The topic of this article is reptiles. Species, origin, habitats, as well as some other facts about them will be presented in it.

The word "reptile" comes from a Latin term meaning "to crawl", "to crawl". This implies the nature of the movement of representatives of this class. It should be noted, however, that not all reptiles are animals that can only crawl. There are those who are good at jumping, running, swimming, and even practically flying, gliding like flying squirrels.

ancient reptiles

These animals lived long before the appearance of man on our planet. The reptiles living on Earth today are only relics (insignificant remnants) of a class that was very diverse and rich in the past. It's about about reptiles that reached their peak in (about 230-67 million years BC). Ancient reptiles were represented in a huge number of forms. Some of their species lived on land. One can note among them large predatory tarbosaurs and giant herbivorous brontosaurs. Others, such as ichthyosaurs, lived in the water. Still others could fly like birds. amazing world reptiles of antiquity has not yet been fully studied. Perhaps in the near future, scientists will encounter new discoveries.

In 1988, the remains of reptiles were discovered in Scotland. According to experts, these reptiles lived 340 million years ago. It was, as it turned out, the most ancient species of fossil reptiles known today. Their body was only 20.3 cm long.

Origin of ancient reptiles

Ancient reptiles evolved from ancient amphibians. This event was the next step in the adaptation of vertebrates to life on land. Today, amphibians and reptiles coexist. Amphibians are otherwise called amphibians, and reptiles are called reptiles.

Groups of modern reptiles

Reptiles (modern) include the following groups.

1. crocodiles. These are large animals with a lizard-like body. There are only 23 species of them, which include real crocodiles, as well as alligators, caimans and gharials.

2. beakheads. They are represented by just one type of hatteria called Sphenodon punctatus. These reptiles (a photo of one of them is presented below) according to appearance resemble (up to 75 cm) with a massive body, five-fingered limbs and large heads.

3. scaly. This group of reptiles is the most numerous. It includes 7600 species. These include, for example, lizards, the most numerous group of modern reptiles. This includes: monitor lizards, iguanas, scale-footed, skinks, agamas, chameleons. Lizards are a specialized species that leads a mainly arboreal lifestyle. Snakes also belong to scaly - legless reptiles, as well as amphisbaena - creatures with a worm-like body and short tail, resembling externally the head end. Amphisbaena are adapted for a burrowing lifestyle. They very rarely appear on the surface. These reptiles spend most of their lives underground or in the nests of termites and ants that amphisbaena feed on. They usually lack limbs. Representatives belonging to the genus Bipes have only front legs. They can move along earthen passages and tail first. Because of this, they are also called doubles. "Amphisbaena" is translated from Greek as "moving in both directions."

4. Another group - turtles. Their bodies are surrounded by shells from below, from the sides and from above. The shell includes the abdominal (plastron) and dorsal (carapace) shields, which are connected by a bone jumper or tendon ligament. There are about 300 species of turtles.

Together with mammals and birds, reptiles are combined into one group of higher vertebrates.

Where do reptiles live?

For the most part, reptiles lead a terrestrial lifestyle. These are creatures that prefer open landscapes warmed by the sun, including almost devoid of vegetation, waterless deserts. However, many turtles and all crocodiles live in rivers, lakes or swamps. Some snakes and some turtles also live permanently in the seas.

Reptile skin, unfortunately, is now used for the production of leather products. It is highly valued, and because of this, many representatives of reptiles suffer. Their future is in our hands.

Crocodile habitats

Crocodiles are common throughout the tropics. Basically, these reptiles are animals living in high-water swamps, lakes and rivers. They usually spend most of the day in the water. Crocodiles come to the coastal shallows in the morning, and also in the late afternoon, in order to bask in the sun. To salty sea ​​water relatively few species are tolerated. The combed crocodile swims especially far into the open sea - up to 600 km from the coast.

Habitats of tuatara and lizards

Tuataria today survived only on rocky islets located near New Zealand. A special reserve was created here for their sake.

Lizards are distributed almost throughout the planet, except for cold zones. Separate types in the mountains they rise to the border of eternal snow, for example, in the Himalayas - up to a height of 5.5 km above sea level. Most lizards lead a terrestrial lifestyle.

However, some of them climb trees or bushes, such as roundheads. Others may live permanently in trees and are capable of gliding flight. Agamas and geckos living in rocks can move along vertical surfaces. Also, some lizards live in the soil. They usually have no eyes, and their bodies are elongated. The sea lizard lives near the surf line. She has excellent swimming skills. She spends a lot of time in the water, eating seaweed.

Where do snakes and turtles live?

Snakes are everywhere on Earth, except for New Zealand, the polar regions and some oceanic islands. All of them swim well, there are even species that spend almost all or all of their time in the water. This sea ​​snakes. Their tails are compressed from the sides in a paddle-like manner. Due to the transition of snakes to a burrowing lifestyle, some of them have reduced their eyes and disappeared under the shields, and their tails have also shortened. These are narrow-mouthed snakes and blind snakes.

Freshwater and land turtles are found on many islands, as well as on all continents except Antarctica. Their habitats are very diverse. These are tropical forests, hot deserts, rivers, lakes and swamps, expanses of the ocean and coasts of the seas. All life sea ​​turtles carried out in water. They come ashore only to lay eggs.

The largest snakes

Most large snakes modern ones are anacondas (pictured above) and reticulated pythons. In length they reach 10 meters. In Eastern Colombia, a specimen of an anaconda was found, unique in size - 11 m 43 cm. The Brahmin blind is a body length of no more than 12 cm.

Sizes of crocodiles

The largest of the crocodiles are combed and Nile. In length, they reach 7 m. 1.2 m for females and 1.5 m for males is the maximum body length of a smooth-fronted caiman, the smallest among other species of crocodiles.

The largest and smallest turtles

The leatherback sea turtle is considered the largest of the modern turtles. Its length can exceed 2 meters. In the UK, on ​​the coast in 1988, the dead body of a male of this was found, which had a width of 2.77 m and a length of 2.91. musk turtle is the smallest among all species. On average, the length of her carapace is 7.6 cm.

Lizard sizes

Among the lizards, the Virginian round-toed geckos are considered the smallest. Only 16 mm is the length of their bodies (excluding the tail). No doubt the most large lizard is a Komodo monitor lizard (its photo is presented below).

The length of his body reaches three or even more meters. Living in Papua New Guinea, the thin-bodied monitor lizard of El Salvador reaches 4.75 m in length, but about 70% of its length falls on the tail.

Reptile body temperature

Like amphibians, reptiles do not have any kind of constant body temperature. Their life activity therefore depends to a large extent on the ambient temperature. For example, in dry warm weather they are especially active and at this time often catch the eye. On the contrary, in bad weather and cold they become inactive and rarely leave their shelters. At temperatures close to zero, reptiles fall into a stupor. That is why they are few in the taiga zone. There are only about 5 types of them.

Reptiles can control their body temperature simply by hiding from hypothermia or overheating. Hibernation, for example, allows reptiles to avoid cold weather, and daytime heat - night activity.

Breathing Features

Reptiles (a photo of some of them is presented in this article), unlike amphibians, breathe only with their lungs. Their lungs retain a bag-like structure, but in reptiles it is much more difficult. internal structure than amphibians. The folded cellular structure has the inner walls of their lung sacs. They resemble honeycombs. This significantly increases the respiratory surface in reptiles. Unlike amphibians, reptiles do not blow air through their mouths. However, for most of them, breathing of the so-called "suction" type is characteristic. They exhale and inhale air through the nostrils by constricting and expanding the chest. The act of breathing is carried out with the help of the abdominal and intercostal muscles.

However, in turtles, the ribs are immobile due to the presence of a shell, so the species belonging to them have developed a different method of ventilation than other reptiles. They drive air into the lungs by swallowing it or by making pumping movements with their front legs.

reproduction

Reptiles breed on land. At the same time, unlike amphibians, they have direct development, that is, without a larval stage. Reptiles typically lay yolk-rich large eggs with shell and amniotic (embryonic) membranes, which protect embryos from mechanical damage and water loss, and also provide gas exchange and nutrition. By the time of hatching, young reptiles reach a considerable size. These are already miniature copies of adults.

Reptiles, also known as reptiles, are a class of animals, usually terrestrial and vertebrate. It includes creatures such as turtles, crocodiles, lizards, snakes. Several centuries ago they were combined with amphibians, and now they are considered close to birds. Many reptiles are so unique that even a non-professional biologist will be interested in studying this class. What are reptiles? Photos and names, as well as some information about each, posted in our article, will help you figure it out.

Turtles

Perhaps with a shell - the most famous include both land and sea ​​views, they are found in many countries of the world, in addition, they are often kept at home even by those who are not a big fan of the exotic. Turtles appeared two hundred million years ago, it is believed that they evolved from primitive cotylosaurs. For a long time people liked them - they are practically not dangerous animals that evoke associations only with wisdom and calmness. Turtles are the only ones of the class that have a shell. Inside it is bone, and outside it is formed by horny tissue from many individual elements connected by plates. Land turtles they breathe with lungs, and water - with the help of the mucous membrane of the pharynx. In addition, these animals are unique in that they live longer than any other reptiles. The names of the oldest turtles include species such as the Carolina box tortoise, one of the reptiles captured was 130 years old. However, in wild nature more impressive figures are possible, but these individuals simply did not fall into the hands of researchers.

Chameleons

Perhaps many people, if they are asked to remember the names of reptiles, will not least say about these lizards. Unusual reptiles live on the branches of trees and are known for their unique camouflage. Their skin can change color according to their surroundings. Not surprisingly, chameleons are often kept at home. But it should be borne in mind that these are quite demanding reptiles. Photos and names are not all that you need to study before buying an exotic pet. First you need to deal with the conditions of detention - the chameleon needs a spacious terrarium and special lamps, a small pond and a tree, with excellent ventilation, and insects will have to be bought as food.

iguanas

Listing the names of reptiles that often become domesticated, one cannot fail to mention iguanas. It has become quite popular in last years, and the number of such pets can be measured in tens of thousands. But do not believe the information that keeping such a lizard is as easy as keeping a cat or a dog. The iguana is a finicky creature whose existence requires a lot of attention and Money. A lizard needs a special terrarium with a special temperature regime, as well as food from fresh vegetables, fruits and herbs. If all conditions are met, an iguana can grow up to five kilograms in weight! A unique feature of these creatures is molting - for many reptiles it happens quickly, and for them it sometimes takes weeks.

crocodiles

These animals are perhaps the most dangerous and frightening reptiles. The names may be different - crocodiles, gharials, alligators, caimans, but in any case, these are creatures from the same order. They originated from reptiles over fifteen meters in length and have been known since ancient times. Paleontologists have discovered footprints in Europe, North America, India and Africa. Now their sizes are much more modest, but they still remain the largest of the reptiles. Crocodiles spend most of their lives in the water, sticking out only their eyes, nose and ears. The tail and webbed feet make swimming an easy task, but only the combed variety can swim far out to sea. On land, they build nests, and sometimes they just get out to bask. The names of the reptiles of this order are different, but both the alligator and the crocodile have one thing in common - they are dangerous to humans. The reptile has incredible speed and a strong tail, so a sudden rush can cost the unwary traveler limbs or even life.

snakes

This is another reptile whose names are known to everyone. They differ from other reptiles in their long body shape, lack of paired limbs, eyelids, and external auditory meatus. Separate similar signs can be found in lizards, but all together - only in snakes. Now man knows their three thousand species. The body of a snake consists of three parts - head, body and tail. In some species, hind limbs have been preserved in rudimentary form. Many of them are poisonous, with channeled or furrowed teeth, which contain a dangerous fluid that comes from there. All internal organs are elongated, and the bladder is absent. The eyes are covered with a transparent cornea, formed from fused eyelids. In snakes leading a daytime lifestyle, the pupil is located transversely, while in nocturnal snakes it is vertical. Due to the reduced ear, only loud sounds are distinguished.

snakes

They can be very different, despite the fact that they belong to the same detachment. For example, snakes are snakes, although some believe that this is a separate species. In fact, these reptiles are simply not poisonous. However, they are snakes. They are distinguished by expressive scales with large ribs. Most snakes live near water bodies and feed on fish or amphibians. Rarely do they catch small mammal or a bird. Already swallows prey alive without killing it. When in danger, reptiles pretend to be dead, and when attacked, they secrete a liquid with an unpleasant odor. For reproduction, snakes look for a pile of plant debris, manure or wet moss.

monitor lizards

These are very famous reptiles, whose names are most often associated with the Komodo variety. In fact, there are seventy species of them, and they do not only live on certain islands. However, they all differ in impressive size - only short-tailed ones reach up to twenty centimeters, and all others can grow up to a meter. But, of course, Komodo are the largest, with a weight of one and a half centners and a length of three meters. That is why they are called dragons. Monitor lizards have tenacious and strong paws, a muscular long tail and large scales. Long tongue with a bifurcation at the end, lizards smell. The coloration is most often inexpressive, in gray, sandy and brown tones, although juveniles may be striped or spotted. Monitor lizards live in warm countries South or Africa and Australia. According to their habitats, they can be divided into two groups. The former prefers desert terrain and dry shrubs, while the latter keeps close to the water in the rainforest. Some monitor lizards like to spend time in trees.

geckos

These are reptiles whose species names are associated with the unique ability to stick to even the smoothest surfaces. A small gecko can climb up a vertical glass wall or even hang from the ceiling. In order to support its weight, the lizard can hold on with one foot. This feature has been surprising people for several millennia - Aristotle tried to unravel the skill of geckos.

Modern science knows the answer - the reptile's fingers have small ridges with thin bristles that help it stay on the surface due to the law of interaction between molecules.

reptiles- typical terrestrial animals and the main way of their movement is crawling, crouching on the ground. Key features the structure and biology of reptiles helped their ancestors leave the water and spread widely across the land. These features are primarily internal fertilization And oviposition, rich in nutrients and covered with a dense protective shell, which contributes to their development on land.

The body of reptiles has protective formations in the form scales, dressing them with a continuous cover. The skin is always dry, evaporation through it is impossible, so they can live in dry places. Reptiles breathe exclusively with the help of lungs, which, compared with the lungs of amphibians, have a more complex structure. intensive breathing with lungs became possible due to the appearance of a new part of the skeleton in reptiles - chest. The chest is formed by a series of ribs connected on the dorsal side to the spine, and on the abdominal side to the sternum. The ribs, due to special muscles, are mobile and contribute to the expansion of the chest and lungs during inhalation and their subsidence at the moment of exhalation.

With a change in structure respiratory system closely related changes in blood circulation. Most reptiles have a three-chambered heart and two circles of blood circulation (as in amphibians). However, the structure of the reptile heart is more complex. In his ventricle there is a septum, which, at the moment of contraction of the heart, almost completely divides it into the right (venous) and left (arterial) halves.

Such a structure of the heart and other than in amphibians, the location of the main vessels more strongly delimits the venous and arterial flows, therefore, the body of reptiles is supplied with blood that is more saturated with oxygen. The main vessels of the systemic and pulmonary circulations are typical of all terrestrial vertebrates. The main difference between the pulmonary circulation of amphibians and reptiles is that the skin arteries and veins have disappeared in reptiles and the pulmonary circulation includes only the pulmonary vessels.

About 8,000 are known today existing species reptiles found on all continents except Antarctica. Modern reptiles are divided into groups: primordial lizards, scaly, crocodiles And turtles.

Reproduction of reptiles

Fertilization in land reptiles internal: the male injects spermatozoa into the cloaca of the female; they penetrate the egg cells, where fertilization occurs. In the body of the female, eggs develop, which she lays on land (buries in a hole). Outside, the egg is covered with a dense shell. The egg contains a reserve nutrients, due to which the development of the embryo occurs. Not larvae emerge from the eggs, as in fish and amphibians, but individuals capable of independent life.

Primal Lizard Squad

TO primordial lizards refers to "living fossil" - tuatara- the only species that has survived to our time only on small islands near New Zealand. This is a sedentary animal, leading a predominantly nocturnal lifestyle and similar in appearance to a lizard. Hatteria in its structure has features that make reptiles related to amphibians: the vertebral bodies are biconcave, a chord is preserved between them.

Joy of the scaly

typical representative scaly - quick lizard. Its appearance indicates that it is a terrestrial animal: five-fingered limbs do not have swimming membranes, fingers are armed with claws; the legs are short, in connection with which the body, when moving, seems to be crawling along the ground, now and then in contact with it - groveling (hence the name).

lizards

Although the legs of the lizard are short, it can run fast, nimbly eluding pursuers into its burrow or climbing a tree. This was the reason for her name - nimble. The head of the lizard is connected to the cylindrical body with the help of the neck. The neck is poorly developed, but still gives the head of the lizard some mobility. Unlike a frog, a lizard can turn its head without turning its whole body. Like all land animals, it has through nostrils, and eyes have eyelids.

Behind each eye in a small depression is eardrum connected to the middle and inner ear. From time to time, the lizard protrudes from its mouth a long, thin, forked tongue at the end - the organ of touch and taste.

The body of the lizard, covered with scales, rests on two pairs of legs. The shoulder and thigh bones are parallel to the ground, causing the body to sag and drag along the ground. Ribs are attached to the thoracic vertebrae to form chest protecting the heart and lungs from damage.

Digestive, excretory and nervous system lizards are basically similar to the corresponding amphibian systems.

Respiratory organs - lungs. Their walls have a cellular structure, which greatly increases their surface. The lizard does not have cutaneous respiration.

The brain of a lizard is better developed than that of amphibians. Although it has the same five sections, but the hemispheres of the forebrain are larger in size, the cerebellum and medulla oblongata are much more massive.

The quick lizard is very widely distributed from the Black Sea to the Arkhangelsk region, from Baltic Sea to Transbaikalia. In the north, it gives way to a viviparous lizard similar to it, but more adapted to the cold climate. In the southern regions there are many different types lizards. Lizards live in minks, which in summer weather leave in the morning and evening, but no further than 10-20 m from the mink.

They feed on insects, slugs, and in the south - locusts, caterpillars of butterflies and beetles. During the day, one lizard can destroy up to 70 insects, plant pests. Therefore, lizards deserve protection as very useful animals.

The body temperature of the lizard is unstable (the animal is active only in warm time year), it falls sharply even if a cloud runs over the sun. With a longer decrease in temperature, the lizard loses mobility and stops eating. For the winter, she hibernates; can tolerate freezing and cooling of the body to -5 °, -7 ° C, while all the vital processes of the animal are significantly slowed down. Gradual warming returns the lizard to an active life.

In addition to the quick and viviparous lizard, there are many other types of lizards. Distributed in Ukraine and the Caucasus large green lizard: in desert areas - agama lizards with a long flexible and non-brittle tail.

predatory lizard gray monitor lizard desert dweller Central Asia. Its length is up to 60 cm. The monitor lizard eats arthropods, rodents, eggs of turtles and birds. The largest specimens of monitor lizards discovered by scientists herpetologists (a science that studies reptiles) on the island of Komolo reach 36 cm. In the northern regions, a legless lizard is common - spindle.

Chameleons

Chameleons in appearance they resemble medium-sized lizards, with a helmet-like outgrowth on the head and a body compressed from the sides. It is a highly specialized animal adapted to an arboreal lifestyle. His fingers are fused like pincers, with which he tightly wraps around the branches of trees. The long and prehensile tail is also used for climbing. The chameleon has a very peculiar eye structure. The movements of the left and right eyes are not coordinated and independent of each other, which gives some advantages when catching insects. An interesting feature chameleon is its ability to change the color of the skin - a protective device. Chameleons are common in India, Madagascar, Africa, Asia Minor and southern Spain.

snakes

The squamous order, in addition to lizards, includes snakes. Unlike chameleons, snakes are adapted for crawling on their stomachs and for swimming. In connection with wave-like movements, the legs gradually completely lost the role of organs of movement, only some snakes preserved their rudiments (boa constrictor). Snakes move by bending their legless bodies. Adaptability for crawling manifested itself in the structure internal organs snakes, some of them have completely disappeared. snakes don't have Bladder and just one easy one.

They see snakes badly. Their eyelids are fused, transparent and cover their eyes like a watch glass.

Among the snakes there are non-venomous and poisonous species. The largest non-venomous snake - boa- lives in the tropics. There are boas up to 10 m long. They attack birds and mammals, suffocate their prey by squeezing it with their body, and then swallow it whole. Large boas living in tropical forests are also dangerous to humans.

From non-venomous snakes widespread snakes. The ordinary one is already easily distinguished from poisonous snakes by two orange crescent spots on the head and round pupils of the eyes. He lives near rivers, lakes, ponds, eating frogs, and sometimes small fish, swallowing them alive.

Venomous snakes are viper, cobra, or spectacle snake, rattlesnake and etc.

Viper easily recognizable by the long zigzag dark stripe running along the back. In the upper jaw of the viper are two poisonous teeth with tubules inside. Through these tubules, a poisonous liquid secreted by the victim enters the wound. salivary glands snakes, and the victim, such as a mouse or a small bird, dies.

Destroying great amount mice and locusts, vipers are beneficial to man. However, their bites can cause long-term illness and even death in animals and even humans. The venom of snakes such as asian cobra, american rattlesnake.

The wounds formed when a person is bitten by a snake look like two red dots. A painful swelling quickly develops around them, gradually spreading throughout the body. A person develops drowsiness, cold sweat appears, nausea, delirium appear, in severe cases death occurs.

When bitten by a person poisonous snake urgent need to take first aid measures, remove excess poison near the wound with blotting paper, cotton wool or a clean cloth, if possible, disinfect the bite site with manganese solution, strictly protect the wound from contamination, give the victim strong tea or coffee, and ensure peace. Then get him to the hospital as soon as possible for an emergency injection of anti-snake serum. Where there are poisonous snakes, you can not walk barefoot. Care must be taken when picking berries, protecting your hands from snake bites.

Otrad crocodiles

crocodiles- these are large and most highly organized predatory reptiles, adapted to an aquatic lifestyle, live in tropical countries. Nile crocodile spends most of its life in the water, where it swims well, using a strong, laterally compressed tail, as well as hind limbs that have swimming membranes. The eyes and nostrils of the crocodile are elevated, so it is enough for him to put his head out of the water a little and he already sees what is happening above the water, and also breathes atmospheric air.

On land, crocodiles are not very agile and, in case of danger, rush into the water. They quickly drag their prey into the water. These are various animals that the crocodile lies in wait for at watering places. It can also attack humans. Crocodiles hunt mainly at night. During the day, often large and in groups lie motionless on the shallows.

Turtle Squad

Turtles differ from other reptiles in well-developed strong shell. It is formed from bone plates, covered on the outside with horny substance, and consists of two shields: the upper convex and the lower flat. These shields are connected to each other from the sides, and there are large gaps in front and behind the junctions. The head and forelimbs are exposed from the front, and the hind limbs from the back. Almost all aquatic turtles- predators, land - herbivores.

Turtles usually lay hard-shelled eggs on land. Turtles grow slowly, but they are among the centenarians (up to 150 years). There are giant turtles (soup turtle up to 1 m long. Weight - 450 kg. bog turtle- up to 2 m and up to 400 kg). They are commercial objects.

Meat, fat, eggs are used for food, and a variety of horn products are made from the shell. We have one kind of turtle - bog turtle lives up to 30 years. It hibernates for the winter.

Larval stage. Most reptiles are oviparous, although there are also viviparous species.

The size of reptiles ranges from the tiny gecko ( Sphaerodactylus ariasae), with a maximum body length of about 18 mm, to a combed crocodile ( Crocodylus porosus), which can reach 6 m in length and weigh more than 1000 kg.

Reptiles are common to all except. Depending on the species, they can live both on land and in water.

The modern classification distinguishes the following 4 orders of reptiles:

Detachment Beakheads

Beakheads ( Rhynchocephalia) - a detachment of lizard-like reptiles, which includes only one living genus of hatteria (tuatara). In turn, this genus Sphenodon) includes two types: Sphenodon punctatus And Sphenodon guntheri. According to some sources, the genus contains one species Sphenodon punctatus, which is divided into two subspecies - Sphenodon punctatus punctatus And Sphenodon punctatus guntheri. Representatives of the detachment live only in certain areas of New Zealand.

Despite the current lack of diversity, the detachment Rhynchocephalia included at the time a large number of genera and families, and it can be traced back to .

Tuatara grows up to 80 cm in length, from head to tail, and weighs up to 1.3 kg. This animal has a spiny crest along its back, which is especially pronounced in males. Tuataras are also distinguished by having a pronounced parietal eye (third eye). Animals can hear, although the outer ear is missing and tuatara have unique skeletal features.

Tuataras, like many of New Zealand's endemic animals, are endangered due to the loss and introduction of invasive species.

Squad Crocodiles

combed crocodile

Crocodiles ( Crocodylia) - a detachment of large, predatory reptiles, which includes 24 species. It includes: caimans, alligators, real crocodiles, gharials, etc. Crocodiles have powerful jaws with big amount conical teeth and short paws, with claws, and webbed toes. They have a unique body shape that allows the eyes, ears and nostrils to be above the surface of the water while most of the animal's body is submerged. The tail of crocodiles is long and massive. The skin of these reptiles is thick and covered with horny scales.

Crocodiles are the closest living relatives. A wide variety of fossil crocodiles have been discovered that lived over 200 million years, in the late. They are the largest and heaviest of modern reptiles. The largest representatives of the detachment are the Nile crocodile ( Crocodylus niloticus ) And combed crocodile (Crocodylus porosus) - reach a body length of up to 6 m and a mass of more than 1000 kg. For comparison, the smallest representatives of the order are smooth-fronted caimans ( Paleosuchus) and blunt-nosed crocodiles ( Osteolaemus tetraspis), have a length of about 1.7 m.

Crocodiles are found mainly in the low-lying, humid tropics and.

Troop Turtle

spurred turtle

Turtles ( testudines) - a detachment of reptiles, including about 300 species of turtles that live on land and in water (fresh and salty) on all continents except.

Earliest famous representatives This order existed about 220 million years ago, which makes turtles one of the oldest reptiles. Some species are endangered.

Turtles vary in size from less than 10 cm ( Sternotherus depressus) up to more than 2.5 m, (leatherback turtle - Dermochelys coriacea). Some species live in cold climates with a breeding season of only about three months; others live in tropical regions and breed all year round. Some turtles rarely see water, while others spend almost their entire lives in it, be it one small pond or one.

The shell is a unique adaptation of turtles that protects them from predators. He has various modifications and shapes to meet the protection, feeding and movement needs of turtles.

Squad order

Anaconda

scaly ( Squamata) - the most numerous detachment of reptiles, including lizards, chameleons, two-legged and snakes. Consisting of over 10,000 species, the squamates are also the second largest order in existence, after the perciformes (containing about 41% bony fish).

Team members are different skin consisting of horny scales. They also possess movable square bones. This is especially noticeable in snakes, which are able to open their mouths very wide to swallow relatively large prey.

Scaled ones come in a variety of sizes, from the 16 mm pygmy gecko ( Sphaerodactylus ariasae) up to more than 5 m green anaconda ( Eunectes murinus). The order also includes the now extinct mosasaurs, which reached a body length of about 15 m. Among other reptiles, squamates are most closely related to beakheads, which strongly resemble lizards.