Absolutely all people at least once in their life met brown or red beetles with white spots in the form of triangles on their sides in the summer season. This is how the May beetle looks, in length it is quite large - about three centimeters, and convex in width. If you touch the May bug with your fingers, you can feel its hard shell made of chitinous "shell".
The body of the beetle is divided into three components: head, abdomen, chest. A similar structure is characteristic of all other insects. Chafer beetle is an arthropod type, and in Latin its name is denoted as Melolontha Hippocastani. The first word refers to the genus of the beetle, which consists of twenty-four species, and nine of them live in Russia.
Mass reproduction of beetles, as the name implies, falls on May. At the same time, the buds of oaks and birches begin to blossom. May bugs grow underground, and when a certain period is reached, crawl out of the soil and immediately soar up. We can hear their buzzing in the evenings among flowering plants. True, May beetles are not useful for agriculture: they deal with damage to young foliage. By the way, in the afternoon, beetles can not be found among the vegetation, as they sit on shrubs or trees and merge with the branches, snagging on their feet.
Appearance and habitat
What does the May bug consist of? Like all insects, the structure of the May beetle includes a chitinous coating in the form of a shell, which plays the role of protection against environmental stimuli, and also acts as a kind of skeleton. The maximum size of the beetle is usually up to three and a half centimeters.
Adult representatives of the May beetle often differ in color. Two variations are distinguished from the whole color gamut: rex - a red body with a red tint of the legs and pronotum; nigripes - legs and pronotum black. Such chromatism is considered the ecological form of the structure of the May beetle. Those individuals that are red and orange in color live in places open to the sun, while black individuals mostly live in dark places of medium-dense forests. Accordingly, red prevails in the south, and black in the north of the country.
Being a part of the world of insects, the May beetle prefers forest-steppes and forest belts with pine young growth, in urban areas they are found among artificially planted plants, as well as among trees and shrubs that are flowering and fruitful. It is the trees and shrubs that are considered the main place for mating, after which the female creates the egg laying in the soil, burrowing there with her head.
Beetle body parts
The external structure of the May beetle is identical to the structure of other beetles. In addition to the main parts of the body, it has a pronotum, which, together with the head, is covered with medium-length hairs, relative to the rest of the hair, they form stripes along the body. The underwing region is also covered with small hairs. The very part of the body to which the legs are attached, and the head has small scales similar to hair. All limbs are divided into separate members, hence the name Arthropods. The chest has 3 segments, and the abdomen is eight.
May bug head
The head includes the oral apparatus of the May bug, as well as the senses. Diametrically in the front part there is a place for the upper lip, behind it there are jaws, both from below and above the inner part of the oral cavity, as well as the lower lip. Jaws are the lateral and lower borders of the mouth. The lower jaw and lip are equipped with probes, which are used for touch and as taste buds.
The eyes are located on the left and right of the head, the structure of the eyes is complex faceted - they consist of thousands of ordinary small eyes. To smell, the May bug uses a pair of antennae, at the end of which there are wide plates. An interesting fact is that these antennae are more hypersensitive in the male. The head itself is pressed in front, as if inside a beetle, that is, it will be able to tilt its head, but it will not be able to make a turn with it.
May bug structure: chest
One of the most interesting places of the bug is where the legs grow from. The thoracic section of the external structure of the May beetle is divided into three parts: front, middle and back. And to each part of the thoracic region, legs are attached in pairs - only six legs. Plus, on the back and middle section there are wings. The prothorax can be distinguished on the back, and everything else is closed with the help of elytra, quite rigid in composition, along the elytra there are ribs. These are actually modified front wings.
The elytra in the external structure of the May beetle play the role of protecting the hind wings, which are webbed in structure, as are the parts of the abdomen from the back, where the beetle has sensitive soft tissues. It is such elytra that are the hallmark of all beetles, hence the name Coleoptera.
Before taking off, the beetle spreads both elytra cups in different directions, folded wings go out and spread out from under them, after which it can take off. Rigid elytra play the role of the monoplane wing of the aircraft and its tail, while the thin wings themselves perform the work of engines.
Butterflies, dragonflies and bees, for example, have wings in the amount of four pieces, but without protective "shutters", that is, they are all of the same thin density. Cockchafer uses wings not only to cover distances in search of food, but uses them to attract females.
Most adults of the insect order are “equipped” with wings, but in some species such an aircraft is still missing, for example, in fleas, lice, bed bugs. In fact, their predecessors had wings many years ago. Life as a parasite brought this organ out during evolutionary processes.
If you look at the abdominal part of the beetle, you can clearly see all three departments, how they are connected and how the legs are attached. Small claws are on the feet of the May beetle, it is with them that he clings to the branches and expertly moves through the trees. But on a flat surface the bug moves much more slowly.
What does the abdomen consist of?
The abdomen and chest of the insect are connected together and are not able to move separately from each other. The detailed structure of the May beetle can be seen if you look through the bottom of the body. Eight segments of the abdomen are hidden under the elytra, only the sharp end is noticeable.
If you carefully raise the elytra and spread the thin wings, spiracles can be seen on the edge of the back - these are small holes in the body of the insect, the meaning of which will be revealed later, while describing the internal structure of the May beetle and its life systems.
Digestive system
What does the may bug eat? With the sharp ends of the upper jaw, he gnaws the sheet into pieces, and grinds everything with the lower jaws with serrated edges. Therefore, this structure of the jaw has a definition - gnawing. Everything that the beetle swallows enters the gastric section, which, in turn, is equipped with chitinous teeth, they grind food and send it to the intestine, where the process of final digestion takes place. In the intestine, food is absorbed, and its residual part is excreted through the anus - the anus.
It is interesting to observe the evolutionary change in the oral cavity of insects - those who need to absorb food in a liquid state have a proboscis with which they draw it into themselves.
Digestion chain
The development of the May beetle is such that it needs solid plant-based food. The movement of food from the jaws begins, then it enters the throat and esophagus. The long esophagus has a special extension called goiter, from where food passes into the chewing stomach system. After grinding, the food enters the middle intestine, where the digestive juices are finally digested and distributed into waste and useful substances.
Since the beetle sticks its food into the mouth with the help of palps (oral appendages), the insect simply cannot survive without these paired organs.
The structure of the circulatory system
The circulatory system in all arthropods is open. That is, blood is located between the internal organs of the May beetle, it flows around all internal tissues, thus delivers useful substances and takes away waste products from the internal part of the body. The blood of the beetle does not carry oxygen, that is, it does not participate in the respiratory process.
A muscular tube pushes blood to move, this is the so-called heart of a beetle, it is located along the back above the intestine. The tube pulsates very often, thereby providing blood to the head. The heart has valves, they do not allow blood to flow back from the head. When the tube expands, blood flows from the posterior section through the sides (special holes), where the valves are located. In the body itself, blood circulates according to the front-back pattern, that is, first it travels from the front to the back and, pouring into the heart, rushes back to the head.
Respiratory system
Respiratory processes occur due to trachea, the latter are represented by tubes and densely fill the entire inner space of the beetle. It is through the trachea that organs and tissues are fed with oxygen, and external air with oxygen gets through those very spiracles, about which it was mentioned above. All spiracles are connected to each trachea.
Highlight system
Malpighian vessels are a bundle of a group of ultra-thin tubes and are located in the oral cavity, they are called the excretory system. These tubes hide their bases in the intestines, all the bodies of the tubes filter everything in the intestine and convert the products for excretion into crystals. Such crystals return to the intestine, where they are discharged with undigested particles. But toxic substances can accumulate in the fat pad.
Beetle nervous system
The development of the May bug can not occur without the nervous system, which is a ring near the pharynx and a nerve chain in the belly. Due to the conjugation of nerve cells in the head, the brain of an insect is obtained. Those insects that lead a complex lifestyle: ants and bees - have an enlarged brain, the remaining internal nerve nodes are expanded due to their coalescence.
Reproductive system
The internal structure of the May beetle suggests a system responsible for the reproduction of the insect. In the female, the appearance of the reproductive system is a complex of two ovaries, where eggs are formed. The ovaries have oviducts in the form of tubes, at their base they form one large tube through which all the eggs exit the female.
The reproductive system of the female is also equipped with a testis. This is the internal container where all the sperm from the male are collected. Those eggs that are already ripe for fertilization can begin the process of forming a new life.
In males, spermatozoa form in the testes, there are only two of them. The vas deferens depart from them, and finally the spermatozoa exit through the ejaculation channel. He does not have a pair.