General characteristics of Lepidoptera. Lepidoptera - an order of insects with complete transformation Butterfly what type of animal

27. Order Hymenoptera

The honey bee, wild bees, bumblebees, ants, ichneumon wasps, sawflies, horntails are hymenopterans that have two pairs of membranous wings as adults (hence the name of their order). There are also wingless insects that are part of this order, for example worker ants. About 300,000 species of Hymenoptera are known.

Pattern: Hymenoptera - great horntail and birch sawfly

Sawflies: In sawflies, females have an ovipositor that resembles a saw. These insects use it to saw through plant tissue in order to lay eggs in the cuts made. Sawfly larvae are similar to butterfly caterpillars and are called false caterpillars. They are distinguished from caterpillars that have 2-5 pairs of prolegs by the presence of 6-8 pairs of prolegs. Sawfly larvae feed mainly on plant leaves. Some of them are known as harmful pests of trees and shrubs. Thus, larvae of pine sawflies often completely eat up tree needles.

Horntails: Horntails got their name because their females have a long ovipositor, hard as a horn. The female uses it, like a drill, to drill into wood and lays eggs in the holes made. Horntail larvae feed on wood, damaging many trees.

Riders

Pattern: riders - whitefish (left), rissa (right)

Stinging Hymenoptera

Pattern: Stinging Hymenoptera

Stinging Hymenoptera are the well-known wasps, bees, bumblebees and ants. They are called stinging because in females the ovipositor, retracted into the abdomen, has turned into a sting - a weapon of defense and attack. Ants have a very short sting, so they cannot sting. Among bees and wasps, species leading a solitary lifestyle predominate, when each female independently raises her offspring. For others (some bees and some wasps, all bumblebees and all ants), caring for offspring led to the emergence of a social way of life. U social insects in one nest all individuals of one or several generations are united, and different individuals perform different functions. By the way, insects from at least two successive generations live together - maternal and daughter. Most often, the Hymenoptera society is a single family consisting of the offspring of one female.

Picture: forest red ants and anthill

The main feature of the society of stinging hymenoptera is that it consists of such members, each of which cannot exist without the others. Such a society necessarily includes three groups: fertile females(or queens, the so-called queens), performing the functions of reproduction and settlement; males participating only in reproduction - drones; workers, which account for all the work involved in caring for females and males, as well as for the offspring. Workers build and protect nests and provide food to all family members. In social insects, workers are sterile females. In bees and wasps they are winged, in ants they are always wingless.

The role of stinging hymenoptera

The role of stinging hymenoptera is truly enormous. Bees and bumblebees are one of the main pollinators of flowering plants, and wasps and ants are our allies, destroying countless harmful insects to feed their offspring.

Morphologically Lepidoptera (butterflies) constitute a fairly compact group of winged insects. The entire body and 4 wings are densely covered with scales and partially with hairs. The head has large faceted eyes, well-developed labial palps and a long spirally twisted sucking proboscis located between them. The wings are usually wide, triangular, less often narrow or even lanceolate. The front and rear wings are fastened to each other with a special coupling device. The most common is the frenate type of wing coupling. In this case, traction is achieved using the frenulum (frenulum) and retinanulum (hitch). The frenulum is represented by one or several strong setae at the base of the hind wing, and the toe is either a row of setae or a curved outgrowth at the base of the fore wing. The venation of the wings of Lepidoptera is characterized by a significant (reduction of the transverse veins and slight branching of the main longitudinal trunks. The scales on the wings are differently colored and often form a rather complex pattern. Structural coloring (spots with a metallic sheen) is often observed. A fringe consisting of several rows of scales and hairs. In the thoracic region, the mesothorax is most developed. The prothorax on the sides of the tergite bears lobe-shaped appendages - patagia. In the mesothorax, similar formations are located above the base of the fore wings and are called tegulae. The oges are running, often with spurs on the legs. Some lepidopterans have fore legs strongly (reduced, hidden in the hair, and the butterflies move on four legs. The abdomen consists of 9 segments. The last segment is sharply modified, especially in males, in which it forms the copulatory apparatus. In females, the last segments of the abdomen (usually from the seventh to the ninth) converted into a telescopic soft ovipositor. In most cases, the reproductive system of female butterflies opens outwards with two genital openings. One of them, terminal, serves only for laying eggs, the second, located either at the end of the seventh segment or at the eighth segment, is a copulatory opening.

Family ermine moths (hyponomeutidae) - butterflies usually have a branched radius of the fore wings to form a radial cell. Moths, their caterpillars eat the leaves of an apple or bird cherry tree, respectively, entwining them with cobwebs. Cabbage and other cruciferous vegetables are seriously damaged by the cabbage moth (Plutella maculipennis).

Leaf roller family (Tortricidae)- differs from moth-like ones by wider elongated triangular fore wings, often with a transversely chopped off apex, the hind wings are elongated oval, without a long fringe.

Nymphalidae family Representatives of this family are distinguished by the underdeveloped front legs of butterflies; the pupa hangs head down.

Whitefish family (pieridae)– butterflies usually have white or yellow wings, the pupae are attached at the rear end of the body and are also girded with a silk thread. These include the pests cabbage grass (pieris brassicae) and turnip grass (pieris rapae).

Cocoon moth family (lasiocampidae) butterflies of medium size or large, with a thick, densely hairy body. The antennae of males are feathery, while those of females are comb-like. There are no proboscis. The wings are wide, usually without hooks. These include the ringed moth (malacosoma Neustria).

Noctuidae family– the proboscis is developed, the front wings usually have a characteristic scoop pattern, consisting of 5 thin wavy transverse stripes and 3 median spots. These include the fall armyworm (agrotis segetum), which severely damages the seedlings of winter crops in the fall.

Ursa family (arctiidae) characterized by a developed proboscis, the caterpillars are very hairy, hence the name of the family.

Volnyanka family (lymantriidae) are distinguished by an underdeveloped proboscis, feathery antennae of the male, caterpillars with tufts of hairs, the pupa is usually hairy, in a rare silky cocoon, on plants or among plant debris. This includes the gypsy moth (Lymantria dispar).

The most ethereal creatures on Earth - butterflies - amaze the imagination with their beauty and diversity. They especially fascinate people with their coloring. Many with their color palette resemble peacock tail or a motley fan. This living being is never disgusting. The graceful and light flight of a butterfly cannot be compared with anything! Spring, beauty and eternity are associated with her. A butterfly is a symbol of happiness, fidelity, love, immortality. In another way they are also called lepidoptera. Biologists distinguish the following closely related orders of insects: butterflies, Homoptera, Diptera, fleas. You will be interested to learn about the features of these wonderful insects.

Order of butterflies, or Lepidoptera

Lepidoptera are the largest group of insects from the phylum. A characteristic feature of all representatives of the order of butterflies is a scaly multi-colored cover of the body and wings. These scales are nothing more than modified hairs. They have different colors and can create complex and bizarre patterns. These patterns serve as camouflage, hiding the insect or signaling inedibility. For most species, patterns on the wings are of an identifying nature so that individuals of the same species can recognize each other.

Another identifying feature of the order of butterflies is the sucking mouthparts in the form of a long tubular proboscis. To eat, the butterfly extends its long proboscis, plunges it deep into the flower and sucks up the nectar.

The main source of food for the order of butterflies is the nectar of flowers, so they are considered the main pollinators of flowering plants. There is an opinion that with the advent of flowers on Earth, butterflies appeared.

Butterfly breeding

Everyone knows that butterflies are nocturnal and diurnal. go through the process of development. First, they lay eggs, from which larvae hatch, completely different from adults. These are caterpillars. By using salivary glands caterpillars secrete saliva and it is from this that the caterpillars weave a cocoon for the pupa. The caterpillar will turn into it after several molts. After some time, an adult butterfly (imago) flies out of the pupa. The most long duration The life of an imago is several months.

Nutritional Features

The annual development cycle of a butterfly varies depending on the species. Most often, butterflies produce one generation per year. There are species that produce two or three generations per year.

Individuality of the structure

Lepidoptera can have sizes from 2 mm to 15 cm. The smallest butterfly is considered to be the baby moth, which lives in the Canary Islands. The largest species is the Maak's swallowtail, which is common in Europe.

Like other insects, butterflies have an abdomen, head and thorax. It is a durable chitinous cover. Butterflies have two pairs of wings with modified scale hairs. It is with the help of these scales that the wings acquire their pattern and color. Butterflies can fly long distances. These insects come in two sexes.

Insect orders: butterflies, Homoptera, Diptera, fleas

Today there are about 150,000 species of squamates that live on all continents except Antarctica. Tropical areas are especially rich in brightly colored butterflies. In addition to butterflies, there are several other similar orders of insects: Homoptera, Diptera, fleas. We invite you to get acquainted with the main representatives of each squad:

Lepidoptera are of great importance in nature and human life. After all, butterflies are excellent pollinators of plants. Many large butterflies, such as swallowtail and Apollo, simply fascinate with their beauty. They become exhibits of many entomological collections.

Currently, the insect class is the most numerous in terms of the number of species. In addition, this is the most prosperous group of animals on Earth in terms of the breadth of spatial distribution and ecological differentiation. Insects have a number of common characteristics in internal structure, however, their appearance, development, lifestyle and other parameters vary greatly.

The division of the insect class into large systematic categories - subclasses, infraclasses, orders - is based on such important features as the structure of the wings, mouthparts, and type of postembryonic development. Additionally, other diagnostic signs are used.

Different authors give different taxonomies to the class, but the number of orders, regardless of the source, is quite impressive. The most famous of them are the order of Dragonflies (Odonata), Cockroaches (Blattodea), Termites (Isoptera), Orthoptera (Orthoptera), Homoptera (Homoptera), Hemiptera (Hemiptera), Coleoptera (Coleoptera), Hymenoptera (Hymenoptera), Diptera (Diptera) and , of course, Lepidoptera.

General characteristics of Lepidoptera

Butterflies are one of the most beautiful insects; the order Lepidoptera includes more than 140 (according to some sources 150) thousand species. However, among other insects this is a rather “young” group, the greatest development of which coincides with the flowering of flowering plants in Cretaceous period. The lifespan of an imago lasts from several hours, days, to several months. The difference in size in Lepidoptera is greater than in any other order. Their wingspan varies from 30 cm in the South American cutworm to half a centimeter in Eriocrania. Butterflies are most widespread in tropical latitudes. And in South America The Far East and Australia are home to the largest, brightly colored and seemingly interesting butterflies.

Thus, the record holders for the brightest color are representatives of the South American genus Morho and the Australian swallowtail Ulysses. Large (up to 15 - 18 cm), sparkling blue metal morphos are perhaps the dream of any collector. And in terms of migration, the best studied butterfly is the monarch butterfly, which lives in North and Central America and annually makes flights from Canada and the northern regions of the United States to the south.

The structure of an adult insect

An adult insect, or otherwise an imago, has the following structure. The body of a butterfly consists of three main sections: head, chest and abdomen. The segments of the head are fused into a common mass, while the segments of the thorax and abdomen are more or less clearly distinguishable. The head consists of an acron and 4 segments, a thorax of 3, and the abdomen in its entirety contains 11 segments and a telson. The head and chest bear limbs, the abdomen sometimes retains only their rudiments.

Head. The head is inactive, free, round in shape. Here there are highly developed convex compound eyes, occupying a significant part of the surface of the head, usually round or oval, surrounded by hairs. In addition to the compound eyes, there are sometimes two simple ocelli on the crown behind the antennae. A study of the ability of butterflies to see colors showed that their sensitivity to the visible parts of the spectrum varies depending on their lifestyle. Most perceive rays in the range of 6500-350 A. Butterflies react especially actively to ultraviolet rays. Butterflies are perhaps the only animals that perceive the color red. However, due to the absence of purely red flowers in the Central European flora, red is not perceived by hawk moths. Caterpillars of the pine silkworm, cabbage whiteweed and willow moth clearly distinguish different parts of the spectrum, reacting to violet rays as White color, red is perceived as darkness.

Fig.1. Head of the turnip, or white turnip (lat. Pieris rapae)

1 - Side view with a wrapped proboscis: B - labial palp, C - antenna; G - curled proboscis; 2 — front view with a folded proboscis: A — compound eye, B — labial palp; B - antennae; G - curled proboscis; 3 — side view with the proboscis deployed: B — labial palp; B - antennae; G - expanded proboscis

In different groups of butterflies, the antennae, or antennae, come in a wide variety of shapes: filiform, bristle-shaped, club-shaped, fusiform, feathery. Males usually have more developed antennae than females. The eyes and antennae with the olfactory sensilla located on them are the most important sensory organs of the butterfly.

Oral apparatus. The oral apparatus of Lepidoptera arose through the specialization of ordinary arthropod limbs. Absorption and grinding of food. The mouthparts of butterflies are no less a characteristic feature than the structure of the wings and the scales covering them.

In the vast majority of cases, they are represented by a soft proboscis that can curl up like a clock spring. The basis of this oral apparatus is made up of highly elongated internal lobes of the lower jaws, which form the valves of the proboscis. The upper jaws are absent or represented by small tubercles; The lower lip has also undergone a strong reduction, although its palps are well developed and consist of 3 segments. The butterfly's proboscis is very elastic and mobile; it is perfectly adapted to feeding on liquid food, which in most cases is flower nectar. The length of the proboscis of a particular species usually corresponds to the depth of nectar in the flowers that butterflies visit. In some cases, the source of liquid food for lepidopterans can be the flowing sap of trees, liquid excrement of aphids and other sugary substances. In some butterflies that do not feed, the proboscis may be underdeveloped or completely absent (thin moths, some moths).

Breast. The thorax consists of three segments called prothorax, mesothorax and metathorax. The thorax segments bear three pairs of motor limbs, inserted between the sternite and the lateral plate of each side. The limbs consist of one row of segments, in which we distinguish from the base to the end of the leg: the coxa, or thigh, a wide main segment; trochanter; thigh, the thickest segment of the leg; tibia, usually the longest of the segments; foot, consisting of different numbers very small segments. The last of which ends in one or two claws. There are numerous hairs or bristles on the chest, sometimes a tuft forms in the middle of the back; the abdomen is never connected to the chest by a stalk; in females it is generally thicker and equipped with a long ovipositor; males often have a crest at the end of the abdomen instead.

Wings. A characteristic feature of insects as a large systematic group is their ability to fly. Flight is accomplished with the help of wings; in most cases there are two pairs of them and they are located on the 2nd (mesothorax) and 3rd (methothorax) thoracic segments. The wings are essentially powerful folds of the body wall. Although the fully formed wing has the appearance of a thin solid plate, it is nevertheless two-layered; the upper and lower layers are separated by a thin gap, which is a continuation of the body cavity. The wings are formed in the form of bag-like protrusions of skin, into which the body cavity and trachea continue. The protrusions are flattened dorsoventrally; the hemolymph from them flows into the body, the upper and lower leaves of the plate come closer together, the soft tissues partially degenerate, and the wing takes on the appearance of a thin membrane.

Fig.2. Butterfly Greta (lat. Greta)

The beauty of a butterfly lies in its wings and the variety of their colors. Color range provide scales (hence the name of the order Lepidoptera). Scales – amazing inventions nature, which have faithfully served butterflies for millions of years, and now, when people have begun to study the properties of these amazing structures, they can also serve us. The scales on the wings are modified hairs. They have different shapes. For example, along the edge of the wing of the Apollo butterfly (Parnassius apollo) there are very narrow scales, almost indistinguishable from hairs. Closer to the middle of the wing, the scales widen, but remain sharp at the ends. And finally, very close to the base of the wing there are wide scales, similar to a hollow sac, attached to the wing by a tiny leg. The scales are arranged in regular rows across the wing: their ends are turned outward and cover the bases of the next rows.

Experiments have shown that the scaly cover of butterflies has a number of absolutely amazing properties, for example, good thermal insulation properties, which are most pronounced at the base of the wing. The presence of scaly cover increases the difference between the temperature of the insect and the ambient temperature by 1.5 - 2 times. In addition, wing scales are involved in creating lift. After all, if you hold a butterfly in your hands and some of its bright scales remain on your fingers, then the insect will have great difficulty flitting from place to place.

In addition, as experiments have shown, the scales dampen sound vibrations and reduce body vibration during flapping flight. In addition, during flight, a charge of static electricity appears on the wing of an insect, and the scales help this charge “drain” into external environment. A detailed study of the aerodynamic properties of butterfly scales led scientists to propose creating a coating for helicopters, designed in the image and likeness of the scaly cover of butterfly wings. Such a coating will improve the maneuverability of rotorcraft. Moreover, such a cover can be useful for parachutes, sails of yachts and even sports suits.

The remarkable coloring of butterflies also depends on their scaly clothing. The wing membranes themselves are colorless and transparent, and the scales contain pigment grains, which determine the wonderful coloring. Pigments selectively reflect light of a certain wavelength and absorb the rest. In nature, in general, all colors are formed mainly in this way. However, pigments can only reflect 60-70% of incoming light, and therefore the colors produced by the pigment are never as bright as they could theoretically be. Therefore, species for which particularly bright coloring is vitally important “look” for an opportunity to enhance it. Many species of butterflies, in addition to the usual pigment scales, have special scales called optical scales. They allow insects to become the owners of truly sparkling clothes.

Thin-layer interference occurs in optical flakes, the optical effect of which can be observed on the surface of soap bubbles. The lower part of the optical scales is pigmented; the pigment does not transmit light and thereby gives greater brightness to the interference color. Rays of light, passing through the transparent scales on the wing, are reflected from both their external and internal surfaces. As a result, the two reflections seem to overlap and reinforce each other. Depending on the thickness of the scales and the refractive index, light of a certain wavelength is reflected (all other rays are absorbed by the pigment). Butterflies “build” thousands of tiny thin-layer mirror-scales on the outer surface of their wings, and each such tiny mirror reflects light of a certain wavelength. The result is an absolutely stunning reflection effect of extraordinary brightness.

Fig.3. Willow Butterfly (Apatura iris)

The record holders for the brightest color are representatives of the South American genus Morho, but in middle lane Russia is home to butterflies with wonderful colors. Interference coloring is best seen in moths (genus Apatura and Limenitis). From a distance, these butterflies appear almost black, but up close they have a pronounced metallic sheen - from bright blue to purple.

It has recently become known that a similar interference effect can be created using various microstructures with unique optical properties. Moreover, the microstructures on the wings differ not only among representatives of different families with similar colors, but also among closely related species. Optical physicists from Exter University are now closely studying the intricacies of these effects using modern technology. At the same time, physicists make unexpected discoveries that turn out to be interesting not only for them, but also for biologists studying evolutionary processes.

The biological significance of the bright, variegated colors of the upper side of the wings, so often observed in club-whiskered butterflies, especially in nymphalids, is interesting. Their main significance is to recognize individuals of their own species at a great distance. Observations show that males and females of such variegated forms are attracted to each other from a distance by their color, and at close range final recognition occurs by the smell emitted by androconia.

If the upper side of the wings of nymphalids is always brightly colored, then a different type of coloring is characteristic of their lower side: they are usually cryptic, i.e. Protective. In this regard, two types of wing folding are interesting, widespread in nymphalids, as well as in other families day butterflies. In the first case, the butterfly, being in a resting position, pushes the front wings forward so that their lower surface, which has a protective coloring, is open almost throughout. The wings fold according to this type, for example, in the C-white wingwing (Polygonia C-album). Its upper side is brownish-yellow with dark spots and an outer border; the underside is gray-brown with a white “C” on the hind wings, which is how it gets its name. A motionless butterfly is also inconspicuous due to the irregular angular contour of its wings.

Fig.4. Kallima inachus butterfly with folded wings

Other species, such as the admiral and thistle, hide their fore wings between their hind wings so that only their tips are visible. In this case, two types of colors are expressed on the lower surface of the wings: that part of the front wings, which is hidden at rest, is brightly colored, the rest of the lower surface of the wings is clearly cryptic in nature.

In some cases, daytime butterflies have brightly colored upper and lower sides of their wings. This coloration is usually combined with the inedibility of the organism possessing it, which is why it is called warning coloring. Based on this feature, butterflies have the ability to mimicry. Mimicry refers to the similarity in color, shape and behavior between two or more species of insects. In butterflies, mimicry is expressed in the fact that some of the mimicking species turn out to be inedible, while others are deprived protective properties and only “imitate” their protected models. Such imitators are white butterflies (Dismorphia astynome) and perhybris butterflies (Perrhybris pyrrha).

Life cycle of lepidoptera, migratory behavior, role in biocenoses
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animal kingdom
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Features of lizards

Lepidoptera (or butterflies) are a fairly numerous order of insects. It includes about 150 thousand species. Representatives of Lepidoptera are various butterflies, moths and moths. Their main habitats are forests, meadows, as well as fields and gardens.

Butterflies are characterized by two pairs of large wings, usually brightly colored. The wings are covered with small chitinous multi-colored or colorless scales, arranged like tiles. Hence the name of the order - Lepidoptera. Scales are modified hairs; they are also found on the body.

Typically, butterflies that lead a diurnal lifestyle (limongrass, cabbage grass, etc.) have wings folded together above the body in a calm state. In nocturnal Lepidoptera they are arranged in a roof-like manner (for example, in moths).

The bright color of the wings serves butterflies to recognize representatives of their species, and also often has a protective function against predators. Thus, in some lepidopterans, the folded wings look like a leaf, i.e., the insect camouflages itself with its environment.

Life cycle of butterflies (metamorphoses): butterfly development

Other Lepidoptera have spots on their wings that, from a distance, resemble the eyes of birds. Such butterflies have a warning coloration. Usually moths have a protective coloring, and they find each other by smell.

Lepidoptera are insects with complete metamorphosis. The eggs hatch into caterpillar larvae, which subsequently pupate, after which a butterfly emerges from the pupa (the adult is the sexually mature stage). Caterpillars usually live longer than adults. There are species in which the larva lives for several years, while the butterfly itself lives for about a month.

Caterpillars feed mainly on leaves and have a gnawing type mouthparts. Butterflies have a sucking-type oral apparatus, represented by a proboscis coiled into a spiral tube, which is formed from the lower jaws and lower lip. Adult Lepidoptera most often feed on the nectar of flowers and at the same time pollinate plants. Their long proboscis unwinds, and they can use it to penetrate deep into the flower.

Lepidopteran caterpillars, in addition to three pairs of jointed legs, have pseudopods, which are outgrowths of the body with suckers or hooks. With their help, the larva is held on leaves and branches, and also crawls. The real legs are most often used to hold food.

Caterpillars have silk-secreting glands in their mouths that secrete a secretion that, when exposed to air, turns into a thin thread from which the larvae weave cocoons during pupation. In some representatives (for example, the silkworm), the thread has value. People get their silk. Therefore, the silkworm is bred as a pet. Also, silk thread, but coarser, is obtained from the oak silkworm.

There are many lepidopteran pests of forests, agricultural fields and gardens. Thus, if the oak budworm and Siberian silkworm multiply heavily, hectares of forests can be destroyed. Cabbage white caterpillars feed on cabbage leaves and other cruciferous plants.

Butterfly structure

Butterflies are arthropods - the most highly developed animals among invertebrates. They got their name from the presence of articulated tubular limbs.

Types of butterflies: appearance, varieties, insect structure

Another characteristic feature is the exoskeleton, formed by plates of a durable polysaccharide - quinine. In arthropods, due to the development of a durable outer shell and articulated limbs, a complex system of muscles appeared, attached from the inside to the integument. All movements of their body parts and internal organs are associated with muscles.

1- abdomen
2- breast
3- head with antennae
4- proboscis
5, 8, 9 - front, middle and hind legs
6, 7 - first and second pair of wings

Body of butterflies consists of three sections: head, chest and abdomen. With a webbed, short and soft neck, the head is attached to the chest, which consists of three segments motionlessly connected to each other. The connection points are not noticeable. Each of the segments bears a pair of jointed legs. Butterflies have three pairs of legs on their chest. The forelegs of male nymphalids and satyr pigeons are underdeveloped; in females they are more developed, but when walking they are also not used and are always pressed to the chest. In swallowtails and fatheads, all legs are normally developed, and the tibiae of their front legs are equipped with lobe-like structures, which are believed to be used for cleaning the eyes and antennae. In butterflies, the legs serve mainly for anchoring certain place and only then - for movement. Some butterflies have taste buds on their legs: before such a butterfly touches the sweet solution with its limb, it does not open its proboscis and does not start eating.

The head contains mouthparts, antennae and eyes. The oral apparatus of the sucking type is a non-segmented, spirally curled, long tubular proboscis at rest. The lower jaw and lower lip take part in its formation. Butterflies have no upper jaws. While eating, the butterfly straightens its long proboscis, plunging it deep into the flower, and sucks out the nectar. Adult lepidoptera use nectar as the main source of food, and therefore are among the main pollinators of flowering plants. All insects, including butterflies, have a special organ called the Jones organ, designed to analyze shaking and sound vibrations. With the help of this organ, insects not only assess the state of the physical environment, but also communicate with each other.

Internal structure

Butterflies have perfect nervous system and sensory organs, thanks to which they are perfectly oriented in environment, quickly respond to danger signals. Nervous system, like all arthropods, consists of a peripharyngeal ring and a ventral nerve cord. In the head, as a result of the fusion of clusters of nerve cells, the brain is formed. This system controls all movements of the butterfly, except for such involuntary functions as blood circulation, digestion, and breathing. Researchers believe that these functions are controlled by the sympathetic nervous system.

1- excretory organs
2- middle intestine
3- goiter
4- heart
5- anterior intestine
6- large intestine
7- genitals
8th nerve ganglion
9- brain

Circulatory system, like all arthropods, not closed. Blood directly washes internal organs and tissues while in the body cavity, transmitting to them nutrients and carrying harmful waste products to the excretory organs. It does not participate in the transfer of oxygen and carbon dioxide, that is, in respiration. Its movement is ensured by the work of the heart - a longitudinal muscular tube located in the dorsal part above the intestines. The heart, pulsating rhythmically, drives blood to the head end of the body. The backflow of blood is prevented by the heart valves. When the heart expands, blood enters it from the back of the body through its side openings, which are equipped with valves that prevent blood from flowing back. In the body cavity, unlike the heart, blood flows from the front end to the back, and then, entering the heart as a result of its pulsation, it is again directed to the head.

Respiratory system is a dense network of branched internal tubes - tracheas, through which air, entering through the external spiracles, is delivered directly to all internal organs and fabrics.

Excretory system- this is a bundle of thin tubes, the so-called Malpighian vessels, located in the body cavity. They are closed at the tops, and open at the bases into the intestines. Metabolic products are filtered out by the entire surface of the Malpighian vessels, and then inside the vessels they turn into crystals. Then they enter the intestinal cavity and, together with undigested food debris, are excreted from the body. Some harmful substances, especially poisons, accumulate and are isolated in the fat body.

Reproductive system females consist of two ovaries in which the formation of eggs occurs. The ovaries, passing into tubular oviducts, merge at their bases into a single unpaired oviduct, through which mature eggs are released. In the female reproductive system there is a spermatheca - a reservoir into which male sperm enter. Mature eggs can be fertilized by these sperm. The reproductive organs of the male are two testes that pass into the vas deferens, which unite into an unpaired ejaculatory duct, which serves to excrete sperm.

In this lesson you will learn about the most numerous groups insects that have mastered all possible habitats on our planet - beetles, or Coleoptera, butterflies or Lepidoptera, as well as flies and mosquitoes that belong to the order Diptera. In this lesson you will learn why beetles and flies buzz, mosquitoes ring, and butterflies fly silently. Get acquainted with the structural features of the body and oral apparatus of these insects, learn about the history of the interaction of these animals with humans. In this lesson we will talk about the Great Silk Road, malaria, naiads and nymphs, as well as why and how to protect yourself from beetles. From additional material you will learn about lacewings and caddisflies, and how their larvae live, feed and molt.

The topic of this lesson: “Three large orders of insects with complete transformation.” The purpose of the lesson is to outline the main differences between complete and incomplete (Fig. 1) transformation, as well as to talk about three orders of insects with complete transformation.

Rice. 1. Insect with incomplete metamorphosis

First, let's find out how this most complete transformation differs from an incomplete one. IN life cycle insects with incomplete transformation have only three stages: egg, larva and adult (Fig. 2).

Rice. 2. Incomplete transformation (bug)

Insect larvae with incomplete metamorphosis are similar in appearance to adults. They have compound eyes, mouthparts the same as those of the imago, and external wing rudiments (Fig. 3, 4).

Rice. 3. Bedbug larva

Rice. 4. Cockroach larva

There are four stages in the life cycle of insects with complete metamorphosis. These are egg, larva, pupa and imago. Insect larvae with complete metamorphosis bear little resemblance to adult individuals (Fig. 5).

Rice. 5. Complete transformation (diptera)

Indeed, it is difficult to recognize a butterfly in a worm-like larva of a beetle or a butterfly (Fig. 6).

Rice. 6. Caterpillar

The larva usually lacks compound eyes and always lacks external wing rudiments. It often has a different type of mouthparts than adults. Many organs of such larvae are temporary; they are absent in adult insects. These are, for example, abdominal prolegs, larval mouthparts and arachnoid glands.

Having completed its growth, the last instar larva stops feeding, becomes motionless and molts into last time. She turns into a doll.

Order Coleoptera, or Beetles. This is the largest group of insects, numbering about 360 thousand only known species, in general this accounts for about 40% of all known insect species.

Rice. 7. Characteristic signs Coleoptera

To get an idea of ​​how huge this group is, let's look at one simple example. All birds, fish, mammals, amphibians, reptiles, and many others belong to the phylum Chordata. In total, there are about 50 thousand species of representatives of the phylum Chordates. So, there are slightly more beetles from the Weevil family alone (Fig. 8), about 70 thousand species.

Rice. 8. Weevil

Coleoptera are very diverse, most of their species are still poorly studied. Therefore, it is impossible to definitively understand how many species still exist.

The first pair of wings of Coleoptera turned into hard elytra, which is where the name of the order came from. The elytra are attached to the middle thorax. They cover the hind wings and soft abdomen. The second pair of wings is thin, membranous and is used for flight. The wings are attached to the hind chest. Sometimes the wings and occasionally the elytra may disappear.

Rice. 9. Trilobite beetle

The mouthparts are gnawing (Fig. 10).

Rice. 10. Oral apparatus of odorous rove beetle

The transformation, as you already understand, is complete. It is obvious that with such a huge number, the appearance and body shape of the representatives of the order are extremely diverse.

Body length ranges from a fraction of a millimeter to almost 17 cm.

Rice. 11. Titan Lumberjack

The coloring can be both stunningly bright, warning (Fig. 12), and camouflage.

Rice. 12. Blister beetle

Moreover, some beetles are almost impossible to notice in their habitat.

Many species have bizarre growths on the body, modified limbs or jaws (Fig. 13, 14).

Rice. 13. Elephant beetle

Rice. 14. Stag Beetle

Beetle larvae also come in a variety of shapes, sizes and colors. They have a gnawing mouthpart (Fig. 15, 16). They have no abdominal prolegs. Beetle larvae, like other arthropods, grow using molts. The life of a larva can last from several months to tens of years.

Rice. 15. Ground beetle larva

Rice. 16. Longhorn beetle larva

Pupae are usually soft, uncolored (Fig. 17).

Rice. 17. Beetle pupa

Beetles are widely distributed throughout the world, except in very cold places. The order is most richly represented in tropical regions. Beetles have mastered all living environments. Their adults and larvae live on leaves and in plant tissues, in the soil and on its surface, in water and in many other habitats (Fig. 18).

Rice. 18. Rhinoceros beetle

Coleoptera can feed on anything: any parts of plants and any animals, mushrooms and carrion, manure (Fig. 19) and completely dry food supplies.

Rice. 19. Dung beetle

Many beetles have very interesting adaptations for protection from enemies. These include warning coloration (Fig. 20), protective coloration, toxicity, and protective behavior.

Rice. 20. Colorado potato beetle larva

Beetles can contact each other using chemical, sound or even light signals.

The importance of beetles is truly enormous. With their incredible numbers and diversity, they eat a huge number of plants and animals, as well as decaying debris. In turn, the adults and larvae of beetles also serve as food for all sorts of other animals. Many beetles from the families Lamellaridae, Click beetles, Weevils, Leaf beetles and Longhorn beetles are pests of agriculture and forestry (Fig. 21, 22).

Rice. 21. Colorado potato beetle

Rice. 22. Weevil

Some representatives of ground beetles and ladybugs, on the contrary, are capable of eating pests en masse. Some ladybugs They are even sometimes specially bred by humans to combat aphids (Fig. 23, 24).

Rice. 23. Ground beetle

Rice. 24. Ladybug eats aphids

Gravediggers and dung beetles are characteristic decomposers. They perform the function of orderlies, eating manure and carrion (Fig. 25).

Rice. 25. Dead-eating beetles

Order Lepidoptera, or Butterflies. These insects have wings covered with scales, hence their name. Scales (Fig. 26) are essentially flattened hairs.

Rice. 26. Scales

Butterflies have two pairs of wings. Depending on the shape, color and size of the scales, the wings have one color or another.

Rice. 27. Characteristic features of Lepidoptera

The development of butterflies proceeds with complete transformation. They go through the stages of egg, larva (Fig. 29), pupa (Fig. 30) and adult (Fig. 31). Butterfly eggs vary in shape (Fig. 28).

Rice. 28. Eggs

Rice. 29. Larva

Rice. 30. Doll

Rice. 31. Imago

The larvae are called caterpillars. Caterpillars, unlike butterfly imagoes, have gnawing mouthparts.

There are complex compound eyes, antennae and mouthparts. Oral apparatus different butterflies can be arranged in different ways. The most primitive representatives of the order have working upper jaws, or mandibles. , but there is no proboscis characteristic of the order as a whole. All other butterflies have a special proboscis, which they use to feed liquid food (Fig. 32). It is elastic and can curl like a spiral, and its length helps butterflies feed on nectar even from very deep flowers. In some butterflies the proboscis is absent for the second time. Often adult butterflies do not feed at all.

Rice. 32. Butterfly proboscis

The wingspan of butterflies ranges from 3 mm to almost 30 cm. In total, there are about 150 thousand species of butterflies (Fig. 33).

Rice. 33. Scoop agrippina

Butterflies are distributed all over the world, from cold tundras to hot deserts. In the mountains, butterflies are common right up to the border of eternal snow and ice. Due to active human economic activities that destroy their habitats, many species of these beautiful insects are in danger of extinction.

A caterpillar is the larva of a butterfly. It is usually worm-like, with a gnawing mouthpart, three short true legs and several pairs of pseudopods (Fig. 34).

Rice. 34. Caterpillar

The caterpillars of most butterfly species have silk-secreting glands, with which they create a cocoon before pupation. The food of caterpillars is mainly plant matter, occasionally wool and other horny substances. Sometimes caterpillars are even capable of predation.

Many caterpillars have bright colors, beautiful pubescence and outgrowths. The bright color warns of their toxicity. The pubescence, as a rule, is prickly and irritates the oral cavity of a predator that dares to eat such a caterpillar (Fig. 35). The outgrowths, as a rule, are also prickly or poisonous.

Rice. 35. Caterpillar pubescence

Caterpillars can defend themselves from enemies by pretending to be a dry twig or leaf, secreting a strong-smelling secret, taking a threatening pose, or simply descending sharply on a silk thread (Fig. 36).

Rice. 36. Caterpillar snake

In the butterfly pupa, only the abdomen is relatively mobile. Usually the pupa is inside a cocoon. Sometimes, as, for example, in daytime butterflies, the pupa is suspended from some support using a silk thread (Fig. 37).

Rice. 37. Wrecker doll

The first time after emerging from the pupa, the butterfly is not capable of flying (Fig. 38). She climbs to vertical elevations, where she freezes and remains until her wings spread. The spread wings harden and acquire their final color.

Rice. 38. Pupa outside the cocoon

An adult is an adult butterfly capable of reproduction. The main functions of this stage are reproduction and dispersal. The imago does not live long. She spends the nutrients that the caterpillar once accumulated. The average lifespan of an imago ranges from several days to several months.

Butterflies living in temperate latitudes oh, they need wintering. They usually overwinter at the pupal stage. However, there are species that overwinter at the caterpillar stage, and at the egg stage, and at the adult stage. If butterflies overwinter at the adult stage, migrations may be observed. Thus, the burdock that periodically appears in our country flies for the winter to southern countries - to Africa or Asia (Fig. 39).

Rice. 39. Burdock

When migrating, butterflies gather in huge flocks. Migrations over vast distances are known in the monarch butterfly. Our common butterflies, such as the wren, buckthorn, mourning butterfly and peacock's eye (Fig. 40-42), are able to overwinter in place as adults.

Rice. 40. Hives

Rice. 41. Krushinnitsa

Rice. 42. Peacock eye

After the snow melts, overwintered individuals are ready to reproduce. Adult lepidoptera are able to distinguish colors. Moreover, unlike us, they see perfectly well in the ultraviolet part of the spectrum (Fig. 43). By the way, scientists use this property when they need to collect butterflies for light. In addition to two compound eyes, some lepidopteran adults have two simple ocelli.

Rice. 43. Dandelion in the ultraviolet spectrum

Adult butterflies are the most important pollinators, and many plants are pollinated mainly or only by butterflies (Fig. 44).

Rice. 44. Common Tongue

Caterpillars can cause significant damage to plants, including those used by humans. Sometimes they are capable of leaving entire gardens and even forests without leaves.

Adults and caterpillars serve as food for many animals. Some types of butterflies can harm woolen fabrics, fur and food supplies. Individual representatives of the order are used to obtain silk, such as the famous Silkworm(Fig. 45).

Rice. 45. Silkworm

Order Diptera. As the name suggests, these insects have only two wings. But some mayflies and some beetles also have two wings. What is it about Diptera that is remarkable and why are they combined into one order?

Rice. 46. ​​Characteristic features of Diptera

The fact is that the hind wings not only disappeared, they were transformed into halteres (Fig. 47). These are special organs that dipterans use during takeoff and for stabilization in flight.

Rice. 47. halteres

Development in dipterans proceeds with complete transformation (Fig. 48).

Rice. 48. Complete transformation (diptera)

The oral apparatus of dipterans has a unique structure (Fig. 49).

Rice. 49. Mouthparts of Diptera

The upper lip, upper and lower jaws are elongated. They seem to be cutting.

All this is hidden in a kind of case formed from the lower lip. Moreover, with the help of such a lower lip, dipterans are able to absorb sugary liquids - drink, and with the help of their jaws and upper lip they are able to pierce the integument of a wide variety of animals and consume blood. Thus, it turns out that dipterans have two mouthparts in one: one of them is for sweet food, and the second is for blood. By the way, only females drink blood.

In many representatives of the order, only the lower lip remains of the oral apparatus. This happens, for example, in the housefly (Fig. 50).

Rice. 50. Housefly

The main feeding stage of dipterans is the larva. The larva is worm-like in shape, often with a narrowed anterior end. Sometimes its lifespan exceeds that of the imago. The adult performs mainly the functions of reproduction and dispersal. Adult dipterans mainly live in the air, while larvae inhabit a wide variety of habitats. They can live in water, in soil, in the tissues of plants and animals, and so on.

Diptera pupae are of two types. Pupae of the first type have clearly visible appendages, i.e. antennae, mouthparts, wings and legs, which fit tightly, as if glued to the body.

Pupae of another type are enclosed in a special shell - puparia. This puparia is formed from the modified molt skin of the last instar larva (Fig. 51).

Rice. 51. Larva inside the puparia

Diptera imagoes are inhabitants of the air. They feed mainly on sugary foods, such as flower nectar. Blood is used by females to mature eggs. However, there are also predators among the dipteran imagoes.

The antennae of dipterans can be short or long, and also have a very different structure. The legs of adult dipterans are usually armed with suckers, which allows them to move freely along vertical surfaces or even walk or hang upside down. Diptera are distinctly anterior-motor insects. Why? Because their hind wings are turned into halteres and are not used for movement. The middle chest, to which the working wings are attached, bears powerful muscles and is larger in size than the front and rear chest. About 150 thousand species of Diptera are known. This is very large detachment insects They are distributed almost all over the world. They are absent only at the very poles or high in the mountains. Some representatives of dipterans can easily be found even in the snow.

Adult dipterans can be important pollinators.

Larvae, such as flies, process organic matter found in animal excrement and carcasses.

There are many species of blood-sucking dipterans, some of which are potentially dangerous even to humans. They can spread various infectious diseases, such as sleeping sickness and malaria (Fig. 52, 53).

Rice. 52. Tsetse fly

Rice. 53. Deer bloodsucker

The most known to us, residents of temperate latitudes, representatives of blood-sucking dipterans are horseflies, mosquitoes, midges and woodlice (Fig. 54, 55).

Rice. 54. Horsefly

Rice. 55. Midge

Some dipteran larvae are capable of causing pathological growths in plant tissues, or galls, by their presence (Fig. 56).

Rice. 56. Gall midge

Ktyri are the most ferocious aerial predators (Fig. 57).

Rice. 57. Ktyr

Mining flies are capable of causing significant damage to plants (Fig. 58).

Rice. 58. Green-eyed

Dung, carrion and forest flies are, on the one hand, orderlies who destroy carrion, and on the other hand, they are carriers of many infectious diseases(Fig. 59).

Rice. 59. Dung fly

Rice. 60. Gadfly

As you probably remember, insect larvae with incomplete metamorphosis resemble adults. They have compound eyes, normal legs, and sometimes external wing rudiments. Such larvae, similar to the imaginal stage, are called nymphs. However, in some insects with incomplete metamorphosis, for example, mayflies, stoneflies, dragonflies, larvae live in water, and adult insects live in air. Therefore, the larvae cannot in any way resemble adults. They have provisional, i.e., larval organs. For example, the gills they need to breathe in water. Such specialized aquatic insect larvae with incomplete metamorphosis are called naiads (Fig. 61-66).

Rice. 61. Mayfly

Rice. 62. Mayfly larva

Rice. 63. Stonefly

Rice. 64. Stonefly larva

Rice. 65. Dragonfly

Rice. 66. Dragonfly larva

Some bugs are very difficult to eat. Thus, many golden beetles and bronze beetles have very hard, durable body coverings (Fig. 67).

Rice. 67. Bronzovki

Other beetles simply have spines on their front back or elytra. For example, some leaf beetles and longhorned beetles (Fig. 68).

Rice. 68. Longhorned beetle

Other beetles can fend for themselves well. Thus, many ground beetles, longhorned beetles and stag beetles have impressive and sometimes very dangerous jaws (Fig. 69).

Rice. 69. Horn beetle

Many leaf beetles and ladybugs are wastefully inedible to most predators. They have very caustic and sometimes downright poisonous blood.

The most poisonous when eaten are some types of blister and rove rove(Fig. 70). Their body fluid is so caustic that if it comes into contact, for example, with human skin, it causes burns and ulcerations.

Rice. 70. Blister

Some beetles have chemical weapons kind. These are glands that can produce pungent or unpleasant-smelling secretions. The most striking example of this type of protection is bombardier beetles (Fig. 71). If such a beetle is attacked, the beetle is capable of throwing towards the attacker a mixture of caustic chemicals heated to almost 100 degrees.

Rice. 71. Bombardier Beetle

Many ground beetles, including the widespread species of the genus Karabus (Fig. 72), are able to defend themselves from attack by spraying a liquid containing acetic acid.

Rice. 72. Karabus

And finally, many beetles do not have their own effective defenses, but seem to live under the auspices of protected insects. For example, in the nests of ants or termites.

Rice. 73. Rove rove

Athuloptera are a relatively small order of insects with complete metamorphosis. It has about 5 thousand species. They got their name from their mesh wings. Indeed, two pairs of wings of these insects are covered with a very dense network of veins. The color of lacewings is usually modest - soft green or brown. Although, sometimes it can be bright (Fig. 74, 75).

Rice. 74. Ascalafus

Rice. 75. Nymphida

It is interesting that sometimes lacewings have bright golden eyes, like the well-known lacewings (Fig. 76).

Rice. 76. Lacewing

The order Reticuloptera includes such insects as the same lacewings, antlions (Fig. 77) and interesting insects mantispas (Fig. 78).

Rice. 77. Antlion

Rice. 78. Mantispa

Reticulate insects are usually predators. In most cases, these are small insects ranging in length from several to several tens of millimeters. However, among the antlions there are also very large ones.

Rice. 79. Threadwing

The oral apparatus of the imago is gnawing. The oral apparatus of lacewing larvae is interesting. Their jaws grow together in pairs, forming, as it were, two hollow sharp tubes. Such a mouthpart works as a piercing-sucking one. The larva pierces its prey with its jaws and introduces digestive juice into its body, and then sucks out the liquefied contents of the victim with the same jaws. Thus, the digestion of lacewing larvae is external. Interestingly, in these larvae, undigested food remains are not thrown away, but accumulate inside the body. Excrement is thrown out only when the imago emerges from the pupa. Probably the most famous lacewing is the common lacewing. These insects are primarily nocturnal predators. It is not difficult to find them in the garden or at the edge of the forest. The animals are small, body length is about 1 cm.

Their small eggs on a graceful stalk can be found next to aphid colonies (Fig. 80).

Rice. 80. Lacewing eggs

The larva emerging from the egg immediately begins to feed. She still eats the same aphids (Fig. 81).

Rice. 81. Lacewing larva

Lacewing larvae pupate in an arachnoid cocoon, and it is interesting that they secrete silk not with the help of glands on the lower lip, like many other insects with complete metamorphosis, but with the help of Malpighian vessels (Fig. 82).

Rice. 82. Emergence of the imago from the cocoon

Predatory antlion larvae live in dry sand. Moreover, the larva digs a hunting funnel. The insect itself is located at its bottom, with its jaws out. When a small prey insect gets inside the funnel, the antlion larva, using its folded jaws together like a shovel, begins to throw sand at the victim. The sand seems to knock the small insect to the bottom of the funnel. When the prey is at the bottom of the crater, the antlion pierces it with its jaws and eats it.

The closest relatives of butterflies are caddis flies (Fig. 83). Caddis flies are a relatively small order of insects with complete metamorphosis. It includes about 15 thousand species. In appearance, adult caddis flies are a bit like small butterflies, only their wings are covered not with scales, like those of butterflies, but with hairs. Hence the Latin name for caddisflies, which can be translated as hair-winged. The wings of caddisflies are membranous, with the front ones being somewhat longer and stronger than the back ones. Adult caddisflies are found only near bodies of water where their larval stages live. The oral apparatus of adult caddisflies is reduced, greatly reduced, and practically only the palps remain.

Rice. 83. Caddisfly

Adult caddisflies do not feed, and therefore their lifespan is usually limited to one to two weeks. After mating, the female lays eggs, which are glued together with a special mucous mass. Eggs are laid on a stone or plant, in water or near water. The larvae, as we have already said, are aquatic. Often caddisfly larvae build special shelters - houses or covers (Fig. 84). To build their houses and covers, caddisflies use moss, blades of grass, pieces of dead wood, small twigs and other plant debris.

Rice. 84. Caddisfly larvae

Sometimes buildings may not even be made from plant remains, but, for example, from grains of sand and small shells.

In case of danger, caddisfly larvae are able to hide inside the house, plugging the entrance to it with a strong chinized head.

Caddisfly larvae and their homes are undoubtedly familiar to those of you who enjoy fishing. The larvae of some primitive caddisflies do not build houses, but build special trapping web funnels. The wide part of such a funnel looks upstream. All small living creatures brought by the current end up there. The caddisfly larvae eat these small animals. Caddisfly larvae pupate directly under water, inside their case.

Interestingly, the caddis pupa has broad paddle-like hind legs. Why does the pupa need wide rowing legs if the pupa is motionless? This is quite an interesting question. The pupa is indeed motionless, but an adult insect that has not yet left the pupa cover is quite capable of moving. It is this one, with the pupal covers put on like a suit, that, rowing with its hind legs, swims to the surface of the water and only there leaves the pupal skin (Fig. 85).

Rice. 85. Caddis fly pupa

Bibliography

1. Latyushin V.V., Shapkin V.A. Biology. Animals. 7th grade. - M.: Bustard, 2011.
2. Sonin N.I., Zakharov V.B. Biology. Diversity of living organisms. Animals. 8th grade. - M.: Bustard, 2009.

1. Insects ().
2. Files.school-collection.edu.ru ().
3. Files.school-collection.edu.ru ().

Homework

1. What orders of insects with a complete cycle of transformation during individual development do you know?
2. Name the representatives of the orders Coleoptera, Lepidoptera and Diptera that are found in your region.
3. What is the significance of the studied insects in nature and human life?
4. What animals from the orders Caddisflies and Reticulates are found in your region? Are there any protected species among them?
5. Discuss with friends and family the importance of sericulture for the development of civilizations ancient world. How did insects influence the course of history?