Insects are a class of invertebrate arthropods that live almost anywhere on the globe, with the exception of the extreme Arctic and the tops of the highest mountains, forever covered with snow. Scientists say that where there are plants, especially flowering ones, you can always find at least one type of insect. It is almost impossible to count invertebrates of this class, but it is estimated that there are from 100 quadrillion to 10 quintillion of them on Earth. It’s hard to imagine such a number of individuals, but there really are so many insects.
Who are insects
The science of insects (entomology) and biology say that these representatives are the largest class of animals that inhabit the entire planet. Therefore, their habitat is diverse.
Blind
They can be found in the air, in forests, in water bodies, on the ground, in the desert, on ice and other surfaces. Each of them has its own distinctive features.
Dust mites
Microscopic arachnids
,
the size of which does not exceed 0.3 mm
.
This is a person’s constant neighbor, whose existence many do not even know about. The basis of dust mite nutrition is dead human skin
. It does not directly harm people, but with a high population, allergic reactions to its secretions are possible. It is impossible to completely remove dust mites; you can only reduce their numbers. To do this, you need to frequently wet clean the places where dust accumulates, vacuum and wash the bed regularly, clean upholstered furniture and outerwear. You can also periodically treat surfaces with special products.
Signs of insects
Many beginners are interested in the main characteristics of insects, how many legs they have and other parameters.
Weevil beetle
They differ from each other in external and internal structure. But they all have common characteristics:
- presence of 6 legs,
- the presence of notches on the body,
- presence of a head with a chest and abdomen.
A schematic drawing of the external structure is below.
Silverfish
This representative of the bristletail appeared in the tropics. And in apartments, the silverfish chooses places that remind it of its ancestral home - with high humidity and temperature
.
She is nocturnal and does not tolerate bright light
. The silverfish does not fly, but runs quite quickly. Its appearance resembles ancient crustaceans - a spindle-shaped, flattened body, divided into segments. Feeding on sugar, flour, wood glue, paper and leather, the insect causes harm, albeit minor. Silverfish damage only becomes greater when the insect population increases greatly. Moreover, it is difficult to track this, since they are extremely secretive animals. To eliminate insects, repellents, traps and some chemicals are used.
Types of insects photos and names
Insects are arthropods. These teams of specialists number more than 3.5 million. We present the most popular varieties in the world with photographs below in a list.
Herbivores
Herbivorous species, as their name suggests, eat plants, pollen, and plant sap. These include stick insects, cicadas, dragonflies, butterflies, aphids, bees and leaf beetles.
Philippine stick insect
Stick insects love to camouflage themselves. They can hardly be distinguished among the leaves and tree trunks.
Black Sea cicada
Small and large representatives of cicadas eat plant sap, and also communicate loudly with each other and chirp.
Amazing, orthoptera and coleoptera butterflies allow them to pollinate flowers, flying from one flower to another, drinking nectar using their proboscis.
Predatory
Predators attack other individuals or eat their larvae. Examples: these include praying mantises, ladybugs, dragonflies, swimming beetles and ground beetles.
Mantis
The praying mantis skillfully camouflages itself and waits for the moment to attack its prey, and then attacks and eats it.
Dragonfly with prey
Dragonflies, like ladybugs, fly quite quickly, hunt mosquitoes, eat their eggs and other arthropods.
Dimensions
Stick insects are one of the largest insects.
As mentioned above, there are many insects in the world that are completely different from each other. Thus, both the flea and the butterfly are representatives of the same class, but outwardly they have little in common, differing primarily in the size and shape of the body. If we talk about dimensions, the largest of the existing invertebrates is the stick insect. The length of the individual discovered in Kalimantan is over 35 cm. Previously, a stick insect was discovered whose size, including its limbs, exceeded 52 cm.
Interesting: Instinct in insects
The fossil taxa were also quite large. The body length of Meganeura was 50 cm, while its wingspan reached 70 cm.
Among beetles, the largest representative of the species is the Hercules beetle. Males of this species reach a length of 17 cm. The titan lumberjack, which lives in South America, is not inferior to Hercules. Its body length exceeds 16 cm.
There are giants among butterflies too. The scoop tizania agrippina has such large volumes that from a distance it can easily pass for a bird. Its wingspan is 28 cm. This is a nocturnal insect, it is almost impossible to see it in the daytime. The largest diurnal butterfly is Queen Alexandra's Ornithoptera (27.3 cm).
The owner of the smallest body is the male parasitic ichneumon (0.0139 cm). Among non-parasites, only the feather wing of the tribe can boast of small size (less than 1 mm).
Classification of insects
Insects are primarily wingless and winged. The first ones never had wings. They live on the ground and eat what they can find on it.
Winged creatures, on the contrary, feed on what they can find in the air. They are further divided into two subspecies with complete and incomplete transformation.
The difference is that the former develop from an egg and only become larger in size, for example, a grasshopper, while the latter mature in cocoons, like butterflies or silkworms.
What do they eat
A grasshopper eats grass.
Different types of insects use organic substances as food, for example, tissues of animals and plants, waste products of other creatures, and remains. At the same time, insects, as a rule, are not omnivores and feed on any one type of organic matter, choosing between animal and plant origin.
Herbivores are called phytophages, those that feed on carrion are called necrophages, and plant debris on the soil surface are called detritivores. Interestingly, belonging to the group of herbivorous individuals does not mean at all that insects can feed on any parts of the plant. Among them there are those who feed only on leaves (phyllophagous), seeds (carpophagous), wood (xylophagous), and roots (rhizophagous). There are gall formers, among predators and parasites there are blood-sucking, ectoparasites and endoparasites. But this is not the final division. Everything described is classified as food specialization of the first order.
Some insects have unusual food preferences, for example, the tobacco beetle larva eats tobacco leaves and is therefore considered a dangerous pest.
The structure of insects
Any arthropod consists of a head, thorax and abdomen. Each part of the body has its own appendages that are responsible for the ability to see, hear, touch, communicate, reproduce and move.
The head contains the organs of vision, mouth and touch. There are legs and wings on the chest. And the abdomen contains the main internal organs responsible for the development of the animal.
Communication
Cicadas are known for their singing.
Insects communicate with each other using sounds, light and contact signals and pheromones:
- Sounds. Many insects are able to produce and detect sound signals. This allows them to navigate in space, find representatives of their species for mating, and even scare off enemies. Sounds are produced by systematic impacts of different parts of the body on the substrate. But, for example, cicadas have timbal membranes that help them produce high-pitched calls that resemble screams. Grasshoppers, crickets and mole crickets rub their wing covers against each other. The result is a chirping sound.
- Contact signal. Characteristic of well-organized social insects, such as bees. Having discovered a source of food, the scout bee begins to perform something like a dance, luring its companions in this simple way. Ants use antennas on their heads to transmit signals.
- Glow. Most Coleopteran insects glow in the dark. They use light signals to search for food or call a partner. At the same time, the light does not have to be white or yellow; some fireflies alternately emit light of red and green shades.
Pheromones are used for the sole purpose of attracting individuals of the opposite sex. But some insects can emit certain odors when a predator approaches, scaring them away and driving them away.
Interesting: Ladybug - where it lives, structure, migration, what the dots mean, photos and videos
Insect Reproduction
Insects, such as praying mantises, cockroaches and bedbugs, reproduce using droplets of sperm left on the ground.
Others mate with each other, undergo the process of copulation, as a result of which eggs appear.
Already from the eggs offspring appear.
Food moth
The subject of food moth attacks are all kinds of cereals, dried fruits or nuts
.
It does not have a silvery tint on the wings, is smaller than the clothes one, and the overall color can vary depending on the species. The larva is a small, white worm. If flying small moths are found near food storage areas, it is necessary to immediately inspect the stored cereals, flour, pasta, nuts, etc., especially those that have not been used for a long time
. If larvae and cocoons are found, it is better to dispose of the products in which they are found. Storage areas should be thoroughly washed and treated with special products.
Life cycle
Conventionally, the life cycle of any insect is divided into three stages. In the first stage, an embryo appears and develops in an egg. In the second stage, the embryo emerges into the light and reaches the imago.
And at the last stage, the adult animal reaches maturity, lays eggs, leaving offspring, and dies.
Each insect has its own life cycle. It depends on the composition of the generation, the type of reproduction and the type of life activity.
clothes moth
Clothes moths are widespread throughout the world. Spoiled clothing made of wool or silk is the calling card of the caterpillars of this inconspicuous moth. At dusk or when you turn on the lights at night, you can sometimes see a small butterfly fluttering around the apartment. These are, as a rule, males who do not pose any particular danger and do not have a gnawing mouthpart. Females lay eggs in the folds of clothing made from natural materials. This requires three conditions - absence of drafts, humidity and comfortable temperature. Therefore, closets with winter clothes that are rarely opened in the summer are an ideal place for moths to develop. As a preventive measure, we can recommend regular ventilation and drying of linen and wardrobes. Scent repellents work well:
- citrus peels;
- dry lavender.
In case of severe damage, it is already worth using strong insecticides. Some products, such as Dr.Klaus moth spray, have a combined effect. It can be used both for the destruction of moths and larvae, and for repelling with a long period of action.
Interesting facts about insects
May beetle in flight
A few more interesting facts for children and adults:
- The fewest living creatures in the world are mosquitoes and flies. They develop the fastest and lay eggs.
- Today, scientists are increasingly coming to the conclusion that there are more than 8 million species of insects.
- Every year new species of arthropods are identified and recorded in books.
- Spiders eat every year as much prey as the entire population of the planet weighs.
- Rare species were captured by researchers only once.
- Insects do not have a skeleton. Its role is assigned to the external chitinous exoskeleton.
- Mosquitoes can completely suck human blood. Moreover, their numbers must be enormous.
- Scientists are unable to solve the mystery of the flight of beetles, since according to all laws they should not fly.
- The fastest moving insect on earth is the dragonfly. She flies at a speed of 60 km/h.
Ants
The ants themselves do not pose a serious danger, but the huge number of small insects scurrying around causes discomfort. Moreover, they penetrate into the smallest crevices and get into almost all products. Some species inflict quite painful bites
.
Mostly black, red and red ants
.
The life of all ants is built around the “queen” - the main female who reproduces offspring. Therefore, if there are a lot of ants, by following their path, you can find the place where the main nest is located
. The destruction of the colony must begin from this place, since the fight against single ants is ineffective. To remove these insects, boric acid baits, traps and crayons are used. However, such methods do not give quick results. If you have been able to reliably establish the center of the colony, it is better to treat it with modern aerosols or sprays.
Bee
The importance of bees can hardly be overestimated, because these hardworking insects pollinate plants and produce honey, which is used in cooking, for cosmetic purposes, and for the treatment of diseases. And other beekeeping products - bee bread, propolis, royal jelly, bee venom - are no less useful. All of them are natural antibiotics.
Pollination of plants by bees improves the quality of seeds, increases the size, juiciness and taste of fruits
Even beehives and dead insects are beneficial. Wax is made from honeycombs, and medicinal tinctures are made from bee pestilence.
Centipede
In damp and warm basements, in sewer niches, and attics, you can find these relatives of insects, quickly rearranging several pairs of legs. Centipedes, or more precisely centipedes
, include hundreds of species, many of which can be found at home.
They pose no danger to humans , although they can bite sensitively if disturbed
.
Their main food is rotting vegetation or other invertebrates
. If you don’t like such tenants, you should clean and ventilate technical rooms more often.
Brief description of the class
Despite the diversity of species, representatives of the class have a number of common characteristics.
| Characteristic | Peculiarities |
| Cover | External chitinous skeleton |
| Body parts | Head, chest, abdomen |
| Limbs | Three pairs of walking legs |
| Wings | They represent outgrowths of the body wall along the lateral edge of the dorsal sclerite. Wing muscles are missing |
| Habitats | All |
| Oral apparatus |
|
| Digestive system | Anterior, middle and posterior sections |
| Respiratory system | Tracheal system |
| Circulatory system | Unclosed. Two-chambered heart |
| Excretory system | Malpighian vessels and fat body |
| Nervous system | Periopharyngeal nerve ring and ventral nerve cord. Faceted vision. Organs of smell and touch - a pair of antennas |
| Reproductive system | Dioecious animals. Characterized by sexual dimorphism |
Among Insects there are herbivorous and parasitic forms, as well as predators. The type of nutrition depends on the structure of the oral apparatus.
