Insects. Who are they and how many are there? How many types of insects do we know? The fight against harmful insects

General characteristics of the class

The body of adult insects is divided into three sections: head, thorax and abdomen.

• Head, consisting of six merged segments, distinctly separated from the chest and movably connected to it. On the head there is a pair of jointed antennae or screeds, a mouth apparatus and two compound eyes; many also have one or three simple eyes.

  Two complex, or faceted, eyes are located on the sides of the head, in some species they are very strongly developed and can occupy most of the surface of the head (for example, in some dragonflies, horseflies). Each compound eye consists of several hundred to several thousand facets. Most insects are blind to red, but they see and are attracted to ultraviolet light. This feature of insect vision is the basis for the use of light traps, which emit most of the energy in the violet and ultraviolet regions, for collecting and studying the ecological characteristics of nocturnal insects (certain families of butterflies, beetles, etc.).

  The oral apparatus consists of three pairs of limbs: upper jaws, lower jaws, lower lip (the fused second pair of lower jaws) and the upper lip, which is not a limb, but is an outgrowth of chitin. The oral apparatus also includes a chitinous protrusion of the bottom of the oral cavity - the tongue or hypopharynx.

  

  

  

  Depending on the method of feeding, the oral organs of insects have a different structure. There are the following types of oral apparatus:

  • gnawing-chewing - elements of the oral apparatus look like short hard plates. Observed in insects that feed on solid plant and animal food (beetles, cockroaches, orthoptera)
  • piercing-sucking - elements of the oral apparatus have the form of elongated hair-like bristles. Observed in insects that feed on plant cell sap or animal blood (bugs, aphids, cicadas, mosquitoes, mosquitoes)
  • licking-sucking - elements of the oral apparatus have the form of tubular formations (in the form of a proboscis). It is noted in butterflies that feed on the nectar of flowers and fruit juice. In many flies, the proboscis is strongly transformed, at least five of its modifications are known, from a piercing-cutting organ in horseflies to a soft "licking" proboscis in flower flies that feed on nectar (or in carrion flies that feed on liquid parts of manure and carrion).

  Some species do not feed as adults.

  The structure of the antennae, or ties, of insects is very diverse - filiform, bristle-shaped, serrate, comb-shaped, club-shaped, lamellar, etc. Antennae one pair; they bear the organs of touch and smell, and are homologous to crustacean antennules.

  The sense organs on the antennae of insects tell them not only the state of the environment, they help them communicate with relatives, find a suitable habitat for themselves and their offspring, as well as food. Females of many insects attract males with the help of smells. Males of the lesser nocturnal peacock eye can smell a female at a distance of several kilometers. Ants recognize by the smell of females from their anthill. Some species of ants mark their way from the nest to the source of food thanks to odorous substances that are secreted from special glands. With the help of antennae, ants and termites smell the smell left by their relatives. If both antennae capture the smell to the same extent, then the insect is on the right track. Attractant substances that are released by female butterflies ready for mating are usually carried by the wind.

• Breast insects consists of three segments (prothorax, mesothorax and metathorax), to each of which a pair of legs is attached from the ventral side, hence the name of the class - six-legged. In addition, in higher insects, the chest bears two, less often one pair of wings.

  The number and structure of the limbs are characteristic features of the class. All insects have 6 legs, one pair on each of the 3 thoracic segments. The leg consists of 5 sections: coxa (plow), trochanter (trochanter), femur (femur), lower leg (tibia) and jointed tarsus (tarsus). Depending on the lifestyle, the limbs of insects can vary greatly. Most insects have walking and running legs. In grasshoppers, locusts, fleas and some other species, the third pair of legs is of a jumping type; in bears that make passages in the soil, the first pair of legs is digging legs. In aquatic insects, such as the swimming beetle, the hind legs are transformed into rowing, or swimming.

  Digestive system presented

  • The anterior intestine, starting from the oral cavity and subdividing into the pharynx and esophagus, the posterior section of which expands, forming a goiter and chewing stomach (not in all). In consumers of solid food, the stomach has thick muscular walls and carries chitinous teeth or plates from the inside, with the help of which food is crushed and pushed into the middle intestine.

    The salivary glands (up to three pairs) also belong to the foregut. The secret of the salivary glands performs a digestive function, contains enzymes, moistens food. In bloodsuckers, it contains a substance that prevents blood clotting. In bees, the secret of one pair of glands is mixed in the crop with flower nectar and forms honey. In worker bees, the salivary glands, the duct of which opens into the pharynx (pharyngeal), secrete special protein substances ("milk"), which are used to feed the larvae that turn into queens. In caterpillars of butterflies, larvae of caddisflies and hymenoptera, the salivary glands are transformed into silk-secreting or spinning glands, producing a silky thread for making a cocoon, protective formations, and other purposes.

  • The middle intestine on the border with the foregut is covered from the inside with glandular epithelium (pyloric outgrowths of the intestine), which secrete digestive enzymes (the liver and other glands are absent in insects). Absorption of nutrients occurs in the midgut.
  • The hindgut receives undigested food residues. Here, water is sucked out of them (this is especially important for desert and semi-desert species). The posterior intestine ends with an anus, which leads out excrement.

  

  excretory organs represented by malpighian vessels (from 2 to 200), which have the form of thin tubules that flow into the digestive system at the border between the middle and hindgut, and the fat body, which performs the function of "accumulation kidneys". The fat body is a loose tissue located between the internal organs of insects. Has a whitish, yellowish or greenish color. Fat body cells absorb metabolic products (salts of uric acid, etc.). Further, the excretion products enter the intestines and, together with the excrement, are excreted. In addition, the cells of the fat body accumulate reserve nutrients - fats, proteins and carbohydrate glycogen. These reserves are spent on the development of eggs during wintering.

  Respiratory system- trachea. This is a complex branching system of air tubes that directly deliver oxygen to all organs and tissues. On the sides of the abdomen and chest there are most often 10 pairs of spiracles (stigmas) - holes through which air enters the trachea. From the stigmas, large main trunks (tracheae) begin, which branch into smaller tubes. In the chest and anterior part of the abdomen, the trachea are expanded and form air sacs. Tracheae permeate the entire body of insects, braid tissues and organs, enter inside individual cells in the form of the smallest branches - tracheoles, through which gas exchange takes place. Carbon dioxide and water vapor are removed to the outside through the tracheal system. Thus, the tracheal system replaces the functions of the circulatory system in supplying tissues with oxygen. The role of the circulatory system is reduced to the delivery of digested food to the tissues and the transfer of decay products from the tissues to the excretory organs.

  Circulatory system in accordance with the characteristics of the respiratory organs, it is relatively poorly developed, not closed, consists of a heart and a short, unbranched aorta extending from the heart to the head. A colorless liquid containing white blood cells circulating in the circulatory system is called, in contrast to blood, hemolymph. It fills the body cavity and the spaces between organs. The heart is tubular, located on the dorsal side of the abdomen. The heart has several chambers capable of pulsating, each of which opens a pair of holes equipped with valves. Through these openings, blood (hemolymph) enters the heart. The pulsation of the chambers of the heart is caused by the contraction of special pterygoid muscles. Blood moves in the heart from the posterior end to the anterior, then enters the aorta and from it into the head cavity, then washes the tissues and pours through the cracks between them into the body cavity, into the spaces between the organs, from where it enters the heart through special openings (ostia). The blood of insects is colorless, or greenish-yellow (rarely red).

  Nervous system reaches an exceptionally high level of development. It consists of the supraoesophageal ganglion, circumoesophageal connectives, suboesophageal ganglion (it was formed as a result of the fusion of three ganglia) and the ventral nerve cord, which in primitive insects consists of three thoracic ganglia and eight abdominal ones. In higher groups of insects, neighboring nodes of the ventral nerve chain merge by combining three thoracic nodes into one large node or abdominal nodes into two or three or one large node (for example, in real flies or horn beetles).

  The supraesophageal ganglion, which is often called the brain, is especially complex. It consists of three sections - anterior, middle, posterior and has a very complex histological structure. The brain innervates the eyes and antennae. In its anterior section, the most important role is played by such a structure as mushroom bodies - the highest associative and coordinating center of the nervous system. The behavior of insects can be very complex, has a pronounced reflex character, which is also associated with a significant development of the brain. The subpharyngeal node innervates the oral organs and the anterior intestine. The thoracic ganglia innervate the organs of movement - the legs and wings.

  Insects are characterized by very complex forms of behavior, which are based on instincts. Particularly complex instincts are characteristic of the so-called social insects - bees, ants, termites.

  sense organs reach an exceptionally high level of development, which corresponds to a high level of general organization of insects. Representatives of this class have organs of touch, smell, sight, taste and hearing.

  All sense organs are based on the same element - the sensilla, consisting of one cell or a group of sensitive receptor cells with two processes. The central process goes to the central nervous system, and the peripheral process goes to the outer part, represented by various cuticular formations. The structure of the cuticular sheath depends on the type of sensory organs.

  The organs of touch are represented by sensitive hairs scattered throughout the body. The organs of smell are located on the antennae and mandibular palps.

  The organs of vision play a leading role for orientation in the external environment, along with the organs of smell. Insects have simple and compound (faceted) eyes. Compound eyes are made up of a huge number of individual prisms, or ommatidia, separated by an opaque layer. This structure of the eyes gives "mosaic" vision. Higher insects have color vision (bees, butterflies, ants), but it differs from human vision. Insects perceive mainly the short-wavelength part of the spectrum: green-yellow, blue and ultraviolet rays.

  Reproductive organs are in the abdomen. Insects are dioecious organisms, they have well-defined sexual dimorphism. Females have a pair of tubular ovaries, oviducts, accessory sex glands, a seminal receptacle, and often an ovipositor. Males have a pair of testes, vas deferens, ejaculatory canal, accessory sex glands and copulatory apparatus. Insects reproduce sexually, most of them lay eggs, there are also viviparous species, their females give birth to live larvae (some aphids, botflies, etc.).

  After a certain period of embryonic development, larvae emerge from the laid eggs. Further development of larvae in insects of various orders may occur with incomplete or complete metamorphosis (Table 16).

  Life cycle. Insects are dioecious animals with internal fertilization. According to the type of postembryonic development, insects are distinguished with incomplete (in highly organized) and complete (in higher) metamorphosis (transformation). Complete metamorphosis includes egg, larva, pupa and adult stages.

  In insects with incomplete transformation, a young individual emerges from the egg, which is similar in structure to an adult insect, but differs from it in the absence of wings and underdevelopment of the genital organs - the nymph. Often they are called larvae, which is not entirely accurate. Its habitat conditions are similar to adult forms. After several molts, the insect reaches its maximum size and turns into an adult form - an imago.

  In insects with complete transformation, larvae emerge from eggs, which differ sharply in structure (have a worm-like body) and in habitat from adult forms; thus, the mosquito larva lives in water, while the imaginal forms live in the air. The larvae grow, go through a series of stages, separated from each other by molts. At the last molt, an immobile stage is formed - the pupa. The pupae do not feed. At this time, metamorphosis occurs, the larval organs undergo decay, and adult organs develop in their place. Upon completion of metamorphosis, a sexually mature winged individual emerges from the pupa.

  Tab 16. Development of insects	Type of development
  	Superorder I. Insects with incomplete metamorphosis	Superorder 2. Insects with complete metamorphosis
  Number of stages	3 (egg, larva, adult)	4 (egg, larva, pupa, adult)
  Larva	Similar to an adult insect in external structure, lifestyle and nutrition; smaller, wings absent or incompletely developed	Differs from an adult insect in external structure, lifestyle and nutrition
  chrysalis	Missing	Available (histolysis of larval and histogenesis of adult tissues and organs occurs in the immobile pupa)
  Detachment	Order Orthoptera (Orthoptera)	Squad of hard-winged, or beetles (Coleoptera) Order Lepidoptera, or butterflies (Lepidoptera) Order Hymenoptera (Hymenoptera)

  Class Overview

  The class of insects is divided into more than 30 orders. The characteristics of the main units are given in table. 17.

  Beneficial insects

  Honey bee or domestic bee [show] A family usually lives in a hive, which consists of 40-70 thousand bees, of which one is a queen, several hundred male drones, and all the rest are worker bees. The uterus is larger than the rest of the bees, it has well-developed reproductive organs and the ovipositor. Every day, the uterus lays from 300 to 1000 eggs (on average, this is 1.0-1.5 million in a lifetime). Drones are slightly larger and thicker than worker bees, they do not have wax glands and the queen. Drones develop from unfertilized eggs. Worker bees are underdeveloped females unable to reproduce; their ovipositor has turned into an organ of defense and attack - a sting. The sting consists of three sharp needles, between them there is a channel for removing the poison formed in a special gland. In connection with feeding on nectar, the gnawing mouth organs have changed significantly; when eating, they form a kind of tube - a proboscis, through which nectar is absorbed with the help of the muscles of the pharynx. The upper jaws are also used for building honeycombs and other construction work. Nectar is collected in an enlarged goiter and turns into honey there, which the bee regurgitates into the cells of the honeycomb. There are numerous hairs on the head and chest of the bee, when the insect flies from flower to flower, pollen sticks to the hairs. The bee cleans pollen from the body, and it accumulates in the form of a lump, or pollen, in special recesses - baskets on the hind legs. The bees drop pollen into the cells of the honeycomb and fill it with honey. Perga is formed, with which the bees feed the larvae. On the last four segments of the bee's abdomen are wax glands, which outwardly look like light spots - mirrors. Wax comes out through the pores and solidifies in the form of thin triangular plates. The bee chews these plates with its jaws and builds honeycomb cells from them. The wax glands of the worker bee begin to secrete wax on the 3rd-5th day of its life, reach their maximum development on the 12th-28th day, then decrease and regenerate. In the spring, worker bees begin to collect pollen and nectar, and the queen lays one fertilized egg in each cell of the honeycomb. Three days later, the eggs hatch into larvae. Worker bees feed them for 5 days with "milk" - a substance rich in proteins and lipids, which is secreted by the maxillary glands, and then with bee bread. A week later, inside the cell, the larva weaves a cocoon and pupates. After 11-12 days, a young worker bee flies out of the pupa. For several days, she performs various work inside the hive - she cleans the cells, feeds the larvae, builds combs, and then begins to fly out for a bribe (nectar and pollen). In slightly larger cells, the uterus lays unfertilized eggs, from which drones develop. Their development lasts several days longer than the development of worker bees. The uterus lays fertilized eggs in large cells-queuing cells. From them larvae hatch, which bees feed all the time with "milk". These larvae develop into young queens. Before the young queen emerges, the old one tries to destroy the mother liquor, but the worker bees prevent her from doing so. Then the old queen with a part of the worker bees flies out of the hive - swarming occurs. A swarm of bees is usually transferred to a free hive. The young queen flies out of the hive along with the drones, and after fertilization returns. The bees have a well-developed supra-pharyngeal ganglion, or brain, it is distinguished by a strong development of mushroom-shaped, or stalked, bodies, with which the complex behavior of bees is associated. Having found flowers rich in nectar, the bee returns to the hive and begins to describe figures resembling the number 8 on the combs; her abdomen oscillates. This kind of dance signals to other bees in which direction and at what distance the bribe is located. The complex reflexes and instincts that determine the behavior of bees are the result of a long historical development; they are inherited. People have been breeding bees in apiaries since ancient times. The collapsible frame hive was an outstanding achievement in the development of beekeeping; it was invented by the Ukrainian beekeeper P.I. Prokopovich in 1814. The useful activity of bees lies primarily in the cross-pollination of many plants. With bee pollination, the yield of buckwheat increases by 35-40%, sunflower - by 40-45%, cucumbers in greenhouses - by more than 50%. Bee honey is a valuable food product; it is also used for therapeutic purposes in diseases of the gastrointestinal tract, heart, liver, and kidneys. Royal jelly and bee glue (propolis) are used as medicinal preparations. In medicine, bee (wasp) venom is also used. Beeswax is widely used in various industries - electrical engineering, metallurgy, chemical production. The annual world harvest of honey is about 500 thousand tons. [show] The silkworm has been known to people for over 4 thousand years. In nature, it can no longer exist, it is bred in artificial conditions. Butterflies don't eat. Sedentary whitish female silkworms lay 400-700 eggs (the so-called grena). Caterpillars are brought out of them in special rooms on racks, which are fed with mulberry leaves. The caterpillar develops within 26-40 days; during this time she sheds four times. An adult caterpillar weaves a cocoon of silk thread, which is produced in its silk gland. One caterpillar secretes a thread up to 1000 m long. The caterpillar winds this thread around itself in the form of a cocoon, inside which it pupates. A small part of the cocoons is left alive - later butterflies hatch from them, which lay eggs. Most cocoons are killed by hot steam or exposure to an ultra-high frequency electromagnetic field (at the same time, the pupae inside the cocoons heat up to 80-90 ° C in a few seconds). Then the cocoons are unwound on special machines. More than 90 g of raw silk is obtained from 1 kg of cocoons.

  If it were possible to accurately calculate the harm and benefits of insects for the national economy, then perhaps the benefits would significantly exceed the losses. Insects provide cross-pollination of about 150 species of cultivated plants - garden, buckwheat, cruciferous, sunflower, clover, etc. Without insects, they would not produce seeds and would die themselves. The aroma and color of higher flowering plants have evolved as special signals to attract bees and other pollinating insects. The sanitary importance of such insects as gravedigger beetles, dung beetles, and some others is great. Dung beetles were specially brought to Australia from Africa, because without them a large amount of manure accumulated on the pastures, which prevented the growth of grass.

  Insects play a significant role in soil formation processes. Soil animals (insects, centipedes, etc.) destroy fallen leaves and other plant residues, assimilating only 5-10% of their mass. However, soil microorganisms decompose the excrement of these animals faster than mechanically crushed leaves. Soil insects, along with earthworms and other soil inhabitants, play a very important role in its mixing. Lacquer insects from India and South-East Asia secrete a valuable technical product - shellac, other species of insects - valuable natural paint carmine.

  Harmful insects

  Many species of insects damage agricultural and forest crops; up to 3,000 pest species have been registered in Ukraine alone.

  [show] Adult beetles eat young leaves of trees in spring (they eat leaves of oak, beech, maple, elm, hazel, poplar, willow, walnut, fruit trees). The females lay their eggs in the soil. The larvae feed on thin roots and humus until autumn, winter deep in the soil, and the next spring they continue to eat roots (mainly herbaceous plants). After the second wintering in the soil, the larvae begin to feed on the roots of trees and shrubs; young stands with an underdeveloped root system may die due to damage. After the third (or fourth) wintering, the larvae pupate. Depending on the geographic latitude of the area and climatic conditions, the development of the May beetle lasts from three to five years. [show] The Colorado potato beetle began to damage potatoes in 1865 in North America in the state of Colorado (hence the name of the pest). After the First World War, it was brought to Europe and quickly spread east to the Volga and the North Caucasus. Females lay eggs on potato leaves, 12-80 eggs per clutch. Larvae and beetles feed on leaves. For a month, a beetle can eat 4 g, a larva - 1 g of leaves. If we take into account that on average a female lays 700 eggs, then the second generation of one female can destroy 1 ton of potato leaves. The larvae pupate in the soil, and adult beetles overwinter there. In Europe, unlike North America, there are no natural enemies of the Colorado potato beetle that would restrain its reproduction. Common beet weevil [show] Adult beetles eat sugar beet seedlings in spring, sometimes completely destroying crops. The female lays her eggs in the soil, the larvae feed on the roots and root crops of sugar beets. At the end of summer, the larvae pupate in the soil, while the young beetles hibernate. Bed bug harmful turtle [show] Bed bug harms wheat, rye and other cereals. Adult bugs hibernate under fallen leaves in forest belts and shrubs. From here in April-May they fly to winter crops. At first, the bugs feed by piercing the stems with their proboscis. Then the females lay 70-100 eggs on the leaves of cereals. The larvae feed on the cell sap of the stems and leaves, later they move on to the ovaries and ripening grain. After piercing the grain, the bug secretes saliva into it, which dissolves the proteins. Damage causes drying of the grain, a decrease in its germination and a deterioration in baking qualities. [show] The front wings are light brown, sometimes almost black. They show a typical "scoop pattern", represented by a kidney-shaped, round or wedge-shaped spot, edged with a black line. The hindwings are light grey. Antennae in males slightly combed, in females filiform. Wingspan 35-45 mm. Caterpillars are earthy gray in color with a dark head. The caterpillar of the Winter scoop in autumn damages (gnaws) mainly the seedlings of winter cereals (hence the name of the pest), to a lesser extent vegetables and root crops; in the southern regions harms sugar beets. Adult caterpillars overwinter by burrowing into the soil in fields sown with winter crops. In spring they quickly pupate. Butterflies emerging from pupae in May fly at night and at dusk. Females lay their eggs on millet and tilled crops - sugar beets, cabbage, onions, etc., and in places with sparse vegetation, so they are often attracted to plowed fields. The caterpillars destroy the sown grains, gnaw the seedlings of plants in the area of ​​the root neck, eat the leaves. Very voracious. If 10 caterpillars live on 1 m 2 of crops, then they destroy all plants and "bald spots" appear on the fields. At the end of July, they pupate, in August the second generation butterflies fly out of the pupae, which lay their eggs on weeds on stubble or winter seedlings. One female winter cutworm can lay up to 2000 eggs. In Ukraine, during the growing season, two generations of the winter cutworm develop. [show] One of our most common butterflies. The upper side of the wings is white, the outer corners are black. Males have no black spots on the front wings, females have 2 black round spots and 1 club-shaped spot on each wing. The hindwings of both males and females are the same - white, with the exception of a black wedge-shaped spot at the anterior margin. The underside of the hindwings is a characteristic yellowish-green coloration. Wingspan up to 60 mm. The body of the cabbage is covered with thick, very short hairs, giving it a velvety appearance. Variegated coloring of caterpillars is a warning about inedibility. Caterpillars are bluish-green, with yellow stripes and small black dots, the abdomen is yellow. In caterpillars of cabbage butterflies, the poisonous gland is located on the lower surface of the body, between the head and the first segment. Defending themselves, they burp a green slurry from their mouths, to which the secretions of a poisonous gland are mixed. These secretions are a caustic bright green liquid, which the caterpillars try to coat the attacking enemy with. For small birds, a dose of several individuals of these animals can be fatal. Swallowed cabbage caterpillars cause the death of domestic ducks. People who collected these insects with their bare hands happened to end up in the hospital. The skin on the hands was reddened, inflamed, the hands were swollen and itchy. Cabbage butterflies fly during the day in May-June and with a short break throughout the second half of summer and autumn. They feed on the nectar of flowers. Eggs are laid in clusters of 15-200 eggs on the underside of a cabbage leaf. In total, the butterfly lays up to 250 eggs. Young caterpillars live in groups, scrape off the pulp of cabbage leaves, older ones eat away the entire pulp of the leaf. If 5-6 caterpillars feed on a cabbage leaf, then they eat it whole, leaving only large veins. To pupate, caterpillars crawl onto surrounding objects - a tree trunk, a fence, etc. During the growing season, two or three generations of cabbage whites develop. Cabbage is common in the European part of the former USSR; this pest does not exist in Siberia, since butterflies cannot withstand severe winter frosts. The damage caused by cabbage is very great. Often, many hectares of cabbage are completely destroyed by this pest. Interesting flights of butterflies. With strong reproduction, butterflies gather in large masses and fly over considerable distances. [show] Willow borer - Cossus cossus (L.) Willow borer damages the bast and wood of poplars, willows, oaks, other deciduous trees and fruit species. Butterflies appear in nature from the end of June, mainly in July, and depending on the geographical location, in some places even before mid-August. They fly slowly in the late evening. Summer lasts a maximum of 14 days. During the day, they sit in a characteristic pose with a slanting chest on the lower part of the trunk. Females lay eggs in groups of 15-50 pieces in cracks in the bark, in damaged places, cancerous wounds of trunks at heights up to 2 m. Caterpillars hatch after 14 days. First, the bast tissues are eaten together. On older trees with thick bark in the lower part of the trunk, the caterpillars eat out separate long, irregularly passing, oval passages in the cross section only after the first wintering. The walls of the passages are destroyed by a special liquid and are brown or black. On thinner trunks with smooth bark, caterpillars penetrate the wood earlier, usually within a month after hatching. The chips and excrement of the caterpillar are pushed out through the bottom hole. At the end of the growing season, when the leaves fall, the feeding of the caterpillars stops, which hibernate in passages until the foliage blooms, i.e. until April - May, when the caterpillars continue to feed in separate passages again until autumn, hibernate once more and finish feeding. They pupate either at the end of a circular passage, where a flight hole is prepared in advance, closed with chips, or in the ground, near a damaged trunk in a cocoon of chips. The pupal stage lasts 3-6 weeks. Before flying, the pupa, with the help of spines, protrudes halfway out of the flight hole or out of the cocoon, so that the butterfly can more easily leave the exuvium. The generation is maximum two years. The willow borer is distributed throughout Europe, mainly in the middle and southern parts. It occurs throughout the forest zone of the European part of Russia, in the Caucasus, in Siberia, and also in the Far East. Known in western and northern China and Central Asia. The front wings of the moth are gray-brown to dark gray with a "marble" pattern and blurry gray-white spots, as well as dark transverse wavy lines. The hindwings are dark brown with matte dark wavy lines. The chest is dark above, whitish towards the abdomen. The dark abdomen has light rings. The male has a wingspan of 65-70 mm, the female - from 80 to 95 mm. The abdomen of the female is terminated by a retractable, well-marked ovipositor. The caterpillar immediately after hatching is cherry-red, later - meat-red. Head and occipital shield shiny black. An adult caterpillar is 8-11 cm (most often 8-9 cm), then it is yellowish meat-colored, brown on top with a purple tint. The yellow-brown occipital shield has two dark spots. The breathing hole is brown. The egg is oval-longitudinal, light brown with black stripes, dense, 1.2 mm in size. Many insects, especially those with piercing-sucking mouthparts, carry pathogens of various diseases. Malarial Plasmodium [show] Plasmodium malaria, the causative agent of malaria, enters the human bloodstream when bitten by a malarial mosquito. Back in the 30s of the XX century. in India, more than 100 million people fell ill with malaria every year; in the USSR in 1935, 9 million malaria cases were registered. In the last century, malaria was eradicated in the Soviet Union; in India, the incidence has dropped sharply. The center of incidence of malaria has moved to Africa. Theoretical and practical recommendations for the successful fight against malaria in the USSR and neighboring countries were developed by VN Beklemishev and his students. The nature of damage to plant tissues depends on the structure of the oral apparatus of the pest. Insects with gnawing mouthparts gnaw or eat away sections of the leaf blade, stem, root, fruit, or make passages in them. Insects with piercing-sucking mouthparts pierce the integumentary tissues of animals or plants and feed on blood or cell sap. They cause direct harm to a plant or animal, and also often carry pathogens of viral, bacterial and other diseases. Annual losses in agriculture from pests amount to about 25 billion rubles, in particular, the damage from harmful insects in our country annually averages 4.5 billion rubles, in the USA - about 4 billion dollars. Dangerous pests of cultivated plants in the conditions of Ukraine include about 300 species, in particular, beetles, larvae of click beetles, mole cricket, grain bugs, Colorado potato beetle, common beet weevil, turtle bugs, meadow and stem moths, winter and cabbage scoops , hawthorn, gypsy moth, ringed moth, apple codling moth, American white butterfly, beet root aphid, etc. The fight against harmful insects To combat harmful insects, a comprehensive system of measures has been developed - preventive, including agro- and forestry, mechanical, physical, chemical and biological. Preventive measures consist in observing certain sanitary and hygienic standards that prevent the mass reproduction of harmful insects. In particular, timely cleaning or destruction of waste, garbage helps to reduce the number of flies. Drainage of swamps leads to a decrease in the number of mosquitoes. Of great importance is also the observance of the rules of personal hygiene (washing hands before eating, thoroughly washing fruits, vegetables, etc.). Agrotechnical and forestry measures, in particular the destruction of weeds, proper crop rotations, proper soil preparation, the use of healthy and sedimentary material, pre-sowing seed cleaning, well-organized care of cultivated plants, create unfavorable conditions for the mass reproduction of pests. Mechanical measures consist in the direct destruction of harmful insects manually or with the help of special devices: flycatchers, adhesive tapes and belts, trapping grooves, etc. In winter, wintering nests of hawthorn and goldtail caterpillars are removed from trees in gardens and burned. Physical measures - the use of some physical factors for the destruction of insects. Many moths, beetles, Diptera fly towards the light. With the help of special devices - light traps - you can timely learn about the appearance of some pests and start fighting them. To disinfect citrus fruits infected with the Mediterranean fruit fly, they are subjected to cooling. Barn pests are destroyed using high frequency currents. Therefore, integrated pest management is of particular importance, which involves a combination of chemical, biological, agrotechnical and other methods of plant protection with the maximum use of agrotechnical and biological methods. In integrated methods of control, chemical treatments are carried out only in foci that threaten a sharp increase in the number of pests, and not continuous treatment of all areas. With the aim of protecting nature, it is envisaged that biological means of protecting plants will be widely used.

Class Insects- this is the most highly organized, numerous, diverse class of arthropods, common in all environments of life, in aquatic - secondarily. Most representatives are capable of flight. Insects belong to the phylum Arthropoda.

Meaning of insects:

1. Participation in the cycle of substances

2. Important role in food chains

3. Pollination of flowers and seed dispersal

4. Obtaining food, medicines, silk

5. Agricultural pests

6. Predatory insects exterminate agricultural pests

7. Damage to fabrics, wood, books, mechanisms