digesting food, the monitor lizard sits motionless with a swollen neck.
Often these animals themselves become the object of hunting. Dangerous enemies for them are wolves, foxes, jackals and large birds of prey. In most cases, monitor lizards flee and hide in their burrows. Sometimes they defend themselves: hiss, show their gaping mouth, beat with their tail.
At the age of 3 years, the female is able to produce offspring. She lays 20-25 eggs in a depression in the ground. At the end of August, cubs hatch from them. Young monitor lizards reach the size of adults at the age of 4 years.
The gray monitor lizard is a huge, two-meter lizard all day long plowing the desert expanses in search of prey. The monitor lizard has a leisurely, slightly shuffling gait, and it looks like a slightly clumsy, restless, tireless boat in a sea of sand and silence. Body size 1.5 m, weight 2-4 kg. The scales of the monitor lizard are colored gray-brown. Throughout the body, from the tip of the tail to the head, there are dark transverse stripes. Now the gray monitor lizard is listed in the Red Book - there are not many of these lizards left in nature.
The two-meter Bengal monitor is brown with yellow spots and darker transverse stripes. Its appearance is remarkable: a powerful body ends with a long tail, on which there is a jagged keel. A graceful, snake-like flexible neck is crowned with a neat pointed head. The jaws of the Bengal monitor lizard are very strong and precise: they can not only bite painfully, but also pick up the smallest insect from the ground. The strong paws of the reptile are “decorated” with long, sharp, curved claws. Young Bengal monitor lizards live in the crowns of trees - there are fewer predators and there is enough prey. But with age, the monitor lizard becomes too massive for this lifestyle and descends to the ground.
Having warmed up in the morning in the sun, he goes in search of provisions - he walks around his territory with long strides. An unusually long forked tongue constantly slips out of its mouth, with which it lightly touches the leaves and the ground - it catches the smells of possible prey. And then luck smiled at our hunter - he met a large scorpion, unsuccessfully trying to hide under a fallen tree.
The lizard deftly grabs it with its jaws, shakes its head, stunning the arthropod, swallows the victim - and almost immediately continues on its way. The venom of a scorpion is unimportant to him. Scorpions and other large spiders are far from the only poisonous dishes on the monitor's menu, and it often eats poisonous snakes.
The reptile protects its site from encroachment: if it meets another monitor lizard, then skirmishes cannot be avoided. Opponents scratch and tear each other with the claws of powerful hind legs, like cats, and inflict terrible bites.
Only during the mating season monitor lizards become less aggressive.
Females leave clutches of eggs, from which a new generation will appear in a few months. The kids are in a hurry to move to the trees in order to safely start an independent life. Insects will be the first food, and only later, when the predator gains strength, will it begin to hunt larger prey. By the way, the Bengal monitor lizard is a universal predator: it hunts not only on trees and on the ground, but even under water! In water, this lizard is unusually maneuverable - with its wide tail, the monitor lizard changes the direction of movement and is able to easily catch even a very agile frog.
The Bengal monitor lizard has no less interesting relatives. The African Cape monitor lizard, an inhabitant of dry semi-deserts, differs from its slender Bengal counterpart: it is stocky, short-legged, with a short, powerful tail. But the most surprising thing about the appearance of the Cape monitor lizard is the neck. Immediately behind the flat, impressive head, a "collar" of wide scales begins.
Why the monitor lizard needs this structure, you can understand by seeing it on the hunt. The Cape monitor lizard does not chase game - it sits in a secluded corner and waits. As soon as a rodent appears in the throw zone, a predator makes a lightning attack. And having grabbed a rodent, it closes its eyes, which literally sink into the sockets - this is how the reptile protects its organs of vision from possible injury. And no matter how it bites, no matter how the unfortunate rodent fights back, it will not be able to harm the armored lizard: the large scales covering the head and neck of the monitor lizard do not allow biting through the skin until it bleeds. In the meantime, the rodent is trying to bite the monster, the monitor lizard crushes the victim, breaks her neck, depriving her of mobility, and swallows.
Monitor lizards, the most developed lizards in all respects, have a special attitude to hunting. For them, this is not only a way to get food, but also entertainment. Sometimes the monitor lizards kept in captivity behave strangely: the lizard is not in a hurry to kill the frog thrown to it to be eaten, but pushes it with its muzzle, forcing it to run away, then catches up and drives it forward again. Such a game of "cat and mouse" can continue for quite a long time, but hunger still prevails over the desire to have fun - and the monitor lizard attacks its prey.
The intelligence of monitor lizards and their excellent control over their bodies are striking. For example, when hunting, when a monitor lizard realizes that he cannot grab a frog with his jaws, he instantly attacks it in a different way - “nails” it to the ground with sharp claws.
The largest monitor lizard is the Komodo dragon. This monitor lizard reaches a size of over 4 m (if you count with a tail), and its weight exceeds 150 kg. It lives on small islands in Indonesia - Komodo, Rinja, Padar, Flores and was discovered only in 1912. He settles in sparse groves. Young lizards live in trees, and when they mature, they move to the ground.
This giant voracious lizard eats everything living that catches its eye, but it can also feed on carrion. Large adult animals are able to hunt wild boars and deer, they can grab and swallow their own offspring. Komodo dragons are so big that together they can even hunt deer! There are even cases of monitor lizards attacking people.
Not all lizards want to live on the ground, some have chosen to settle on the vertical surface of walls and tree bark. This is the best way to hide from the pursuit of predators - who dares to go mountain climbing! But for many geckos, acrobatic stunts are even quite successful; moreover, there are geckos that never descend to the ground. There are so many geckos that it is simply impossible to meet all of them. The gecko family includes over 900 species.
The gecko is a small lizard. It has a large head, on which are located two large eyes with narrow pupils. There are no eyelids on the eyes, but they are protected by scales, which the gecko rubs all the time with its elongated tongue. The short, flattened body rests on well-developed legs. The body of the smallest gecko is only 7.5 cm long, larger species reach 35-40 cm. All geckos move perfectly on horizontal and vertical surfaces, which from the side seem absolutely smooth. In this they are helped by sharp claws on their fingers and a special shape of scales that allow geckos to cling even on ceilings. Some geckos, thanks to their amazing fingers, can even hold on to glass!
In speed and dexterity of movements, they are not inferior to many of their daytime relatives, enlivening their activity with various sounds inaccessible to daytime lizards. Most of them are capable of making rather loud squeaks, chirps, clicks or croaks. The native names of these animals, such as "chichak" and "tokey", are onomatopoeic names. The very word "gecko" comes from the cry of one of the common African species.
Geckos live in hot countries. Often they settle under the roofs of buildings, living next to a person. Since they are nocturnal animals, after dark they begin to hunt for insects. These reptiles are very mobile, so their tails often break off. But they grow back and reach the desired length in a month. You can often find a large number of geckos in one place. However, these animals most likely lead a solitary lifestyle.
Most geckos are oviparous. The female usually lays 1-3 eggs in a shallow hole or under a rock, but many times a year. Laid eggs are soft to the touch. They then harden due to contact with air. The young hatch out almost immediately.
Geckos are not at all dangerous to humans. But among themselves, these animals are constantly in conflict and arrange fights, using sharp teeth. Many geckos are capable of making sounds similar to the croaking of a frog or the quiet barking of a dog.
Geckos are nocturnal and are mostly browns and grays that blend into tree trunks, sand, or soil. The appearance of the gecko is conducive to communication. But appearances are often deceiving. This little guy bites pretty hard. Deep wounds remain at the site of the bites.
One of the smallest lizards in the world, perhaps, is the flat-tailed gecko living on the island of Madagascar. Its size is 120 mm and its weight is 10 g. This night lizard, like all other geckos, lives on trees in the rainforest. The protective coloration and the peculiar shape of the body and tail easily make it possible to take it for a knot or an outgrowth on a trunk with a dried leaf (the tail acts as a leaf).
On the surface of residential buildings in the Mediterranean, a wall gecko very often settles. This little lizard is painted in discreet gray and brown tones. In general, all geckos differ in appearance from other lizards: their stocky body is covered with small scales with separate prominent scales merging into a certain ornament. The wall gecko has very large, just huge eyes, which gives it away as a nocturnal predator.
An inhabitant of Southeast Asia, the toki gecko is much larger than the wall gecko - its length reaches 35 cm. And it is colored much brighter: red and blue dots are scattered over the blue skin. Toki is an incredible owner: not only males, but even females protect their possessions! As soon as a stranger gecko appears, the owner meets him. He freezes in front of an uninvited guest, opens his mouth - and the mucous surface of his mouth is eerily black - and begins to nod his head. As soon as the enemy takes a step, the owner of the territory immediately rewards him with a bite. And the toka's bite is real - the jaws can even bite through human skin.
Like all geckos, toki can crawl along sheer, smooth (in our opinion) walls. The attachment plates on its flat, widened fingers are covered with rows of bristles, which bear microscopic cups that cover the smallest protrusions of the surface. The “sticking” is so strong that a gecko crawling along the wall can hardly tear its paws off it.
Some live among rocks or on sand. On the hot sand of the desert, the gecko "dances" to cool its paws. He lifts them one by one, and sometimes even rests his stomach on the sand, raising all his paws at the same time.
Some geckos are ardent sun worshippers. Such is the Madagascar day gecko, or felzuma. It lives only in Madagascar. Perhaps this gecko can be called one of the most beautiful lizards: red spots are scattered over the light green, like a velvet background of its skin. This coloring well masks the animal among plants in the light of sunlight.
Ptikhozoon - gecko is small and inconspicuous. But he has one amazing feature - a membrane that connects his fingers and goes into a fold on his side. When the lizard jumps from tree to tree, the membrane opens - and the bird-zoon overcomes several meters in gliding flight. So lizards, to the best of their modest strength, were able to conquer the air environment.
There are also ground geckos. The most famous of them is the spotted eublefar, an inhabitant of Iran and neighboring countries. Eublefar is not a small lizard, some individuals reach a length of 20 cm. This gecko is distinguished not only by its size, but also by its contrasting color: dark brown spots are scattered over the coffee background. By the way, the name "eublefar" literally translates as "having beautiful eyelids." Indeed, the eyelids of the eublefar are covered with small bright scales, favorably shading the brown eyes.
Eublefars are very slow - it seems that the lizard takes every step after a short thought. Eublefar is so accommodating that, even if he is picked up, he will not bite. For a quiet disposition and rare unpretentiousness, this lizard was loved by terrariumists. You can settle a eublefar in the simplest terrarium, where, eating crickets and cockroaches, he will live for more than one year, delighting the owner with his behavior.
The squeaky gecko (Alsophylax pipiens) lives in the lower reaches of the Volga - a rather pretty creature: with a grayish or yellowish body, usually with five dark brown transverse stripes on the back and stripes of the same color on the tail and outer side of the legs. The total length of even the largest individuals does not exceed 8-9 cm. These geckos live on the slopes of cliffs, they are active mainly at night, but in cloudy and warm weather they are often found during the day. Their food is made up of various insects, which are mined both on the ground and on the branches of small shrubs.
No matter how amazing geckos are, they cannot compete with the recognized queen of the world of reptiles - an ordinary iguana. Iguanas are close relatives of agamas, chameleons and other small and large lizards. The smallest iguanas do not grow up to 10 cm.
A terrestrial iguana with a body length of 1 m occupies a middle position.
The largest of the iguanas is the common or green iguana (Iguana iguana), which lives in northern South America. There are specimens up to 1.8 m long. This lizard received its second name for the bright green color of the body, like a leaf, across which there are dark stripes, limited, as a rule, by narrow light borders.
Different species are adapted to different habitat conditions. Some live in deserts and steppes, others live in tropical rainforest, on the coast or high in the mountains. Depending on this, the color of iguanas also varies. Woody species are usually painted in green tones, desert and rock-dwelling - in sandy, brownish and beige - to match the surface on which they live.
Most iguanas are predators, feeding on insects, spiders, centipedes, worms, etc. The largest ones also eat vertebrates, mainly lizards. Perhaps only the already mentioned green iguana belongs to the number of vegetarians. They hunt on the ground, and some even high on the branches of trees.
Most iguanas live in Central and South America. But some live in Madagascar off the southeast coast of Africa and on various Pacific islands. Some iguanas probably sailed to these islands on some floating objects carried by sea currents, others could have been introduced by traders and travelers. The land iguana comes from the South American mainland, 1000 km away from the Galapagos Islands.
The marine iguana (Amblyrhynchus cristatus), or rather the marine lizard, is the only one that has chosen the sea as its habitat.
An elongated body, a low crest along the entire back, for which it is called a dragon, a long oar-shaped tail. The coloration is dark gray to black, in places with yellowish or reddish spots. Length up to 1.75 m, of which the body is about 50 cm. It eats algae thrown onto the stones by the surf, or gets them from the seabed.
It lives only on the Galapagos Islands off the coast of South America, where it inhabits a narrow coastal strip covered with rocks, without penetrating into the depths of the island. There, these lizards can be seen all over the coast. They bask in the sun, occasionally sailing out to sea. Striking with a flat tail, the lizard quickly moves forward. Diving, the iguana is kept at the bottom with its claws, long, three-pointed teeth biting the algae.
The marine lizard can stay under water for up to 10 minutes and descend to a depth of 12 m. Excellent swimming, iguanas, in case of danger, nevertheless prefer to hide on land, where they have practically no enemies, while in the sea they are often attacked by sharks. Each male marine iguana has his own stretch of coast, which he guards from other males; to drive away the stranger, the male iguana butts his head. The female lays 2-4 eggs in sandy soil, the cubs appear after 3-4 months.
Basilisk tree lizards, close relatives of iguanas, are distinguished by their amazing appearance: their head and back are crowned with a high unusual crest. This lizard loves to rest on the branches of trees hanging over the water. In case of danger, it jumps down and ... runs through the water on its hind legs, escaping from persecution. How is she not drowning? Do not be surprised: there is a completely rational explanation for this phenomenon: the basilisk moves so quickly with its legs that it easily keeps the body on the surface.
Basilisk lives in the dense forests of South America. It feeds on fruits and insects; the body length of an adult basilisk can reach 75 cm.
In ancient Russia, a monster was called a basilisk - a cross between a rooster, a toad and a snake, endowed with terrible magical powers. It was believed that if you looked into his eyes, you would turn into stone.
Chameleons (Chamaeleontidae) are reptiles, relatives of lizards.
The ability to quickly change the color and pattern of the body, characteristic of chameleons, has become widely known, from where the name "chameleon" itself came from - after the name of a mythical creature that can change its appearance. The usual color of animals is greenish or brown.
Chameleons are the most unsurpassed masters of camouflage. They have brought the art of disguise to such a degree of perfection that there is nowhere else to go: even the saying appeared - "changeable, like a chameleon." The color change occurs under the influence of both external stimuli - temperature, light and humidity, and as a result of hunger, fright, thirst, irritation, etc. As a rule, the color harmonizes well with the surrounding background, hiding the animal from the eyes of numerous enemies. The mechanism of color change in chameleons is not fundamentally different from the same mechanism in common tree frogs. Only in chameleons this mechanism is richer in different colors and also acts much faster.
Chameleons are slow-moving lizards with tall, narrow bodies. Another sign of a chameleon is the claws on the front and hind legs, which are convenient for grasping branches (the fingers are located in two groups opposed to each other). Chameleons can also be considered unsurpassed "top climbers". The toes on the paws of the chameleon cover the branches like pincers, in addition, the tenacious tail helps it to stay absolutely still.
The eyes are round, protruding and can move independently. When hunting, the chameleon freezes on a branch, while constantly rotating its eyes in different directions, so that it is almost impossible for an insect to notice it. At this time, the lizard's tongue, equal to half the length of the body, is in the mouth in a compressed form, like a spring.
When prey appears, the chameleon's eyes aim in one direction, the tongue shoots at the victim, hitting it with an expanded sticky end, and then it returns to the mouth with the stuck insect. The entire "capture" takes a twentieth of a second from the lizard. In some species, the length of the tongue is equal to the length of the body of its owner.
There are about 85 species of chameleons. They are found in Madagascar and throughout Africa except the Sahara, as well as in India, Pakistan and Sri Lanka. In Southern Europe (in the south of Spain), one species also lives. They were met in the mountains at an altitude of up to 4000 m. The largest species - a giant chameleon - lives in Madagascar (its body length is 63 cm; tail length is 35 cm).
Lobe-nosed chameleon (Chamaeleo dilepis) lives in Africa, body length 33 cm. More beautiful and hardier than Mediterranean species; varied diet with flies.
Jackson's chameleon (Chamaeleo jacksoni) lives in East Africa, body length is 30 cm. The main color is greenish; males raise their horns to fight.
The two-banded chameleon (Chamaeleo bitaeniatus) lives in the Kenyan highlands, body size is 13-16 cm. The color is brownish, viviparous.
The common chameleon (Chamaeleo chamaeleon) is an inhabitant of southwestern Europe, the Mediterranean, and northern Africa. Body length 25 cm.
Most chameleons are native to Africa and southern Asia. They need a vivarium with a temperature of 24-29 °C; plant leaves should be sprinkled with water for drinking. Usually chameleons do not live long.
Chukwalla is an agama lizard living in deserts and semi-deserts in the west of North America, Mexico, mainly among rocks.
Chukwallas are close relatives of iguanas and sea lizards. To see it, you need to find a suitable place around noon. And somewhere you will be able to see a chukwalla basking in the sun. When you try to approach her, the chukwalla disappears with lightning speed in a crevice of rocks. Sensing danger, she takes in air many times, literally pumps herself up, and thus gets stuck in her shelter, so that it is impossible to get her out of there.
Arizona Chukwalla. Body length 14-20 cm This is a large, flat-bodied lizard; legs are thick, fingers are long and thin; a tail with a wide base and a blunt tip; males have a darker head, chest and shoulders, gray and brown spots; the rest of the body is rufous or light gray; in females and young animals, transverse stripes on the body and tail; in general, the color changes depending on the intensity of the sun's rays - it darkens or brightens. It feeds on various desert grasses and insects.
The female lays 5-16 eggs from June to August.
Bloodsucker calot. This agama is the most common tree lizard in the rainforests of Asia. All calots, like chameleons, quickly change their color under the influence of temperature, lighting, and also their own mood. This one, for example, being frightened, becomes black-brown. And in the mating season, the lips and throat of the male turn bright red, hence the strange name of the species. However, this lizard bites to the point of blood.
Roundheads belong to the Agama family, of which there are about 200 species, and they live in Asia, Africa, Australia and in some regions of Europe.
An eared roundhead can take on a very intimidating appearance when danger arises. She opens her mouth wide and straightens the leathery folds on its sides. These folds are bordered by a series of spikes that look like teeth. In combination with the red color, this gives the roundhead a more ferocious and large appearance and deters most attackers. The pursuer does not want to experience the bite of such jaws, and he retreats.
Small roundheads bask in the morning sun. Having chosen a flat stone, the lizards freeze on it as living statues, absorb the life-giving heat and warm themselves from the coolness of the night. As soon as the sun rises higher, the roundheads leave their homes to dine on the ants. Deftly picking up insects, lizards quickly eat up and again go to rest. But they will no longer be able to lie down on the warm sand - it has warmed up to an incredible temperature: you can bake an egg in it! And, in order not to get burned, the roundheads perform a funny dance: they jump, raise two opposite legs in turn. Such a dance will last until the evening, until the night cools the hot sand.
Another inhabitant of the waterless desert adapted to the hot sun in a different way. The thorntail lizard did the easiest thing - she took it and got used to high temperatures. When the spiketail emerges from its hiding place in the morning, it is a deep brown, but once it warms up, it turns pale, as if fading. What are the repaints? Morning dark coloring helps the body of the lizard absorb as much heat as possible, because it is the dark color that attracts the sun's rays. And then the spiketail discolors to protect itself from overheating.
By the way, the spiketail also changes color when the mood changes: it gets scared - it tries to discolor in order to become invisible and hide, and if it argues with a competitor for territory, it fills with black colors of anger and indignation.
Thorntail is a peaceful vegetarian, but he needs to defend himself from predators, so he has a terrible weapon - his tail. It is thickened and covered with pointed spikes - a real mace. A predator that tries to attack this lizard will immediately receive a strong blow with its tail.
Thorntail can go without water for many days, content with moisture, which it extracts from the soft parts of desert plants.
In the dry thickets of South America, another inhabitant of semi-deserts, the tegu, settles. The length of this lizard rarely exceeds 1 m, but it is an unsurpassed predator. Tegu in its appearance combines the elegance and swiftness of the forms of a real lizard and the power of a monitor lizard. It is painted in alternating blurred golden and black stripes, which ideally mask the animal in the bushes - they resemble the play of light and shadow on the ground.
These lizards are extremely intelligent. On cool evenings, they leave their territories and go in search of food to human habitation. Making their way into chicken coops, they eat eggs and chicks. People do not remain in debt and hunt tegu not only in revenge for the robbery, but also because of the delicious meat.
extinct lizards
No one knows why megalania died out. We can only assume that it could be exterminated by people who found it frightening because of its huge size. Perhaps, like the heroes of the folk epic who went to kill the dragon, those who managed to kill the megalania were glorified for delivering people from the supposedly terrible monster.
Be that as it may, today the largest monitor lizard lives in Australia, and its body length is less than 2 m; its scientific name is Varanus giganteus. Also in Australia, the remains of a giant monitor lizard were discovered, showing that, in all likelihood, it died out less than 90,000 years ago.
Not so long ago, for a variety of reasons, other lizards also became extinct. For example, some inhabitants of the West Indies became the prey of mongooses, cats, rats and birds.
In 1926, the first living specimens of a giant lizard known as the Komodo dragon, as well as the Komodo dragon or ora, never seen outside of Asia, were brought to the New York Zoo. They looked impressive, but how could they compete with megalania.
Considered an extinct relative of the Komodo dragon, the megalania, or giant monitor lizard, that lived on the territory of modern Australia, was huge. It could reach 6 m in length.
A carbon analysis of the fossil megalania was carried out, which showed that this animal lived at the same time as some of our ancient ancestors. No wonder so many legends sprang up around him! Today's Komodo dragons are only half that size.
The reasons for the extinction of lizards include extermination by other animals, the ineffectiveness of attempts to breed in captivity, excessive destruction by people for sport, destruction of the natural habitat, droughts and other natural disasters, unreasonable fear of people, which led to extermination.
However, some of the extinct lizards were hunted by people simply for sporting interest; and one species that lived on a tiny island off Guadeloupe disappeared after its habitat was destroyed by a terrible hurricane.
In addition, construction sometimes affects the population of reptiles. For example, on Menorca, a small island in the Mediterranean Sea, it was for this reason that the lizard from the island of Rattay disappeared in 1950.
Droughts that destroyed vegetation no doubt contributed to the disappearance of the giant skink from the Cape Verde Islands. The convicts exiled to a small area of these islands in 1833, during a terrible famine, were simply forced to make the surviving lizards part of their main diet. It is clear that the number of this species must have rapidly declined even more.
Persistent attempts by scientists to breed some rare species of lizards in captivity did not always bring the desired result.
Keeping lizards
Lizards are very cute pets. They are clean, they do not smell. Cages should be spacious, with constant heating for tropical species. Hardy lizards need warmth only during the day, but for sleeping or wintering they need frost-free night or winter rooms. Sunlight and natural, vitamin-fortified foods help keep the lizards in good condition. Some of them are never tamed and try to quickly slip out of the hands or into any crack in the cage. Lizards usually do not live long - many of them are less than five years old.
Feeding. Tiny lizards eat fruit flies or insects collected with a net in the grass. Most small to medium sized lizards feed on live spiders and insects such as flies, mealworms, crickets, locusts, and cockroaches. Some lizards love earthworms. Spindles catch slugs. Large lizards and some skinks may take canned dog food or ground raw meat with a beaten raw egg in addition to fruit. Iguanas require some animal protein, but mostly eat fruits or greens. Grinded cuttlefish skeletal plates and multivitamins should be added. If animal fights start and there is a danger that some of them may starve, feed the lizards individually.
Appeal. Grasp the lizard tightly, holding two limbs between your fingers if possible. Make sure she doesn't slip away, and never grab her by the tail - it can break off.
Most lizards are designed to run on the ground, but some have bodies designed for more specialized lifestyles. Typical land dwellers have a long, low body, short legs and a long tail. Geckos have small hairy pads on their fingers that allow them to cling to even surfaces. Therefore, geckos, hunting for nocturnal insects, can run along walls or ceilings. Asian flying lizards fly from tree to tree using skin folds on the sides of the body. Some burrowing lizards have a shiny, legless body that helps them burrow into sand or soil.
Hardy lizards can be kept part of the year or the whole year in special reptiles. Be aware of the potential for fights and cannibalism when keeping some reptiles together.
The street reptile consists of:
1 Fenced plot in an open, sunny position.
2 Asbestos or PVC wall attached to support posts: 90 cm above ground and 30 cm below ground. You can make an alternative reptilian wall. A PVC wall is easy to make and cheap, but the material becomes brittle and can break in windy conditions. For greater strength, build a wall of brick or stone with a gable top of shingles to prevent reptiles from escaping or rodents from gaining access.
3 Layers of plastic overlapping each other
4 Large rocks and creepers, shrubs or other plants. (Must be at a distance from the wall of the reptilian).
5 Bushes for cover and shade.
6 Sandy stony mounds (with stones or broken bricks inside) at least 45 cm high or more,
where temperatures are around zero degrees in winter. (Arrange at a distance from the walls).
7 Area with low level for drainage.
8 "Beach".
9 A pond lined with a film or with a cement bottom and walls - for wintering aquatic turtles with a depth of at least 60 cm.
10 Shallow, gently sloping edge of the pond.
11 Fixed log and water plants.
12 Dry branches and logs where you can bask in the sun.
Lizards also need dry, ventilated glass terrariums or wooden or metal cages with a glass front. All climbing species require tall terrariums to accommodate branches or rocks. Cages with poisonous lizards must be locked. For heating, you can use a light bulb or a tubular heater, you only need to protect the animals from contact with the heat source. Reptiles that bask in the sun especially need to have both warm and cooler spots in the terrarium. When keeping snakes, make sure the ground is level. Desert dwellers need fine sand, rocks and cacti. Greenhouse plants and loam or peat on a layer of coal lying on gravel are suitable for iguanas, but excess moisture must be avoided. Paper bedding is the easiest to clean.
Terrarium suitable for lizards:
1 Glass aquarium.
2 Perforated zinc cover.
3 Electric bulb for heating.
4 Reflector.
5 Thermometer.
6 Branch.
7 Cork tree bark.
8 Bottom covered with gravel.
9 Cactus.
10 bowl of water.
11 Shady hiding place.
12 Stones at the bottom of the aquarium.
temperature gradient. The terrarium should have areas with different temperatures, allowing the animal to choose a place where it will feel most comfortable. A rock or branch close to the heater provides both a hot spot and a cooler spot.
Wintering. In nature, hardy reptiles stop feeding in the fall, dig into the ground or sink to the bottom of the reservoir and fall into a stupor. In captivity, if kept warm, they remain active but may lose their appetite. Most reptiles live longer if they are allowed to winter somewhere in cold but not freezing conditions. Wake them up in early spring. In mild weather, wintering reptiles become active and able to tolerate starvation until they are fully warmed up and start eating.
Lizards wintering outside. Hardy species burrow into heaps of rocks. You can make a mound of stones and earth with a cavity inside, lined with fallen leaves and equipped with a thin inclined drainage tube to drain water. In this case, the wintering place itself turns out to be in a dry and non-freezing area.
Lizards wintering in the house. Fill the boxes with fallen leaves and dry moss and place them somewhere cool but protected from drafts and frost.
Reproduction of lizards.
Some lizards are viviparous, while others lay their eggs in soft soil. Hatching requires warm and moist conditions. (Too much humidity causes fungal infections to develop; too little humidity can dry out the eggs.) The young hatch in 10 to 12 weeks or less; they must be separated from their parents if they are large enough to be able to harm them. Some cubs need special food and a higher temperature than adults. For most of them, the sun is important.
Hatching in a package. Reptile babies can hatch from eggs in a plastic bag, at the bottom of which lies a layer of wet sand, earth or sphagnum. Place the eggs, without turning them, in individual holes in the sand or other material. Tighten the top of the bag with a rubber band. Place the bag in a ventilated cabinet, on a radiator, or let it float in a tropical aquarium - anywhere with a temperature above 27°C. If there are no small droplets of moisture on the walls of the bag, add a few drops of water to it. After a few weeks, start checking your eggs daily to see the first signs of hatching.
Hatching in a box. Reptile eggs can also be allowed to develop in a large wooden box heated by a light bulb. When doing this, care must be taken to ensure that the sand or other material remains wet.
Feeding the babies. Lizards eat small insects, spiders, enchitraids, and scraped meat. Young chameleons need fruit flies.
Transportation of reptiles. You must always be very careful not to harm the transported animal, yourself and others. Never forget the danger of overheating or hypothermia during transport. Take care not to miss the animal upon arrival home - the container should always be opened in a securely closed area.
Wide-mouthed vessels. Transparent plastic containers are recommended for the transport of small, fragile reptiles. These vessels must have screw caps with holes drilled into them. (The holes should be made so that their protruding edges are turned outward, and any irregularities are removed with a file.) Cans with tight-fitting perforated lids can also be used. Never leave animal containers in the sun.
Pouches. The cloth bag is suitable for carrying snakes and some other reptiles. You can use a sturdy pillowcase or make a bag out of unbleached fabric by sewing the edges securely on a typewriter. Once the reptile is inside the bag, tie the top of the bag with a strong knot. Be careful not to hurt any reptiles that may be crawling inside the pouch. Small, fragile animals are best placed with their bag in a ventilated box, even for small shipments.
Shipping reptiles. First, find out all the legal restrictions and rules of transport companies. Reptiles are usually shipped in jars or bags placed in strong, ventilated crates lined with crumpled newsprint. The crate must be labeled "Live Cargo" and include the scientific and common name of the animal. In case of an emergency, include a phone number.
Diseases of lizards:
1 Damage to the front of the head. Contact a veterinarian.
2 Ulcerative stomatitis. Isolate. Contact a veterinarian.
3 Rickets (deformity or weakness of the jaws and teeth or paralysis of the hind limbs). Multivitamins and sunshine. Contact a veterinarian.
4 Refusal of food. Force-feeding (using a syringe).
5 Infestation with ticks. Hang a paper strip with repellent in the cage (out of the reach of lizards!).
Frilled Lizard (Chlamydosaurus kingi)
| Value | Total length - up to 80 cm |
| signs | The body is pinkish or dark gray above with dark transverse stripes on the back and tail. Around the neck is a wide, serrated collar, or cloak, interrupted only at the back of the head and deeply dissected in the throat area. In males, the front collar is brightly colored with numerous pink, black, orange, brown, blue and white spots, and the chest and throat are jet black. |
| Nutrition | Various invertebrates, as well as small mammals and reptiles |
| reproduction | The female lays from 5 to 14 eggs in the ground, from which young lizards appear after about 2-3 months. |
| habitats | Northern and North Western Australia; lives in trees but willingly descends to the ground |
Spindle (Anguis fragilis)
Madagascar day gecko (Phelsuma madagascariensis)
| Value | Body length 23cm |
| signs | The body is of an intense velvety green color, large, irregularly shaped bright red spots on the back, turning into wide longitudinal stripes of the same color on the sides of the head. |
| Nutrition | Insects, spiders and other arthropods; hunts during the day |
| reproduction | Lays eggs in late spring or summer, usually 2 eggs each in a strong shell, 15 mm in diameter; usually laying several times a year; small geckos hatch in 2-4 months, their length is 3-4 cm |
| habitats | Inhabits Madagascar, its neighboring islands off the east coast of Africa, and the Andaman Islands off the coast of South Asia; nestle on tree trunks |
Arizona Chukwalla
| Value | Body length 14-20 cm |
| signs | Large, flat-bodied lizard; legs are thick, fingers are long and thin; a tail with a wide base and a blunt tip; males have a darker head, chest and shoulders, gray and brown spots; the rest of the body is rufous or light gray; in females and young animals, transverse stripes on the body and tail; in general, the color changes depending on the intensity of the sun's rays - darkens or brightens |
| Nutrition | Various desert herbs and insects |
| reproduction | Clutch of 5-16 eggs; June to August |
| habitats | Semi-deserts and deserts, rocky and rocky areas; western and southwestern North America, including Mexico |
Tanganyika Chameleon (Chamaeleo deremensis)
| Value | Total body length 11-12 cm |
| signs | The coloration is most often inconspicuous; sometimes dark green, yellowish-brown or green with rusty-brown spots; when too hot, dull yellow; the male has 3 conspicuous horns at the end of the muzzle; females usually have only one short horn, as if a continuation of the muzzle, and two weak outgrowths under the eyes |
| Nutrition | Insects and other small animals |
| reproduction | 10-20 cubs per litter; the cub is born in a thin egg shell, which it immediately breaks, its length is 5-6 cm (of which 2-2.5 cm is the tail) |
| habitats | Savannah; mountains of east africa |
General characteristics of the lizard suborder (SAURIA)
About 3,300 species of reptiles of various shapes and sizes (from 3.5 cm to 4 m; weight up to 150 kg). Some are legless. Ways of movement - from swimming (marine iguanas) to gliding (flying dragon). Food is varied - from small invertebrates to wild pigs and deer (giant monitor lizard). The skin is covered with horny scales. Many are capable of autotomy (tail drop). Well-developed vision (many distinguish colors), hearing (some make sounds), touch, parietal eye.
- · Gecko family - 600 species from 3.5 to 35 cm long. They inhabit tropical and subtropical regions. They lead a nocturnal lifestyle. The fingers are equipped with devices that allow geckos to stay on sheer vertical surfaces.
- · iguana family - 700 species from 10 cm to 2 m long. They inhabit the western hemisphere from southern Canada to southern Argentina. In arboreal forms, the body is laterally compressed, while in terrestrial forms, it is flattened in the dorso-ventral direction. Marine iguanas are semi-aquatic.
- · Agama family - about 300 species, close to iguanas, occupying ecological niches in Eurasia, Africa and Asia, similar to those of iguanas in America. They lead an arboreal lifestyle, inhabiting rocks, steppes and deserts. Representatives: steppe, Caucasian agamas, roundheads.
- · a family of real lizards - about 170 species distributed in Europe, Asia and Africa. In our region there are nimble and viviparous lizards.
- · spindle family - 80 species of legless or limbless lizards found on all continents. We meet yellowbell and spindle.
- · monitor lizard family - 30 species of the largest modern lizards. Distributed in Africa, Asia, the Malay Archipelago, Australia. From small (20 cm) to giant (4 m) monitor lizards. The gray monitor lizard and the giant monitor lizard occupy the ecological niche of large predatory animals that are absent in these habitats.
Lizards are the most numerous and widespread group of modern reptiles. The appearance of lizards is extremely diverse. Their head, body, legs and tail may be modified to some extent and deviate considerably from the usual type familiar to everyone. In some species, the body is noticeably compressed from the sides, in others it is valky or flattened from top to bottom, in others it is cylindrically shortened or elongated, like in snakes, from which some lizards are almost indistinguishable in appearance. Most species have two pairs of developed five-fingered limbs, but in some cases only the front or back pair of legs is preserved, and the number of fingers can be reduced to four, three, two and one, or they are completely absent. Most lizards are characterized by incomplete ossification of the anterior part of the skull, the presence of an sometimes incompletely closed upper temporal arch, a strong fusion of the upper jaws with the rest of the cranial bones, and the presence of special columnar bones connecting the roof of the skull to its base. The jaws of lizards are equipped, as a rule, with well-developed single-apex or multi-apex teeth, which are attached from the inside (pleurodont) or to the outer edge (acrodont teeth). Often there are also teeth on the palatine, pterygoid, and some other bones. Often they are differentiated into false canines, incisors and molars.
The language of lizards is extremely diverse in structure, form, and partly in the function it performs. Wide, fleshy and relatively inactive in geckos and agamas, it is strongly elongated, deeply forked, very mobile and able to be drawn into a special vagina in monitor lizards. The bifurcation of the tongue observed in many species, combined with its high mobility, is associated, in addition to touch, also with the function of the Jacobson organ that opens inside the mouth. A short and thick tongue is often used when capturing prey, and in chameleons it is thrown far from the mouth for this. The skin of lizards is covered with horny scales, the nature and location of which varies greatly, which is of decisive importance for taxonomy. In many species, large scales located on the head and other parts of the body increase to the size of scutes, each of which receives a special name. Often on the head and body there are tubercles, spikes, horns, ridges or other horny outgrowths formed by modified scales and sometimes reaching considerable sizes in males. Some groups of lizards are characterized by the occurrence under the scales of the body and head of special bone plates - osteoderms, which, articulated with each other, can form a continuous bone shell. In all species, the upper horny layer of the scales is shed during periodic molts and is replaced by a new one. The shape and size of the tail is very diverse. As a rule, it gradually becomes thinner towards the end and differs in considerable length, noticeably exceeding the body and head combined. However, in some cases it is shortened like a blunt cone, thickened at the end in the form of a radish, flattened spatulately, or has another unusual shape. More often oval or round in cross section, it is often compressed in a horizontal or vertical plane in the form of an oar. Finally, in a number of lizards, the tail is tenacious or capable of twisting like a spiral. Many lizards have the ability to autotomy. The fracture occurs along a special non-ossified layer across one of the vertebrae, and not between them, where the connection is stronger. Soon the tail grows back, but the vertebrae are not restored, but are replaced by a cartilaginous rod, which is why a new separation is possible only higher than the previous one. Often the torn tail is not completely separated, but a new one nevertheless grows, resulting in the appearance of two-tailed and multi-tailed individuals. It is interesting that in many cases the scales of the reconstructed tail differ from the normal one, and moreover, it has features of more ancient species. The dry skin of lizards is devoid of glands, but some roundheads (Phrynocephalus) have real skin glands on their backs, the function of which is not entirely clear. In representatives of a number of families, on the lower surface of the thighs, the so-called femoral pores are arranged in rows - special iron-like formations, from which columns of hardened secretion protrude in males during the breeding season. In other species, such formations are located in front of the anus or on its sides, respectively, called the anal and inguinal pores.
The smallest known lizards (some geckos) reach a length of only 3.5-4 cm, while the largest monitor lizards grow at least up to 3 m, weighing 150 kg. As a rule, males are larger than females, but in some cases, females, on the contrary, are noticeably larger than males. The eyes of lizards are in most cases well developed and protected by eyelids, of which only the lower one is movable, while the upper one is greatly shortened and usually loses its mobility. Along with this, in many species, the moving eyelids are replaced by a solid transparent shell covering the eye like a watch glass, like in snakes. On the example of a number of species from various systematic groups, it is easy to trace the gradual stages of the transition from opaque separate eyelids to the appearance of a first transparent window in the still mobile lower eyelid and further to the complete fusion of the lower eyelid with the upper one and the formation of an already immovable window in it. Such fused eyelids are present in most nocturnal lizards - geckos, a number of legless and burrowing species, as well as in some skinks and other lizards, as well as a diurnal and nocturnal lifestyle. Nocturnal lizards, as a rule, have significantly enlarged eyes with a pupil in the form of a vertical slit with straight or sawtooth cut edges. In the retina of the eyes of diurnal lizards there are special elements of color vision - cones, thanks to which they are able to distinguish all colors of the solar spectrum. In most nocturnal species, light-sensitive elements are represented by rods, and the perception of colors is not available to them. As a rule, lizards have good hearing. The tympanic membrane may be located openly on the sides of the head, hidden under the scales of the body, or may be completely overgrown with skin, so that the external auditory opening disappears. Sometimes it, together with the tympanic cavity, is reduced, and the animal is able to perceive sound only in a seismic way, that is, by pressing its whole body against the substrate. Most lizards emit only a dull hiss or snort. More or less loud sounds - squeaking, clicking, chirping or croaking - are capable of producing different geckos, which is achieved using the tongue or rubbing horny scales against each other. In addition to geckos, some sand lizards (Psammodromus) can also “squeal” quite loudly. The sense of smell is less developed than other senses, but some lizards may well find prey by smell. The nostrils of many, especially desert species, are closed with special valves that prevent sand from entering the nasal cavity. Some lizards have a well-developed sense of taste and willingly drink, for example, sugar syrup, choosing it among tasteless solutions. However, their taste sensitivity to bitter substances is negligible. Many lizards have tactile hairs formed from keratinized cells of the upper layer of the skin and regularly located along the edges of individual scales. In different places of the trunk and head, in addition, special tactile spots are often located, on which sensitive cells are concentrated. Many lizards have a so-called third, or parietal, eye, usually noticeable as a small light spot in the center of one of the scutes covering the back of the head. In its structure, it somewhat resembles an ordinary eye and can perceive certain light stimuli, transmitting them along a special nerve to the brain. The coloration of lizards is extremely diverse and, as a rule, harmonizes well with the environment. In species that live in deserts, light, sandy tones predominate; lizards living on dark rocks often have a brown, almost black color, and lizards living on tree trunks and branches are dotted with brown and brown spots resembling bark and moss. Many woody species are colored in the color of green foliage. A similar coloration is characteristic of a number of agamas, iguanas and geckos. The general coloration of the body largely depends on the nature of the pattern, which can be composed of individual symmetrically located spots, longitudinal or transverse stripes and rings, rounded eyes, or spots and specks randomly scattered throughout the body. In combination with the color of the main background of the body, these patterns further camouflage the animal in the surrounding area, hiding it from enemies. Diurnal species are characterized by very bright reds, blues and yellows, while nocturnal species are usually more uniformly colored. The coloration of some lizards varies significantly depending on sex and age, with males and juveniles usually more brightly colored. A number of species tend to quickly change color under the influence of changes in the environment or under the influence of internal states - excitement, fright, hunger, etc. This ability is inherent in some iguanas, geckos, agamas and other lizards.
Distribution and lifestyle.
The maximum number of lizard species lives in the tropical and subtropical zones of the globe, there are fewer of them in countries with a temperate climate, and the farther north and south, the more their number is declining. For example, only one species reaches the Arctic Circle - the viviparous lizard. The life of some lizards is closely connected with water, and although there are no real marine forms among lizards, one of them, the Galapagos iguana (Amblyrhynchus crislatus), penetrates the coastal waters of the ocean. In the mountains, lizards rise to the level of eternal snows, living at an altitude of up to 5000 m above sea level. Under specific environmental conditions, lizards acquire the corresponding features of specialization. So, in desert forms, special horny scallops develop on the sides of the fingers - sandy skis, which allow you to quickly move along the loose sand surface and dig holes. Lizards living in trees and rocks usually have long and prehensile limbs with sharp claws and often a prehensile tail that aids in climbing. Many geckos that spend their whole lives on vertical surfaces have special extensions on the underside of their fingers with tiny tenacious hairs that can attach to the substrate. In many limbless and burrowing lizards, the body is elongated serpentine. Such adaptations to certain living conditions in lizards are extremely different, and almost always they concern not only the features of the external structure or anatomy, but also affect many important physiological functions of the body associated with nutrition, reproduction, water metabolism, rhythm of activity, thermoregulation, etc. e. The optimal environmental temperature, most favorable for the life of lizards, lies in the range of 26--42 ° C, and in tropical and desert species it is higher than in the inhabitants of the temperate zone, and in nocturnal forms, as a rule, lower than in daytime . When the temperature rises above the optimum, the lizards hide in the shade, and when the limit temperatures are established for a long time, they completely stop their activity, falling into the state of the so-called summer hibernation. The latter is often observed in desert and arid regions in the south. In temperate latitudes, lizards leave for wintering in autumn, which in different species lasts from 1.5-2 to 7 months a year. Often they overwinter several tens or even hundreds of individuals in one shelter.
In lizards, the transition from real crawling on the belly to a gradual lifting of the body above the substrate and, finally, to movement with the torso raised high on the legs is clearly traced. The inhabitants of open spaces tend to move at a fast trot, and many of them switch to running on two legs, which is observed not only in exotic, but also in some species of our fauna. It is curious that the South American iguana Basiliscus americanus can even run short distances in this state through the water, slapping its hind legs on its surface. The ability to run fast is combined, as a rule, with the presence of a long tail, which plays the role of a balancer, as well as a rudder for turns on the run. Many geckos move in very short dashes, staying in one place for a long time. Arboreal species develop the ability to climb, which often involves a prehensile tail. Finally, some specialized forms, such as flying dragons (Draco), are capable of gliding flight due to skin folds on the sides of the body, supported by highly elongated ribs. Many lizards jump well, grabbing prey on the fly. Some desert species have adapted to "swimming" in the thickness of the sand, in which they spend most of their lives.
Most lizards are predators, feeding on all kinds of animals that they are able to grab and overpower. The main food of small and medium-sized species are insects, spiders, worms, molluscs and other invertebrates. Larger lizards eat small vertebrates - rodents, birds and their eggs, frogs, snakes, other lizards, and carrion. A smaller number of lizards are herbivores. Their food consists of fruits, seeds and succulent parts of plants. The lizards slowly sneak up on the prey and then grab it in the final throw. As a rule, the prey is eaten whole, but may be preliminarily torn apart by the jaws. Like other reptiles, lizards are able to remain without food for a long time, consuming the nutrient reserves deposited in the fat bodies located in the body cavity. In many species, in particular in geckos, fat is also deposited in the tail, the size of which is greatly increased. Lizards drink water by licking it with their tongue or scooping it up with their lower jaw. Desert species are content with water in the body of the prey they eat, and in some of them it can accumulate in special sac-like formations located in the abdominal cavity. In desert iguanas of the genus Sauromalus, on the sides of the body under the skin, there are special lymphatic sacs filled with a gelatinous fluid, which largely consists of water accumulated during rains and then slowly consumed during a long drought.
The lifespan of lizards varies greatly. In many relatively small species, it does not exceed 1-3 years, while large iguanas and monitor lizards live for 50-70 years or more. Some lizards survived for 20 - 30 and even 50 years in captivity. Most lizards benefit by eating a significant amount of harmful insects and invertebrates. The meat of some large species is quite edible, which is why they are often the object of a special trade, and the skin of these reptiles is also used by humans. In a number of countries, the capture and extermination of some lizards is prohibited by law. Currently, about 4000 species of various lizards are known, usually united in 20 families and almost 390 genera.
The bearded agama (Pogona vitticeps) is a lizard that even a novice terrariumist can have. Nature endowed this creature with an amazing appearance and sufficient unpretentiousness for life at home. The bearded dragon is native to the Australian continent. At one time, the Australian authorities very strictly controlled the export of representatives of the local fauna, but still the relatives of the agama got beyond the mainland and began to successfully breed in other territories that were quite suitable for them in terms of habitat conditions. The bearded agama is amazing not only in its appearance, but also in the name directly associated with it. The Latin word Pogona in translation just means the presence of a beard, and vitticeps has an even more bizarre meaning - “bulb headband”. So the Latin name of the lizard indicates the presence of leathery spikes around the ears, on the head and throat of the agama. These spikes just imitate a beard. The British, because of this sign, even called the agama the bearded dragon - the central bearded dragon. And another unique ability of the bearded dragon is to change color when the lizard is frightened or worried. In this state, the bearded agama brightens, and its paws acquire a bright yellow or orange hue. The color of the lizard can also change depending on the ambient temperature.
tree agama
Already from the name of the tree agamas of the species Agama atricollis it is clear that nature, for sure, has adapted these lizards to an arboreal lifestyle. And above all, she gave them a patronizing coloration. Try to see the tree agama in the lush greenery of the tropical African forest - you are unlikely to succeed. Its variable brownish, olive or green body easily merges with foliage or tree bark, and its elongated shape can resemble anything - a protruding branch, an outgrowth on a trunk, or a piece of the same bark. The sharp claws of the tree agama help it deftly move through the trees. But there are also atypical representatives of Agama atricollis, for example, with a bright blue head. By the way, these lizards are excellent camouflage. Despite the incredulity and not the easiest taming, they like to keep tree agamas in terrariums. True, this is possible only if they are provided with suitable conditions - temperature, humidity, feed. Tree agamas are rather capricious creatures and can easily wither away if something in the environment is not to their liking, that is, not for health. And do not expect devotion and affection from the lizard, it is not easy to make contact and at first it can be afraid of the owners, and after getting used to ignore it.
bengal monitor lizard
The Bengal monitor lizard (Varanus bengalensis) is a reptile that has a body size of up to 2 meters, as a rule, on average it does not exceed 170 cm. These animals have a slender body and a narrow, noticeably pointed head in front. Their tail is of moderate length, laterally compressed and has a low double keel along its upper edge. The body of monitor lizards is dark olive in color, covered on top with numerous speckles and round yellow spots. They are transverse lines. Adult representatives of this species are uniformly colored yellow, brownish-olive or brownish-gray, on which dark spots are barely distinguishable.
Cape monitor lizard
The Cape monitor lizard is also called the Bosca monitor lizard or the steppe monitor lizard (lat. Varanus exanthematicus) is a species of reptile from the monitor lizard family. This name of this species is erroneous, since this animal does not live in the Cape Mountains, but since it was first brought to Europe and described from South Africa, this name has stuck with it to this day.
Subspecies of this lizard are not distinguished. However, some herpetologists in their works describe 4 subspecies based on their habitat, but almost all taxonomists recognized them as invalid, and the species is considered integral.
These animals in adult form have a body length with a tail of 80 - 110 cm and up to 2 meters. Their body is atypical for monitor lizards, as it is rather overweight, but it fully corresponds to the life activity that the animal leads. That is, it is aimed at the endurance of the body and saving vital energy, and not at climbing trees and diving in water.
Cape monitor lizards have a short body and muzzle, it has obliquely set nostrils, shaped like slits, located very close to the eyes. These animals have short fingers with very large claws. The body of the lizard is covered with small scales, the tail is laterally compressed and has a double crest on the upper edge. The color of these reptiles has a gray-brown gamut with yellow stripes and spots. The lower side of the body of the monitor lizard is lighter than the back, the throat is yellowish-white, and brown and yellow rings are pronounced on the tail.
Komodo monitor lizard
The Komodo monitor lizard got its name from the fact that its habitat is the small island of Komodo in Eastern Indonesia, where it was described as a separate species in 1912. These reptiles have hardly changed over the past 2 million years. They take their origin from ancient snakes, having inherited from them a poisonous gland.
Komodo dragons are the largest reptiles on earth. Their dimensions can reach up to 3 meters in length with a weight of 150 kg. Wild monitor lizards are significantly inferior in size to their relatives, which are kept in captivity.
Juveniles of this species are quite brightly colored. From above, they are of a beautiful light chestnut color, which smoothly turns into green-yellow on the nape and neck, and carrot-orange on the shoulders and back. According to such colors, reddish-orange spots and rings are arranged in transverse rows on the body of the animal, which can merge into continuous stripes on the neck and tail. Over time, the color of monitor lizards changes to a uniform dark brown color, on which dirty yellow speckles can sometimes be found.
Nile monitor
The Nile monitor lizard (Varanus niloticus) is another one of the huge number of representatives of lizards.
In length, these animals can reach up to 2 meters, although such individuals are very rare. As a rule, the body size of a monitor lizard is 1.7 meters, of which 1 meter falls on the tail. In reptiles of this species, the tail is laterally flattened and equipped with a longitudinal keel (crest) on top. On the head there are no longitudinal rows of wide scales above the eyes, the nostrils are round and set closer to the anterior margin of the eye. The teeth of monitor lizards are cone-shaped in front, and with blunt crowns in the back.
The body color of the lizards is a dark yellowish-green gamut, against which there is a beautiful pattern of irregular transverse stripes formed by small yellow specks and spots. Between the shoulders and groin are horseshoe-shaped yellow spots, and in front of the shoulders is a black semicircular stripe. The color of the tail in its lower part is yellow with transverse stripes, and the first aunt of the tail has yellow-green rings.
striped monitor lizard
The striped monitor lizard (Varanus salvator) is a species of animal that belongs to the class of reptiles. It has many names, depending on where it is distributed. On the island of Bali, striped monitor lizards are called "Alyu", and on the island of Flores - "Veti". In other areas of Malaysia and Indonesia, these animals are called "Biawak Air" by the local population. In Thailand, they are called nothing more than “Khiah”, but more often they use the term “Tua-nguyen-tua-tong”. In Sri Lanka, striped monitors are called "Karabaragoya", while in Bengal they are called "Ram godhika", "Pani godhi" or "Pani goisap". In the Philippines, these monitors are called "Halo", but the most commonly used name is "Bayavac".
monitor lizard gray
The gray monitor lizard (Varanus griseus) is a representative of the lizard suborder of the reptile class. The size of an adult animal, together with the tail, can reach a length of 150 cm, and weight up to 3.5 kg. The body of this animal is massive, equipped with strong legs with curved claws on the fingers. Like most monitor lizards, the gray monitor lizard has a very strong and long rounded tail. The color of the scales merges with the surrounding background, which is a good means for hiding from enemies and for catching prey, because not every animal is able to recognize the body of an animal that is grayish-brown with a reddish tinge, which hid on the steppe plain. The lizard has dark spots and dots scattered all over its body, and almost parallel stripes run across the back and tail of the same color. On the head of the reptile are curved nostrils that open near the eyes. Such an anatomical structure will make it easier for the animal to explore holes, since the nostrils are not clogged with sand. The gray monitor lizard has strong and long teeth, in the oral cavity there are sharp, slightly recurved teeth that help to hold the victim. Throughout the life of the animal, they are erased and replaced with new ones.
Madagascar day gecko
Among the representatives of the tropical fauna there are a lot of truly beautiful animals, often painted in amazingly bright colors. Perhaps this is due to the fact that the very nature of the tropics is distinguished by a riot of colors. For example, in tropical latitudes there are exotic birds painted in incredible shades, as well as exotic lizards, one of which will be discussed in this article. The Madagascar day gecko (Phelsuma madagascariensis) deserves to be known not only to herpetologists and avid terrariumists. Although among lovers of exotic reptiles, he is rightfully called a veteran of terrariums. What is so unusual about the daytime Madagascar gecko? First of all, it is a bright color of the body. Moreover, the colors that nature gave to this lizard are unlikely to find analogues among artificially created shades. The body of the Madagascar day gecko is rich velvety green in contrast with large bright red spots along its back. Moreover, different representatives of the species may have a variable color, for example, be green-blue with several small red patches or pure green with a red stripe on the back. The Madagascar gecko is named diurnal in accordance with the daily rhythms of its life. The lizard lives, as the name suggests, only in Madagascar and belongs to the genus Felsum, endemic to this island. By the way, one of the most common and largest subspecies of the Madagascar day gecko is called Phelsuma madagascariensis grandis for its amazing appearance.
gecko madagascar
The Madagascar flat-tailed gecko, along with the common gecko, belongs to the celebrities of the tropical fauna because of its amazing appearance. It has the unique ability to change body color depending on ambient temperature and lighting. In the sun, the Madagascar gecko is deep green, and in the shade it can easily turn olive, brown, or even lose its green and put on a gray outfit. In bright sunlight, the body of the lizard takes on a lemon hue, but if you look at it against the light, the gecko is already aquamarine with a deep blue tail. This flat-tailed lizard is named for its wide and flattened top and bottom tail with serrated edges. And although the flat-tailed gecko is also classified as a Madagascar species, its habitat is not limited to this island. Broad-tailed lizards are also found in the Seychelles and Hawaii, however, scientists believe that reptiles were brought there, while Madagascar is their natural homeland. In size, flat-tailed Madagascar geckos are inferior to ordinary day geckos, but otherwise they have similar features. Which ones - read in the relevant sections. And of course, these lizards, like day geckos, are popular "exhibits" of terrarium collections. But in order for the flat-tailed gecko to always be alert, healthy and bright, it is especially necessary to maintain a suitable level of moisture in the environment. But for ordinary day geckos, this is not the most important indicator.