Table "Insect orders" (names, description, characteristics)

Insects are a class of arthropod invertebrate animals. According to the classification in force today, they, along with centipedes, are included in the subtype of tracheoides. The name of the class is derived from the word "cut". With the French "insecte" and Latin "insectum" the concept is literally translated as "an animal with notches." Consider these representatives of the fauna in more detail. At the end of the article the table "Insect orders" will be presented.

General information

On the body of insects there is a chitinized cuticle. It forms an eco-skeleton. The structure of insects is quite simple. There are three departments: head, abdomen and chest. Considering the structure of insects, three pairs of legs stand out. They are attached to the thoracic area. In many groups, a pair of wings is attached to its second and third segments. Body size varies from 0.2 mm to 30 cm and more.

Life cycle

It includes embryonic development of insects. It is called the "egg phase". A postembryonic period is also distinguished. It is accompanied by metamorphosis. It can be of two kinds. Depending on this, detachments of insects with incomplete transformation are isolated. They pass through phases of eggs, larvae and adults. Completed metamorphosis is characterized by four stages. In this case, the development of insects includes the phases of eggs, larvae, pupae and adults. The first larvae have an external resemblance to adult individuals. The difference between them is the size of the body, the rudimentary state or the complete absence of wings and genital organs. Larvae of animals passing through four phases have a worm-like shape. Only in adult individuals all the necessary signs of the detachment appear. At the stage of imago, there is dispersal and reproduction. To the class of insects are the most diverse creatures. More than one million species are described. They are considered the most numerous group of animals in nature and occupy all kinds of ecological zones. They are found everywhere, even in Antarctica.

Metamorphosis

The overwhelming majority of insects with a complete transformation in their development passes through four phases. However, there are exceptions in nature. For example, the blisters note the so-called hypermetamorphosis. It involves five, six or more phases. They are represented as special (additional) larval stages. Each such stage is called a triungulin. Another exception is neoteny. This term denotes the ability to reach maturity and multiply in the larval phase. Thus females do not pass at once two stages: pupae and imago. As for males, they can develop in the usual cycle.

Insect groups with incomplete transformation

In most of these animals, the larva and the imagos have much in common. The first are represented by quite diverse forms. Experts unite them into two main groups. The first includes larvae, similar to adults, in the second, respectively, different from them. The first called nymphs, and the latter - true. Larvae may have similarities with adults in both biological and morphological terms. As a rule, they live in the same environment, similarly eat. In true larvae, there are sharp differences from imago in appearance, distribution area, food. In order for them to become adults, they must go through the phase of the pupa. For some species is characterized by the so-called intermediate stage - subimago. As a rule, it takes place in the development of aquatic animals. Individuals at this stage have signs of adults, but they have not yet reached sexual maturity.

Biology: detachments of insects. Cockroaches

A typical representative is a red cockroach. It is believed that the appearance of such insects in the house indicates the slovenliness of the owners. These animals leave shelter at night. Their main food is incorrectly stored products. The females of the cockroach at the end of the abdomen have an ootheque - the so-called egg case. They throw it into the garbage. From the ooteca develop eggs, from which, respectively, there are larvae. They differ in white color and are similar to adults. Afterwards they darken.

Termites

Table "Detachments of insects" characterizes these animals as public. They live very large families. A feature of termites is the division of labor. In the families there are males, workers, soldiers, "queens" (females). Termitniki (nests of insects) can reach impressive sizes. For example, in African savannahs one can find giant nests up to 10-12 m. The underground part can reach a diameter of 60 m. The main food product of termites is wood. They damage wooden structures, agricultural crops. At present, about 2.5 thousand termites are described.

Lice

Witless parasites are included in this unit. These animals parasitize on mammals and humans. The head louse lives in the hair and sticks nits to them (the so-called eggs). Fat insects live in folds of clothing. They lay their eggs directly on the fabric. The larvae emerging from them do not differ externally from the adults. Female lice are considered very prolific. For a month they can produce offspring of several hundred insects. Being external parasites, louses have a number of features. For example, there are tenacious claws on their paws, they do not have wings, as they do not need them. Mouth apparatus lice prickly-sucking. These animals are carriers of various diseases. One of them is typhus.

Bedbugs

Table "Insect groups" includes in this category a variety of pests of agricultural crops. One of the known is the bug-bug. It sucks the contents of the grain from cereals. In residential areas you can find a bug-flea. This insect creates a lot of inconvenience for a person. In fresh water bodies, there is a bug-water meter. It eats insects that fall into the water. There are among the bedbugs and predators, for example, bug-gladun. It attacks fish fry and various invertebrates. All members of this group are called semi-feathery insects.

Other categories

Anamorphic insects prefer to feed on plant juices. In this category, for example, include aphids. It exists in nature in a variety of forms and causes significant damage to crops. Anaerophagous insects are considered carriers of viral diseases, dangerous for plants. For example, among them there are various cicadas that can reach large sizes (up to 5-6 cm). The order of orthopterans includes mainly herbivorous insects. However, you can meet among them and predators. For example, representatives such as cabbage, locusts are sufficiently known. A grasshopper is included in the group of orthopterans. It lives in the grass, in the steppes and in the meadows. It has a clavate, long ovipositor. The cabbage rolls well and flies, has digging feet. It causes great damage to underground parts of plants that grow in the garden (cucumbers, potatoes, carrots, cabbage, etc.). Some species of locusts are characterized by mass reproduction. In such cases, they gather in huge flocks, fly away for a long distance (up to several thousand kilometers). At the same time along the way they destroy all the cultivated plants. In the group of headstock includes predatory insects. Their names are quite interesting. For example, a grandmother-beam, dib-dazoretsi and others. They are considered the best flyers. They are very maneuverable. They can hang in the air, exhibit exceptional mobility, develop a high (up to 100 km / h) speed. On their prey they attack directly in flight.

Beetles

These are hard-winged insects. They are considered the most numerous community of all. Their number reaches 300 thousand species. Beetles live in a variety of conditions of fresh water and land. Dimensions of their body vary from 0.3 to 155 mm. Many hard-winged insects inflict great damage on crops. In the world, for example, the Colorado beetle is known. He was brought to Russia from America. Beetle-kuzka damages crops. Beet weevil damages sugar beet. Larvae of the May beetle damage potato tubers and tree roots. Known also bark beetle. It drills in bast fibers and bark moves, damages precious rocks. Many representatives of the detachment are harmful to food reserves. For example, such are the pea grain, the beetle-bug beetle, the bug-bread grindstone. As part of the detachment there is also a pipe-screw. In spring, this beetle cuts the leaf to the main vein in a special way. Part of the plate withers and loses its elasticity. The beetle folds and lays eggs there. So he takes care of the offspring. Present among the beetles are useful insects. The names of such species are gloomy. For example, beetles-grobariks and pushers. Many individuals are very beautiful externally and can reach impressive sizes. Such, for example, are considered stag beetle and stag, which are listed in the Red Book.

Butterflies

They are lepidopteran insects. These animals have a number of distinctive features. One of the main ones is the diverse color of the wings. The group includes: cabbage, urticaria, silkworm and others. In the Far East, you can meet quite large representatives of the detachment. As a rule, these are night butterflies. The wingspan reaches the width of the unfolded notebook. Scales on their surface have the ability to refract light. Due to this, the color becomes iridescent. Larvae of butterflies are called caterpillars. They differ in a long body and have a gnawing apparatus. Salivary glands secrete silk threads. Of them, before the pupation, cocoons are woven. Adults are considered to be excellent plant pollinators. Most caterpillars eat leaves. This they cause great damage to cultural plantings. The main parasites, for example, are the apple moth, the cabbage whortle, the ringed silkworm, the golden-goat, etc. Some caterpillars damage food products, spoil the flour. Oak and silkworm are bred for obtaining silk.

Group of various species

Hymenoptera insects are bees, riders, wasps, bumblebees, sawflies and others. All these animals lead a different lifestyle. Some representatives are herbivorous. Their larvae cause significant damage to cereals and other plants. Such, for example, are pine and bread sawflies. Their larvae are very similar in appearance to butterfly larvae. In this regard, they are often referred to as false caterpillars. The sawflies possess a very specific ovipositor. It is intended for sawing pockets in plant tissues, in which females lay eggs.

Bumblebees

They are very good pollinators. These hymenopteran insects are considered to be social. Their families exist only during one summer. Their nests they arrange in hollows, nests, birdhouses. The construction is carried out by a female. She equips the wax cells to lay eggs. In each of them is placed a supply of food - pollen, mixed with honey. Appearing larvae eat the stock, after 2-3 weeks begin to weave cocoons and turn into pupae. Out of them come working bumblebees, males and females. By the end of the season in a large nest can be up to 500 individuals. By the autumn, the old uterus, the workers of bumblebees and males die. Young females are hiding for the winter.

Bees

They bring the greatest benefit from all the social Hymenoptera insects. Honey bees are considered excellent pollinators. They produce very useful for human products: honey, royal jelly, wax, propolis. They are used for food, they are in demand for cosmetology, medicine, in the manufacture of perfumes, paints, varnishes and so on. In the bee family, all members closely interact with each other. It is impossible to flourish without the drones and uterus, working individuals.

Mosquitoes

These are dipterous insects. There are common and malarial mosquitoes. Their distinctive feature is the presence of one transparent pair of wings. The second pair turned into a "buzz". The habitat of a simple mosquito is a damp, swampy terrain. They become especially numerous by the middle of summer. The oral apparatus is equipped with a thrusting proboscis. With his help, they pierce the skin and suck blood. The larvae of mosquitoes have a worm-shaped form. They live in stagnant water. There they develop, eat, gradually turning into pupae. They, in turn, also remain in stagnant water. However, since they can not eat, they soon become adults. Ordinary and malarial mosquitoes differ in planting. The first holds the body parallel to the surface on which it sits. The malarial mosquito high up the back.

Flies

These are also dipterous insects. They, unlike mosquitoes, have short antennae. Their larvae are white, usually headless and legless. They have a worm-like shape. Larvae of the housefly live and develop in sewage, manure piles, kitchen garbage. Here the female lays eggs. The larvae crawl out of the waste before pupation, penetrate into the soil, where they turn into pupae. Adult individuals fly everywhere and search for food. From the cesspools they fly over to food products, carrying microbes and pathogens of dangerous gastrointestinal diseases.

Other groups

There are in nature retina-winged insects. This is a relatively small group in its size. It has about 6 thousand species. Such insects have an elongated body with soft covers. Their coloration is brown or gently green. Two pairs of their wings are covered with a network of veins. This group includes such representatives as ant lions, lacewings, and mantises. The most part of the retina is the predator. They first appeared in the Permian period. The subsequent formation of the group was influenced by geological and climatic changes in the Mesozoic. Insect dragonfly is considered a very good flyer. These animals have a relatively large body. Their head is mobile, large eyes are on it. The insect of the dragonfly lives mainly in humid subtropics and tropics. In the Russian Federation it is distributed practically on all territory (except for arid areas).

The scheme

The following table, "Detachments of insects," briefly characterizes the characteristics of some of the animals discussed above.

Natural enemies

These are various pathogenic microorganisms, predatory and parasitic invertebrates. Insects also feed on many vertebrates. Natural enemies (entomophages) can destroy them at any phase of growth. Today there are microorganisms that act as different pathogens for viral, bacterial diseases of insects.

Currently, more than 400 species of fungi that can cause these or other pathologies are described. A fairly large group of natural enemies of insects are parasitic worms that provoke nematode diseases. Among invertebrates hunting for the animals in question, it should be noted arachnids (scorpions, spiders, phalanges, ticks, etc.), millipedes. Of the vertebrates, the danger is represented by different species of fish, amphibians. For example, the diet of frogs is 95% of insects. Natural enemies are also birds, reptiles, mammals. In particular, bats, tubercles, anteaters and others are dangerous for insects. Within these groups there are entire communities specializing exclusively in these animals. The number of insects on the planet reaches 90% of all living things. Their role in nature is extremely important. According to biomass, herbivorous insects are several times higher than other phytophagous animals. This is due to the fact that they consume the bulk of plant growth. Parasitic and predatory insects are considered natural regulators of populations of those organisms that act as their main food. They themselves are food for many vertebrates and invertebrates.