Lepidoptera complete or incomplete transformation. The subtype is tracheal breathing. Types of insect development

1. Coleoptera squad (beetles)- the largest group of organisms, 400 thousand species have already been described, and discoveries continue. They are settled in all regions, withstand difficult environmental conditions - deserts, salt marshes, salt water, and the Zaitzevia thermae beetle was found in a thermal spring with a temperature of thirty degrees Celsius! The name was given to the detachment because its representatives have, instead of front wings, extremely dense leathery or sclerotized elytra without veins. The hind wings remain thin, retain their venation, and are used for flight. The mouth apparatus is gnawing. The larvae of beetles are worm-like, have three pairs of articulated legs.

1) Colorado beetle, whose expansion in fields and gardens began from Central America, adores the ground parts of the shoots of nightshades (potatoes, eggplants, peppers, tomatoes) and, without taking tough measures, is able to leave bare stems.

2) Chafer(like the related beetle), despite its beauty, it also skillfully harms - while its large larva grows and undergoes metamorphoses in the soil, it actively eats plant roots.

3) Bark beetles they lay eggs in the bowels of the wood, and the larvae are able to practically devour the tree. Quite often in the forests it is necessary to cut down entire sections of trees captured by bark beetles!

4) Barbel beetles notable for their long antennae, their larvae also eat wood, but do not live deep, under a layer of bark.

5) Against the background of these pests it looks pretty decent ground beetle, which exterminates some types of harmful insects.

6) Lacewing also "orderlies of vegetable gardens", their larvae very deftly manage with aphids - they inject a dissolving secret into the bodies and then suck out the liquid. True, the lacewings have to disguise themselves from the ants that "breed" aphids for their needs.

7) Gravedigger beetle recycles decomposed animal carcasses.

8) Dung beetle enriches the soil with nutrients, returning them with excrement.

9) ladybugs there are two, five and seven-point. Adults and their larvae feed mainly on aphids and spider mites.

10) Click beetles they breed thin, long wireworm larvae that eat potato tubers, and do not ignore beets with carrots.

11) Beet weevil kills up to 10 plants per day, its larvae eat beet roots with great appetite.

2. Flea squad- unites small wingless insects. Their body is laterally compressed, and their hind legs are elongated for high jumps. The oral apparatus is piercing and sucking. The larvae inhabit dirty rooms (for example, basements of houses), live in the crevices of walls and floors, and feed on decaying organic matter. Adults suck blood, endure severe diseases, first of all, relapsing typhus, the causative agent of which is spirochete. Rat flea carries the causative agents of the plague, it is because of it that half of Europe died out in the middle of the XIV century.

3. Lepidoptera squad or butterflies- unites flying insects with two pairs of wings covered with the smallest scales impregnated with chitin. Many butterflies are incredibly beautiful and collectible. At rest, diurnal butterflies fold their wings over their backs. In moths, the wings fold in the form of a roof. The sucking mouth apparatus is equipped with a long proboscis for obtaining nectar, but the larvae have a gnawing mouth. The larvae (caterpillars) are worm-shaped, their first three segments are paired legs, the rest are pseudopods. Furry caterpillars cabbage white they damage cabbage, radishes, radishes, and the birds cannot eat these larvae - they are poisonous, they are not afraid of anyone and therefore are defiantly colored in yellow-green and black. Pupae of cabbage whites can be seen on the bark of trees, on the walls of houses. Chrysalis silkworm wrapped in a cocoon of the longest (hundreds of meters!) silk thread and bred on an industrial scale. Oak silkworm not so valuable, its thread is coarser. Apple moth lays the larvae right inside the apples (although some people believe that an apple with a worm is much more natural than the "plastic" fruit in which no one lives). Moth- a household insect that has already become familiar, does not bite, but is able to eat a carpet, a fur coat, a woolen blanket. There is even some evidence that moths can eat synthetic fibers! Caterpillars winter scoops eat seeds sown in the fall in the soil, destroy seedlings, damage plant shoots at the soil level.

4. Diptera squad- its representatives retained only the front pair of wings, while the rear pair was modified into halteres with balance organs inside (mosquitoes, flies, biting midges, horseflies, midges, gadflies, mosquitoes, etc.). The oral apparatus of different species differ in structure. The larvae do not have legs, and their head is visually almost indistinguishable.

1) U house fly The larva is characterized by a white elongated body with segments; it drips on food with digestive juices and absorbs a semi-digested substrate. Mature flies have a rather wide flattened body, a hemispherical head and short antennae. Flies carry particles of dirt on their paws - it is with paws equipped with organs of touch that they feel all surfaces, "dig" into food debris encountered on the way. The organ of taste is located on the forelegs. The house fly only seems harmless, but in fact it spreads the causative agents of cholera, typhoid fever, dysentery, ascariasis, etc.

2) Mosquitoes being bloodsuckers, they are equipped with piercing-sucking mouthpieces. Male mosquitoes are innocent in front of a person, they do not bite and drink plant sap, and females suck blood, they need it for laying eggs. Mosquito larvae grow in stagnant waters, which is why there are so many mosquitoes in coastal water bodies. It is noteworthy that an ordinary mosquito positions its body parallel to the surface, and an malarial mosquito at a slight angle. But! The larva of an anopheles mosquito positions its body parallel to the surface of the water, but the larva of an ordinary mosquito - at an angle. Malaria mosquito lays eggs in water, equipped with swimming chambers. In the larva of the malaria mosquito, the body is articulate, elongated, without legs, the head, chest and abdomen are separate. In addition, it has simple eyes, antennae, setae on the chest and abdomen, spiracles at the end of the abdomen.

3) Autumn flare actively flies out at the end of summer, inflicts sensitive bites.

4) Blind- blood-sucking, large insects, are the scourge of freely grazing livestock, they carry anthrax.

5. Order Hymenoptera- its representatives have reached the highest evolutionary level among insects, are social animals: bees, wasps, ants, etc. They have two pairs of membranous wings, relatively small, and the back ones are smaller than the front ones. The chest and abdomen are connected by a narrow bridge. In females, the ovipositor is located on the abdomen, which can turn into a sting. The mouth apparatus is of a gnawing or gnawing-sucking type. In this order, polymorphism is often found, individuals of the same species are very different.

1) U bees there is a single large, sedentary queen, large big-eyed drones, which are busy only with her fertilization, and a host of small sterile females, worker bees. Why are bees called social insects? For example, a working female, upon returning to the hive "from the route", informs the comrades about the direction and distance of the flowers rich in nectar and pollen - she performs a "dance", making circles over the honeycomb and wagging her belly. The bee hive is built from wax secreted by special glands. In its empty cells, the queen lays thousands of eggs (and if the queen loses this ability, the bees expel or kill her). The worker bees feed the larvae with honey and pollen; by the way, the worker bee has a gnawing-licking type of mouth apparatus. Drones hatch from unfertilized eggs, from fertilized ones - queens and worker bees. To nurture a strong, fertile queen, she is fed with royal jelly.

2) Bumblebee- a larger insect than a bee, pollinates many plant species, in particular, meadow clover.

3) Riders- insects are graceful, slender, their abdomen is located on a thin stalk. With her ovipositor, the female bores the outer shell of the caterpillar and lays eggs inside.

4) Ants- builders of anthills, sometimes very large, with underground and aboveground parts. Ants hide in them at night and in bad weather, lay eggs, raise pupae. Worker ants are wingless, barren females, or soldier ants. Winged queens in the company of winged males go on a mating flight in the spring. After fertilization, young females descend to the ground, shed their wings, establish a new nest, and the males die after flight. Red forest ants living in one anthill are able to eat about 18 thousand insects per day - thus, they protect the forest from pests. Have horntail females have a long and hard ovipositor, with which they drill through the bark of trees and lay eggs in the holes made. Larvae sawflies feed on leaves. Trichogramma egg eaters lay eggs inside the eggs of 80 species of butterflies, and telenomuses- in the eggs of the bugs of harmful turtles.

Development with incomplete transformation is characterized by the fact that an insect emerges from the egg membranes, which is similar in structure to the adult, but much smaller in size. As a result of intensive nutrition, it grows, but the chitinized cover prevents an increase in linear dimensions and volume. This leads to molting, during which the chitinized cover is shed, which has become tight. Beneath it is a new soft cuticle that lies in folds.

After shedding the old cover, the new cuticle straightens out. The size of the animal increases. Having made several molts without the formation of a pupa, the animal reaches maturity, its wings develop, the sex glands mature, and the external genital appendages appear. This is how Orthoptera, lice, bedbugs, etc. develop.

Insects with incomplete transformation include representatives of the Orthoptera order: migratory locusts, filly, grasshoppers, crickets. They have mouth organs of a gnawing type, their front wings are long, narrow and thickened, and the rear ones are wide and soft.

The hind legs of Orthoptera are very well developed and much longer than the fore and middle legs; thanks to them, Orthoptera jump long distances.

Locusts are insects with incomplete transformation

The locust reaches a length of 5-6cm. She is very voracious, eats any plants. Constantly lives and multiplies in reed thickets. On the territory of the CIS, its habitats are the banks of the lower reaches of the Terek, Kuban, Ural, Amu Darya, and Syr Darya rivers. In late summer, the female locust lays eggs in the soil. They are glued together and form what is called a pod.

In spring, larvae hatch from eggs, similar in structure to adult insects, but a number of organs, including wings, are still underdeveloped. Such larvae are called foot locusts. The larvae grow, molt and develop into adult winged insects. Migratory locusts can fly long distances from their permanent habitats and cause enormous damage to crops of cultivated plants. The main method of locust control is the use of various poisons.

Insects with complete transformation, their role in human life

Let us consider the development of insects with complete transformation using the example of the May beetle. With this development, a larva emerges from the eggs, which sharply differs from the adult. With this form of metamorphosis, the larva molts several times as it grows. But in order to transform into an adult form (imago), it must go through the pupa stage.

In some insects, pupae are mobile, in others they are motionless. At this stage, the larval organs undergo complete restructuring. Most of the organs are destroyed. Only the nervous system, the rudiments of the gonads and special anlages - the imaginal discs - are preserved, due to which the organs of an adult insect are formed at the same time, but they remain in a compressed, folded state.

At the time when the adult form leaves the pupal integument, blood enters the compressed imaginal organs and they straighten out, take the form characteristic of an adult insect, after which chitin begins to be deposited and the integument of the body hardens.

Insects with complete transformation include representatives of the order Lepidoptera (butterflies), which have two pairs of wings. They got their name because their wings are covered with modified hairs - scales, which are often brightly colored and form characteristic "patterns" on the surface of the wings.

Butterflies are representatives of insects with full development

On the head of butterflies there are well-developed faceted eyes and a pair of antennae with olfactory organs.

The segments of the thoracic region are fixedly connected to each other. The pectoral legs are not very strong, sometimes thin and weak, but extremely tenacious. With the help of their legs, butterflies are held on flowers, plant stems, tree bark, etc.

Mouth organs in adult butterflies of the sucking type. They are transformed into a proboscis adapted to suck the nectar of flowers. The larvae, called caterpillars in butterflies, have gnawing mouth organs. Caterpillars feed on leaves, fruits, and other plant parts.

Caterpillars of butterflies have spinning silk glands, which secrete substances that freeze in the air into strong threads. Different types of caterpillars use these threads in different ways:

• Descend from the branches of trees;
• entangle shoots and leaves;
• build special covers in which larvae (moths) pupate;
• cocoons curl in which they pupate (real silkworms, etc.).

Butterflies attach their eggs to plant branches, tree bark, i.e. where their caterpillars feed. The organs of smell help butterflies find such plants. With the help of faceted eyes, butterflies not only distinguish color, but also determine the shape of objects.

Many butterflies (cabbage whiteworm, meadow moth, winter moth, oak silkworm, etc.) cause serious damage to agriculture and forestry.

Cabbage white (cabbage)

Caterpillars of cabbage whites, or cabbage, widespread, do great harm to cabbage. It was found that, although the cabbage caterpillars are clearly visible on cabbage leaves due to their variegated color and the ability to stick in groups, they are not subject to destruction, since they are inedible, which is combined with a warning coloration. The green color of caterpillars in many other species of butterflies is patronizing.

The caterpillar of the cabbage whites has a greenish color. On the sides of the body and on the back, she has yellow stripes and black dots. After the caterpillar grows up, it crawls onto a tree, wall, fence, etc., where it turns into a pupa. After leaving the pupa, the butterfly sits in one place for several hours, until its wings spread out and get stronger.

In the fight against cabbage whites, it is necessary to weed out weeds, collect and destroy cabbage caterpillars and eggs.

While the larval forms of butterflies bring significant harm, then the adult forms are of great benefit, pollinating many plant species. In addition, they serve as food for birds.

Silkworm

Among the many species of silkworms that have received this name due to the fact that their caterpillars turn into pupae in silky cocoons, the silkworm is of great importance - the only fully domesticated species of butterflies. The silkworm caterpillars are fed by the leaves of the mulberry tree (mulberry), which is the reason for the name of the insect.

In natural conditions, the silkworm does not exist. It was first domesticated by the Chinese at least 2.5-3 thousand years ago. The Arabs brought it to Europe in the 8th century. Currently, sericulture is widespread in many countries of the world, including the CIS (Caucasus, Central Asia, Ukraine). Man bred various breeds of silkworms, characterized by a large amount of silk in a cocoon (from 1 kg of raw cocoons, up to 90 g of raw silk are obtained).

Although silkworm butterflies have wings, as a result of domestication, these insects have lost the ability to fly. The silkworm does not feed in adulthood. Males have a thinner abdomen and feathery antennae. Fertilized females lay eggs, or grenou, after which they soon die. Grena is also obtained from butterflies at special stations, where it is stored and sent to silkworm farms.

The silkworm caterpillars are whitish and worm-shaped. At the end of the abdomen, they have a corneous appendage. They crawl relatively slowly. Caterpillars develop from 40 to 80 days. Cocoons are marinated with hot steam, dried, the threads are unwound and natural silk is obtained.

In our country, sericulture is an important branch of the national economy. Currently, work is underway not only to improve the silkworm breeds, but also to expand silkworm breeding in more northern regions.

Class 1. Primary tracheal. Sushi animals. They live in damp places under leaves, bark, stones. More common in the Southern Hemisphere. Because have signs of similarity with both annelids and arthropods, then they are an intermediate form between these groups of animals.

Class 2. Centipedes. The representative is the scolopendra inhabiting the Caucasus and Crimea. It feeds mainly on insects, but the bites are painful for humans.

Class 3. Insects. Polymorphic group, inhabitants of all spheres: air, water, soil. The number of described species is from 900,000 to more than 1 million. They form 27 orders and two subclasses: primary wingless and winged.

The first subclass includes insects, which, like their ancestral forms, initially did not have wings (silverfish, springtail).

Groups of winged insects are grouped depending on the form of metamorphosis - with complete or incomplete transformation.

Insects with incomplete transformation.

Order 1. Orthoptera: grasshoppers, crickets, locusts, bears.

Detachment 2. Cockroaches: black cockroach, Prussian, American cockroach.

Detachment 3. Praying mantises.

Detachment 4. Ghosts: stick insect, leaf beetles.

Order 5. Termites: "white ants".

Detachment 6. Hay-eaters: "book louse"

Detachment 7. Dragonflies: dragonfly - rocker.

Detachment 8. Mayflies.

Detachment 9. Vesnyanki.

Detachment 10. Puff lice: dog louse (does not feed on blood, but on various elements of the epidermis).

Detachment 11. Lice.

Order 12. Arthropod: cicadas, flies, scale insects, aphids.

Order 13. Hemiptera, or bugs.

Insects with complete transformation.

Order 1. Retinoptera: ant lion, lacewing.

Order 2. Beetles, or coleoptera: May beetle, ground beetles, water beetle, bark beetles, weevils, barbel beetle.

Order 3. Caddisflies: Phriganidae, stenophilus.

Order 4. Lepidoptera, or butterflies.

Order 5. Diptera.

Detachment 6. Fleas.

Order 7. Hymenoptera: bees, wasps, ants, wasps.

Insect development

After leaving the egg, the embryo, freed from the embryonic membranes, becomes the nymph of the first stage, or the larva, from which the postembryonic period of insect development begins.

Morphological changes that occur during development from the larva to the adult insect are called metamorphosis.

As a result of these changes, the insect in the later stages of development is often completely different from the early embryonic forms. An example is the transformation of a larva into a non-feeding stage - a pupa, preceding the appearance of an adult insect (imago). In many insects, the growth process includes periodic molting. Most insects molt at least 3-4 times a year, with more than 30 molts. On average, the number of molts is 5 - 6.

Incomplete metamorphosis characteristic of primitive winged insects. For the first time, their wings appear after the third molt in the form of small outgrowths. These wing rudiments increase in size with each subsequent molt, and at the last, preimaginal age, they can already cover several segments of the abdomen. In an insect of preimaginal age, the full development of imaginal structures occurs, and the adult insect appears as a result of the last molt fully formed. Such a metamorphosis can be called gradual, i.e. the wings develop gradually as external outgrowths.

Complete metamorphosis characterized by the development of wing buds inside the body up to preimaginal age, after which the wings are turned outward in the form of large appendages. This occurs during the non-nourishing stage, when imaginal structures are formed from tissues belonging to earlier stages. In insects with this type of development, three clearly distinguishable postembryonic phases are distinguished: a young form, or a larva that does not have wing buds; pupa, a resting form with wing buds, and an adult insect (imago).

The molting process can be divided into several stages:

An increase in the hypodermis, either due to cell division, or due to an increase in their volume, after which the cuticle (chitinous layer) is separated from the hypodermis.

a new epicuticle is formed on the surface of the "bare" hypodermis. A larval fluid is secreted between the new and old cuticles, which is still in an inactive state.

The epicuticle becomes impenetrable, the larval fluid becomes active, and the enzymes contained in it (chitinase and proteanase) dissolve the old cuticle. The products formed when the old cuticle dissolves are absorbed by the epithelial cells of the hypodermis and are used to build a new cuticle.

Relief from old cuticles. To do this, the insect contracts the abdomen, directing blood to the chest and inflating it until the cuticle bursts along the tear line. After the old cuticle breaks, the insect is released from it.

Immediately after molting, the new cuticle is stretched within a short time due to the ingestion of air or water by insects, resulting in an increase in body volume. An increase in blood pressure at this time also contributes to the stretching of the integument.

After stretching the cuticle, the cells of the hypodermis secrete a thin cement layer that retains its shape.

The insect class has two subclasses: primary wingless and winged.

TO subclass primary wingless Insects are insects whose ancestors never had wings (sugarcane, springtails, etc.). Silverfish lives in sheds, closets. basements. It feeds on decomposing substances, it is harmless to humans. In flower pots with excessive watering, wingless insects often appear - springtails. They feed on decayed plants or their lower plants. A reliable fight against them is to reduce watering.

Subclass of winged subdivided into insects with incomplete transformation and insects with complete transformation.

The distribution of species into orders is carried out taking into account such characteristics as the nature of development, features of the structure of the wings, the structure of the oral apparatus. The main features of some orders of insects are presented below.

Some signs of the most important orders of insects

Detachments	Development type	Number of pairs of wings	Oral apparatus	Wing development feature	Some representatives
Cockroach	With incomplete transformation	Two pairs	Gnawing	Elytra	Red and black cockroaches
Termites	With incomplete transformation	Two pairs	Gnawing	Mesh	Termite
Orthoptera	With incomplete transformation	Two pairs	Gnawing	Elytra	Locusts, grasshoppers, crickets
Lice	With incomplete transformation	No wings	Thrusting	Wingless	Head louse, clothes louse
Bedbugs	Louse	Two pairs	Thrusting	Elytra	Bug-turtle, bug-gladun, bug-water strider
Isoptera	With incomplete transformation	Two pairs	Thrusting	Mesh	Cicadas
Grandmas	With incomplete transformation	Two pairs	Gnawing	Mesh	Watch grandma, rocker grandma
Beetles, or coleoptera	With complete transformation	Two pairs	Gnawing	Elytra are firm	May beetle, Colorado potato beetle, gravedigger beetles, bark beetles
Butterflies, or Lepidoptera	With complete transformation	Two pairs	Sucking	Mesh with scales	White cabbage, hawthorn, silkworm
Hymenoptera	With complete transformation	Two pairs	Gnawing, lapping	Mesh	Bees, bumblebees, wasps, ants
Diptera	With complete transformation	1 pair	Prickly-sucking	Mesh	Mosquitoes, flies, gadflies, midges
Fleas	With complete transformation	No	Prickly-sucking	Wingless	Human flea, rat flea

Insects with incomplete transformation

The most common are: cockroach squad- a typical representative - red cockroach... The appearance of cockroaches in dwellings is a sign of slovenliness. They come out of their hiding places at night and feed on carelessly stored food, contaminating it. At the end of the abdomen, female cockroaches wear a brown egg "suitcase" - ootheca... They dump it in the trash. Eggs develop in it, from which larvae are born - small white cockroaches, similar to adults. Then the cockroaches turn black, molt several times and gradually turn into adult cockroaches.

Squad of termites- this includes social insects living in large families in which there is a division of labor: workers, soldiers, males and females (queens). Termite nests - termite mounds, can be of considerable size. So, in the African savannas, the height of termite mounds reaches 10-12 m, and the diameter of their underground part is 60 m. Termites feed mainly on wood, they can damage wooden buildings, agricultural plants. About 2,500 species of termites are known.

Orthoptera squad- most of the representatives of the order are herbivorous, but there are also predators. This includes grasshoppers, cabbage, locust... The green grasshopper lives in the grass in the meadows, in the steppes. Has a long clavate ovipositor. Kapustyanka - has burrowing legs, flies and swims well. Causes great harm to underground parts of garden plants, such as cucumbers, carrots, cabbage, potatoes, etc. Some locust species are prone to mass reproduction, then they gather in huge flocks and fly a considerable distance (up to several thousand kilometers), destroying all green vegetation on your way.

Squad of bedbugs- this includes known pests of agricultural crops - bug-turtle sucking out the contents of the caryopsis of cereal plants. Found in dwellings flea bug- a very unpleasant insect for humans. In fresh water bodies or on their surface, a water strider bug lives, feeding on insects falling into the water. Predatory bedbug attacks various invertebrates and fish fry.

Homoptera squad- all its representatives feed on plant juices. Many kinds aphids cause great harm to cultivated plants. Many Homoptera are carriers of viral plant diseases. This includes a variety of cicadas, the size of which is from a few millimeters to 5-6 cm. They live in the crowns of trees.

Grandma squad are exceptional predatory insects. Adults attack prey in flight. The best flyers. Their flight is highly maneuverable: they can hover in the air, be mobile and can reach speeds of up to 100 km per hour. This includes rocker head, patrol grandmother and etc.

Insects with complete transformation

Squad of beetles, or coleoptera, are the most numerous order of insects, up to 300,000 species. Beetles are common in a wide variety of terrestrial and freshwater environments. Their sizes range from 0.3 to 155 mm in length. Many beetles cause great harm to cultivated plants. One of the pests of potatoes and other plants is Colorado beetle brought to us from America. Kuzka beetle- a pest of cereals; Chafer- its larvae damage tree roots and potato tubers; beet weevil- affects sugar beets. It also includes bark beetles carving tunnels in the bark and bast fibers of valuable tree species, and the larvae goldfish and i live in dead wood, cause great damage to forestry.

Many beetles spoil food supplies: pea weevil, bread beetle, skin-eating beetle damaging leather, woolen products. A small beetle belongs to the order of beetles. tube-runner... The biology of these beetles is very interesting. In the springtime, the pipe-runner cuts the leaf in a special way up to the main vein. The incised part of the sheet fades and loses its elasticity. Then the beetle rolls the bag up and lays eggs there. Something like a cigar is formed. This is how the pipe-worker expresses concern for the offspring.

Some beetles feed on the remains of plants and animals and play the role of orderlies in nature, for example: pus beetles and coffins... Some can be used to control harmful insects. So, ladybug destroys aphids, and large green paint beetles- caterpillars.

Beetles are extremely beautiful, large in size, for example stag beetle, or stag, listed in the Red Book, reaches a length of up to 8 cm, its larvae develop in rotten stumps for about five years and grow up to 14 cm long. In reservoirs, beetles of various sizes and methods of feeding live - a swimming beetle, and a black water lover. The swimming beetle is a predator, the black water lover is herbivorous.

Butterfly squad, or lepidoptera, - representatives of this order differ in the varied colors of their wings. This includes hives, cabbage butterfly, silkworm and others. Among the species living in the Far East, there are very large moths, which in the wingspan correspond to the width of an unfolded notebook. Butterflies' wings are covered with modified hairs - scales that have the ability to refract light. The iridescent color of the wings of many butterflies depends on this phenomenon. The butterfly larvae are called caterpillars... They have a gnawing apparatus, a long body. Their salivary glands, in addition to saliva, also secrete silk threads, from which a cocoon is weaved before pupation. Adult butterflies are very good plant pollinators. Caterpillars of most butterflies are herbivorous, eating leaves of plants, cause significant harm, for example, cabbage whitelet, apple moth, goldtail, ringed silkworm, etc. The caterpillar of the room moth feeds on woolen products, damaging them, some caterpillars spoil flour and other food products.

Mulberry and oak silkworms- for a long time they have been bred by people in order to obtain silk (from cocoons). Many large butterflies are extraordinarily beautiful, for example swallowtail, Apollo and others. A large butterfly is very interesting night peacock, on the wings of which there are ocular spots. Its caterpillar is large, fleshy, green in color; before pupation, it weaves a cocoon the size of a hen's egg.

Large moths with acute-angled wings, characterized by a very fast flight - hawk makers, - are named so because they willingly feed on fermented and fragrant tree sap, especially birch sap, protruding on wounds and stumps.

Hymenoptera detachment- unites a variety of insects: bees, bumblebees, wasps, riders, sawflies etc. The lifestyle of these insects is varied. Some of them are herbivorous, as their larvae (very similar to caterpillars) cause great harm to grains and other plants, for example bread and pine sawflies... Sawfly larvae feeding on foliage become so similar to butterfly caterpillars that they are called false caterpillars. A striking device is the ovipositor of sawflies, which serves to cut out pockets in plant tissues, in which female sawflies hide eggs, thereby showing original care for the offspring.

Excellent plant pollinators are bumblebees... It is a social insect. The bumblebee family has only existed for one summer. Nests are built in mouse holes, hollows, squirrel nests, in birdhouses. The nest is built by the female, equipping wax cells in it for laying eggs. A supply of food is placed in the cell - a mixture of pollen with honey. The larvae that emerge from the egg eat food and after two to three weeks weave silk cocoons, turning into pupae. Working bumblebees, females and males hatch from pupae. By the end of summer, there are up to 500 bumblebees in large nests. In the fall, the old queen, males and workers die, and the young queen hides for the winter.

Lifestyle wasps looks like a bumblebee. They also exist for one summer. Wasps are beneficial by destroying harmful insects, and the damage from spoiling fruits by them is small. More harm from hornets(one of the species of swarm wasps): they gnaw the bark of young trees and eat bees. Having settled near the apiary, they kill thousands of bees over the summer.

Of the social insects of the Hymenoptera order, it is of great benefit honey bee... She is a wonderful pollinator of plants, and produces an exceptionally useful food product - honey, as well as wax, royal milk, widely used by humans in perfumery. medicine, for the manufacture of varnishes, paints, etc.

The bee family is a surprisingly complex whole in which all members of the family are very closely related to each other. Life and prosperity of the whole race are equally impossible without a queen and without drones, without working bees. Using knowledge about the life of all members of the bee family, beekeepers have learned how to create specialized houses for bees - hives, conditions for feeding bees (they are taken to those fields where honey plants are grown) and at the same time receive not only good quality honey, but also quantity ...

Representatives of the order Hymenoptera are used as a biological method for controlling harmful insects. These include various riders, as well as a trichogramma, which is artificially derived

Diptera squad... This includes the well-known insects: flies, mosquitoes, midges, gadflies, horseflies and other insects similar to them, possessing one pair of transparent wings. The second pair of wings became the so-called halteres. The common mosquito lives in swampy and damp areas. Mosquitoes are especially numerous in the middle of summer. The inhabitants of the taiga and tundra call their clusters vile... Mosquitoes can easily pierce human skin with stabbing mouths and suck blood. Worm-like mosquito larvae live in stagnant water. While feeding, the larvae grow, molt and turn into mobile pupae. Pupae of mosquitoes also live in water, they cannot feed, therefore they soon turn into an adult.

The malaria and common mosquito are distinguished by planting.

Common mosquito (squeak) keeps his body parallel to the surface on which he sits, and malarial- at an angle to it, raising the rear end of the body high. Anopheles mosquito lays eggs in a pond one by one, an ordinary mosquito - in packs, floating on the surface in the form of rafts. The larvae of mushroom mosquitoes live in the fruiting bodies of the cap mushrooms.

Flies as opposed to mosquitoes. have short antennae. Their larvae are white, as a rule, legless and headless. In the house fly, worm-like larvae live and develop in kitchen waste, in heaps of manure and sewage, where the fly lays its eggs. Before pupation, the larvae crawl out of the sewage, penetrate the soil and turn into pupae.

Adult flies hatched from pupae fly everywhere in search of poverty. From latrines and cesspools, they fly over to openly lying food and pollute it. Flies transfer bacteria of gastrointestinal diseases and ascaris eggs to human food. Therefore, it is very important to fight the flies. Food is protected from flies with gauze or caps, vegetables and fruits are washed before use.

Midges- long-wattled bloodsuckers of small size, the larvae of which develop at the bottom of reservoirs with running water. In the tropics and subtropics, in the Crimea, very small mosquitoes are found - mosquitoes... Their larvae develop in moist soils, rodent burrows, etc. Mosquitoes are carriers of many diseases (malaria, etc.). We have a "Hessian fly" that destroys cereal plants.

Gadflies, horseflies cause great harm to humans and pets with their bites, as well as the ability to tolerate pathogens of such dangerous diseases as tularemia, anthrax.

At the same time, flies are pollinators of many plants.

Rat flea can transmit the plague pathogens from sick rodents - a very dangerous disease that once claimed thousands of lives.