Bordered swimmer

Bordered swimmer. All about the life of a water bug

Beetles or beetles are one of the most numerous orders of insects by the number of species. They mastered the air, land, underground, aquatic habitats.

One of the usual water beetles is the fringed swimmer, which lives in small reservoirs with fresh water. Settles in ponds, lakes, in river backwaters, in ditches filled with rainwater, in swamps. It belongs to carnivorous insects and is part of the family of swimmers.

The body shape of the swimming beetle is streamlined, the legs are of a swimming type with small comb brushes at the ends of the legs.

The breathing holes are hidden under the elytra. The beetle swims beautifully in water, this is its native element. On the water surface of a small pond, you can often see how a large and dark beetle swims up. It hangs in water, exposing the end of the abdomen to the surface. Then he quickly dives back, releasing a bubble filled with air.

Banded swimmer (Dytiscus marginalis).

The fact is that the swimmer breathes atmospheric air and needs to replenish oxygen reserves in the body. The ancestors of the beetle were terrestrial organisms, therefore, this feature is present in the swimmer. To replenish oxygen reserves, he first squeezes the exhaust air out of the respiratory tubes — trachea, and then draws in a new portion of the respiratory mixture with a high oxygen content.

Alternating exhale and inhale, the swimmer constantly updates the composition of the gas necessary for breathing.

Looking at the bug, you can see how the abdomen moves, then expands, then falls. Air is also stored under the elytra, and if the swimmer does not have time to get to the surface of the reservoir, he uses this reserve. It sits on the stem of an aquatic plant, protrudes its hind legs and squeezes a bubble of air from under the elytra. A bubble filled with air necessary for breathing underwater hangs at the end of the abdomen and does not come off. But the volume of air is quite small and quickly consumed, but there is more oxygen in the water, then the gas begins to flow into the air bubble from the water.

Swimmers can fly well, but they do it rarely, basically, there is a need to move to another reservoir.

The beetle sits calmly under water and breathes. According to physical laws, due to the difference in concentration and pressure, oxygen enters the respiratory organs of the swimmer. Then it goes through the respiratory tubes further into the beetle. Pressure equilibrium is not established, and oxygen freely enters. Only the farther from the bubble, the less oxygen, but this allows the bug to survive a dangerous moment and to remain under water for a long time without floating to the surface.

And if there is a need to swim in search of food, the swimmer draws the bubble in and swims. He gets tired, sits down again under water on a plant and forms an air bubble. In cold water, oxygen is less, the activity of the beetle decreases, as respiration slows down.

Therefore, the swimmer prefers to live in small reservoirs with well-heated water.

Diving beetles prefer life in warm shallow ponds.

In winter, there is very little oxygen in the water, often the gas is spent on the processes of decay of organic residues. In this case, the beetle sinks to the bottom and falls asleep until spring. On sunny days, when the ice is still thin and the sun’s rays penetrate into the reservoir, plants continue photosynthesis, oxygen stores increase. The swimmer rises and crawls along the ice crust, consuming oxygen.

The beetle is a real predator. He catches snails, tadpoles, insects and their larvae, fish fry. It can attack larger organisms: newts and frogs. If there are too many swimmers in the pond, they can destroy all the fish.

The larva of a swimmer is more ferocious and dangerous.

They also eat caviar deposited in shallow water and quickly deal with fish fry. The swimmer is a real glutton among insects. The excess of food eaten often prevents him from rising to the surface of the water, then he exerts a lot of effort, rowing his legs, but he cannot get out upstairs. Then the beetle burps excess food from a crowded goiter and empties the back gut to make the body weight less. Sometimes it simply crawls to the surface of aquatic plants.

Well-developed flair and excellent vision allow the bug to hunt for small animals.

A drop of blood that has got into a pond is felt at a distance and rushes to the place of the intended prey. Swimmers can attack with a whole flock.

The body of the bugs-bugs has an elongated shape, allowing easy movement in the water.

If a bite gets at least one drop of blood from the body of the fish into the water, predators immediately come, attracted by the smell. Hungry swimmers pounce on the fish, clinging to the body, they do not leave their prey alone.

The larva of a swimmer corresponds to adult insects in its predatory habits. She has a slender worm-shaped body and huge jaws. The larva swims quickly, rowing in the water with its feet and bending the whole body. Breathes atmospheric air, putting the end of the abdomen to the surface, while waiting for prey.

The development and transformation of her lasts 2-3 months. She is very voracious, eating about 50 tadpoles in one day. The most noticeable sign of her is the powerful sickle-shaped jaw. She plunges them into the body of her victim and pierces through and through. Antennae, palps, simple eyes are located on the head of the larva, but the mouth is absent.

Adult swimming beetles harm fisheries by destroying fish fry.

How does food enter the body? Near the base of each jaw is one hole that opens into the oral cavity. The larva cannot chew and bite. Her food is digested outside the body before it enters the oral cavity.

When the victim bends on the jaws, the larva burps the digestive fluid from the esophagus, it moves along the channel to the end of the jaw and enters the body of the tadpole.

Extraction is paralyzed, then we follow the second portion of digestive juice, it liquefies and digests food. The larva only needs to absorb the nutrient contents. The pharynx works like a pump at this time, absorbing liquid food. When the nutritional process is legal, the larva cleans the crescent jaw of the remains with its feet. But satiation does not occur, always a hungry predator goes in search of the next tadpole.

Adult swimming beetles harm fisheries by destroying fish fry. In nature, they, like all predators, are regulators of the numbers of other animals.

Sea beetle beetle — a perfect predator of water

This insect is carnivorous and belongs to the beetle family. The beetle beetle quickly adapts to natural conditions, so it is not difficult to meet it in the waters of Eurasia. In addition, it inhabits the waters of North America, and also occurs in areas of the Antarctic.

For its vital activity, the beetle chooses reservoirs with stagnant water, which are rich in flora and fauna. The diet of the beetle beetle includes objects of animal origin. He can even live in an aquarium if he is provided with all the necessary conditions and an adequate amount of food.

What feeds on

The water beetle is a predator, therefore its diet consists solely of animal food, such as small fish, all kinds of insects, tadpoles, mosquito larvae, as well as dead fragments of underwater inhabitants.

The beetle is capable of attacking a living object that is larger than the beetle itself. It is enough for him to injure his victim, so that his relatives joined the attack. As droplets of blood begin to stand out from the wound, this starts attracting other predators.

Interesting to know! If you keep a beetle beetle in an aquarium, then you should offer him pieces of fish or pieces of meat as food. This predator should not be placed in an aquarium with ornamental fish, as it will begin to hunt them.

Insect lifestyle

Despite the fact that the beetle can fly, it practically does not leave the reservoir, if there is enough food for it. However, he often rises to the surface of the water to stock up on oxygen. To do this, the beetle has a special place that is filled with air, it is enough for him to expose the back of the body from the water.

In the winter, especially in conditions of extreme cold. The beetle beetle does not show any activity while in a state of anabiosis. To do this, insects in the ground dig special holes, where they wait out the cold.


With the arrival of spring, when it is warm outside and the temperature of the water rises appreciably, the beetle beetles begin to mate. The process is so serious that many females do not survive. Besides the fact that males especially do not stand on ceremony with females, attack them and hold them for a long time under water, which leads to the fact that females do not have the opportunity to rise to the surface and breathe air, there can be several males, and this is certain death. If the female mates with one male, then death from lack of oxygen may not threaten her.

Those females for whom the mating process was successful, after a while begin to lay eggs. At one time, she can lay up to hundreds of eggs, and over the season this bill goes up by thousands. The future of the offspring of the female securely fastens to the stems of underwater plants, due to the special secret that it allocates. After some time, rather voracious larvae appear from the eggs, which immediately begin to hunt the living creatures in the water. At the same time, at the first stages she copes with absolutely tiny living creatures, and after a while she already catches small fish.

How the larva develops

The larvae of the beetle beetle have rather powerful jaws, like the most adult beetle, which allows it to cope with any prey. It literally launches the jaws in the body of its victim and simultaneously secretes gastric juice, which leads to the softening of the victim’s flesh. After the victim’s insides become liquid, the larva sucks in nutrients through two channels located on both sides of the jaw.

After two molts, the insect moves to land, where in a humid environment, usually in the ground, the larva pupates and remains in this state for up to a month, depending on weather conditions. At the end of this time, an adult swimming beetle emerges from the pupa, which is still in its shelter for a week, waiting for its body to grow stronger. After that, the adult sea beetle beetle leaves its shelter and heads towards the reservoir, where it will live for about one year.

Natural enemies of beetle beetle

This insect causes significant damage to fish farms, especially at the initial stage of fish farming, when the beetle can hunt small fish. After the life of this seemingly very small predator, fish farms are not counted a large number of young fish. It should be noted that there are enemies of the swimming beetle, which regulate its numbers in water bodies. Otherwise, serious measures would have to be taken to combat this natural pest of water bodies. Larger predatory fish species, many birds, including gulls, as well as mammals inhabiting water bodies, hunt the beetle beetle.

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Interesting fact! In case of danger, the water beetle allocates a special secret, which with its fragrance scares off those who are not against eating this predator.

Some living creatures are interested not only in the adult beetle, but also in its larva. It is worth paying attention to the special natural enemy of the larvae of the water beetle beetle — this is an insect rider. The peculiarity lies in the fact that the female rider, having found the eggs of the swimmer, lays in them his eggs, which are developed at the expense of the nutrient medium of the eggs of the beetle. After the rider larva eats all stocks, it pupates. After some time, an adult insect, a horseman, emerges from the egg of a swimming beetle.

Therefore, in spite of the high fecundity of this predator, its populations in water bodies are maintained at an optimal level due to natural enemies, which makes it impossible for it to exert a serious influence on the populations of various fish species.


Despite the relatively small size, the beetle beetle is able to cope with prey, which is much larger in size than the beetle itself. If he himself cannot defeat his victim, then his relatives will help him in this, it suffices to leave small wounds on the victim’s body. In other words, although the bug is small, the damage from it can be enormous.

Morphological description

Divers (Dytiscidae) are a family of medium and large beetles living in water bodies. They are found throughout Europe and Asia, and even Arctic territory was settled in North America. Insects choose fresh water with lots of plants and stagnant water. These can be ponds, lakes, ditches and deep pools. The size of the beetle beetle, depending on the species, is 2-4.5 cm.

A universal insect can crawl, swim and fly. Not many representatives of the order of beetles are endowed with such abilities. On land, swimmers move slowly, waddling from side to side. The hind limbs are repelled, and the front and middle enumerated.

Description of the beetle beetle

The oval, flat, streamlined body of the beetle is optimally adapted for movement in the water column. The hind legs act as a mechanism providing movement. The limbs have well developed muscles. The flattened lower leg and foot are covered with two rows of elastic hairs. The method of movement of the swimming beetle in the water resembles rowing with oars. Hind limbs move simultaneously. Durable bristles on their surface replace the propeller blades. Middle legs regulate the direction of movement — up or down. The front limbs are not involved. The front and middle legs are noticeably shorter than the rear.

The body consists of three sections: head, chest, abdomen. The head is fixed on the chest, which, without a sharp border, passes into the abdomen. The color is mostly dark — green, brown, black. In some species, a light (gray or orange) edging runs along the body and head. The abdomen consists of 8 segments, covered with rigid elytra.

Swimming beetle

The head of the insect is wide and flat. On the sides are large eyes. Each consists of 9 thousand simple eyes, allowing you to distinguish between static and moving objects. Behind the transverse plate of the upper lip there is a powerful jaw designed to grip and chew prey. Mouth apparatus of the gnawing type. Long segmented antennae are the organ of smell. They are located on the sides of the forehead, consist of 11 bare segments.

How a sea beetle breathes

The swimmers spend most of their lives underwater, but breathe air. Insects need to regularly surface to replenish their oxygen stores. How does the swimming beetle’s respiratory system? Air intake in the body is provided by special holes — spiracles, located on the abdomen. From the respirator to all parts of the body, the tracheal system of tubules diverges. There are air sacs in the insect’s chest. The abdomen rhythmically compressed and expanded, creating air movement in the trachea.

On the body of the beetle there are glands that lubricate the ends of the elytra and abdomen. For the renewal of the air reserve, the fish places the end of the abdomen out. The contractions of the organ allow air to be forced under the sheaths. The larvae also breathe, their torso ends with filamentous appendages that function as spiracles. To inhale a portion of air, an insect pops up every 10 minutes.

Beetle formed an air bubble

Power Features

What does a swimming beetle eat? The predator consumes any protein food, it does not hesitate to eat dead fish. Sharp and wide mandibles allow you to attack large prey. A hungry beetle attacks fish or frogs 3 times its size. How does he cope with large prey?

Beetles are bloodthirsty predators

He is helped by the rest of the swimmers living in the reservoir. After the first bite, the victim’s blood enters the water. Due to the subtle sense of smell, predators catch it at a considerable distance. A dozen beetles are gathering around the fish, which tear off pieces from live prey. In most cases, insects are content with invertebrates and mollusks.

The development of the larvae

The color of the larva of the beetle beetle is yellow, gray, brown. Often the body is covered with a pattern of dark stripes and spots. Externally, the offspring is similar to scorpions, and not to swimmers. From birth, larvae are voracious predators. The first food is caviar, larvae of caddisflies, dragonflies, mosquitoes. The head is flattened, the chest consists of three segments, the belly of eight segments. On the sides of the head are located on 6 simple eyes. The antennas are thin, at the first age 3-segmented, after two molts — 6-segmented.


Oral appendages are located transversely. There is no upper lip, and the lower lip is formed by a wide plate with palpi at the edges. Durable mandibles are curved in the shape of a sickle, the edges are pointed. They only move in a horizontal plane. Mandibles channels connected with the pharynx. The larvae have no oral opening. Food enters through the jaws.

The digestive system of insects is also unusual. Extraction is not fermented into the stomachs, but outside. The larva immerses its mandibles into the body of the victim and injects digestive juice. After a few minutes, the tissues and organs soften. The contents of the prey are absorbed directly into the pharynx. After finishing the diet, the insect cleans the mandibles with its front paws. The larva of the swimming beetle is a tireless and voracious predator, having finished with one victim, she sets off in search of the next.

The oblong broad body narrows to the rear end, surmounted by two cerks. There are various formations on it: spines, setae, scales. Three pairs of long limbs attached to the thoracic segments. Legs consist of 5 segments. On the thighs and shins swimming hairs, foot ends in two claws.

The larva shows the makings of a predator

In its development the larva replaces 3 instars. The longest is the last third age. In early autumn, the larva leaves the reservoir. On the shore, she builds a cradle of the remains of plants and soil lumps. Pupation occurs in the crib. Phase lasts about a month. Pupa white, soft, open type. The imago after appearing from the pupa is also soft and light. After a few hours, their cover darkens and hardens.

Baby dolly

Bordered Float

A common species of beetle beetles, whose habitats are bodies of water with standing or low-current water. Oval torso black or dark brown. The limbs are orange, as is the edging running along the sheaths. The size of the imago is 27-35 mm; in the Far East, a larger subspecies is found (32-37 mm). The male is smaller than the female and is distinguished by the smooth surface of the elytra. Carnivorous predators attack the larvae, fry, tadpoles, in the absence of small prey — frogs and fish. They live in Europe, Central Asia and Siberia.

Bordered Float

Wide water fin

The length of the body of an adult beetle is 35-45 mm. The large wide beetle is different brown or black with a green tint color. The photo shows that a yellow border runs along the edge of the pronotum and elytra of the swimming beetle. The larvae have a long spindle-shaped body, they are larger in size than adults, growing to 60-60 mm. Insects inhabit lakes with clear and muddy water. Prefer to keep close to shore. Observed in reservoirs overgrown with sedge, horsetail, sabelnikom, water lily. A wide water finder is a rare species. He disappeared 10 European countries. The beetle is listed in the IUCN Red Book.

Information. In water, swimmers have few enemies, large predators do not touch them. Insects have a protective mechanism — when attacking an enemy, they emit a white, caustic liquid.

Wide water fin

Unwanted neighborhood

Settling in a decorative pond, the predatory beetle attacks ornamental fish and other inhabitants. Owners of reservoirs are faced with a difficult problem, how to get rid of the beetle beetle in a pond? The least laborious way is to get crucians, which actively destroy the larvae of the swimmmer. Another option is to temporarily install a pump or fountain that creates a movement of water mass. The insect prefers stagnant bodies of water, so it leaves the shelter and sets off to find a better habitat.

If the listed methods did not work, then it remains to drain the water, to clean and disinfect the bottom. This will destroy the imago and beetle larvae. After treatment, water is poured and new inhabitants are launched.

Danger to humans

You can encounter a predatory beetle swimming in a lake or in your own pool. Insect aggression to humans is extremely rare. The bite is painful, but does not pose a threat to health. A water beetle bites in water if it feels threatened. Pain from the puncture of the skin remains a few minutes. After some time, the wound swells, a lump may form. Beetles are not poisonous, so there is no allergic reaction.

The victim must be given first aid:

  • wash the wound,
  • treat with an antiseptic (iodine, hydrogen peroxide),
  • bandage,
  • apply ice to relieve swelling.

Attention. Often the bite of a swimming beetle is received by those who take it in their hands without the necessary skill.

Home maintenance

Lovers of aquatic fauna may contain a swimming beetle in an aquarium. As food, he is given pieces of raw meat and fish. Capacity cover with a lid, otherwise the winged beetle will fly away. Sand is poured at the bottom and coarse pebbles are laid. Algae choose any, swimmers do not eat them. The main thing is that it is impossible to place beetles in one aquarium with fish.

Beetle — description, description, structure, photo. What do beetles look like?

A characteristic feature of beetles, or beetles, is the presence of solid chitinous or leathery elytra, formed from the upper pair of wings. This kind of armor protects the folded flying wings of an insect from damage in those moments when it is not in the air.

The body shape of the beetles depends on the habitat and species. In aquatic inhabitants, it is slightly flattened, streamlined and compact (swimmers, wizards).

For beetles living in the soil, a slightly convex body shape with a powerful, widened front part (scarabs, dung beetles) is characteristic.

The beetles living on the surface of the earth have a strongly convex upper part and rather long limbs (ground beetles).

In the structure of the body of adults there are three main sections: the head, chest and abdomen.

The head of the beetle is round, slightly flattened shape, although in some families it has the form of an elongated tube. It can go deep into the prothorax and be practically invisible or connect with it freely with the help of a moving neck. In some beetles, the head is a constrictor, at the end of which there is an oral apparatus (weevils, pseudo-slopes, trubkovertov).

The head of a beetle can be:

  1. Prognathic (mouthparts and antennae are directed forward),
  2. Orthognathic (hypognathic) (mouthparts directed downward),
  3. Opistognathic (mouthparts directed back).

On the upper surface of the head are placed different lengths of the antenna of the beetle, consisting of separate segments that perform the functions of the olfactory organs.

The mustache of the fan beetle Rhipicera femorata look like long eyelashes

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On the sides are well-developed, complex faceted eyes of the beetle, sometimes consisting of 25 thousand individual lenses that create a mosaic image.

In some species on the crown there are additional simple eyes, while in the underground and cave dwellers the organs of vision may be completely absent.

Ротовой аппарат большинства жуков, предназначенный для измельчения пищи, состоит из парных мандибул (верхних челюстей) и максилл (нижних челюстей). На нижней губе и челюстях жесткокрылых располагаются небольшие щупики, являющиеся своеобразными органами осязания и вкуса насекомого.

Самые большие мандибулы наблюдаются у жуков рогачей (у жука-оленя и жука-геркулеса).

In the structure of the breast of beetles, three segments are distinguished: the prothorax, movably connected with the mid-chest and accreted with the labia. From the side of the back, the segments are called pronotum, mesonotum, and metanotum. Each segment is formed by two half rings (upper tergite and lower sternite), which are movably interconnected. Hard elytra are attached to tergites of midspice, and webbed wings are placed on beetle on dorsal beetle. Three nursing sternites carry over a pair of limbs.

The form and sculpture of pronotum is very diverse, and its structure plays an important role in the classification of beetles. It can be either smooth or with lateral spikes or various forms of growths.

Extremities of beetles consist of 5 parts: a basin, a swivel, a thigh, a shin and a foot.

A distinctive feature of beetles is the presence of special spurs on the top of the shin, which can be paired or single. The legs of the beetle are covered with small dense hairs and have two claws of different shapes and lengths each.

Depending on the lifestyle of the beetle (beetle), the appearance of the limbs may differ somewhat and perform running, grasping, digging, swimming, or jumping functions.

In the process of evolution, the front wings of beetles turned into rigid elytra, not inferior in hardness to the insect’s chitinous exoskeleton.

In the folded state, the beetles of the beetle serve as a reliable protection for the mesonotum, the labia and the upper abdomen.

In species with reduced lower wings, the elytra usually coalesce, forming a monolithic skeleton. Some bark beetles have a dimple on the surface of the elytra, which is intended for transporting wood waste formed during the gnawing of a system of passages in the body of a tree.

The surface of the elytra is smooth, covered with a variety of grooves, outgrowths, grooves and spikes.

Sea beetle beetles with grooves

Elytra with depressions in the beetle Stigmodera macularia

The lower webbed wings of beetles are usually transparent and may be slightly colored or completely colorless.

Depending on the species and species, veins may have a different texture, both with the formation of transverse cells and with medial veins and branches from them.

The color of beetles is often a characteristic by which insects are divided into separate species.

The color of the beetle is usually monochromatic, dark brown, red-brown, black, green, yellow or red, often with a metallic tinge. However, there are species with characteristic bright patterns on the surface of the body or with a bioluminescent glow.

Goliathus regius beetle goliath

Stag beetle Phalacrognathus muelleri

Sexual dimorphism of beetles is usually expressed in size and color of individuals of the opposite sex.

In most species, males of beetles are smaller than females and have a more elongated body. However, in some genera, due to excessively developed mandibles resembling horns, the size of the beetles of males is much larger than the female. Also the length of the antennae or the front legs can indicate the belonging to a particular gender.

Elephant beetle, or megasoma elephant, — female on the left, male on the right

For some species of beetles, sound intercourse is characteristic, allowing to maintain relationships within one population, and males to find females and scare away insects of another species. Sound vibrations occur due to friction of the prothorax on the midgut.

The size of the beetles that make up the beetle varies in a wide range. Among these insects there are both real giants and babies, which can be well examined only under a microscope. For example, the size of a woodcutter-titanium beetle (Lat. Titanus giganteus) can reach 22 cm in length, relic woodcutter (lat. Callipogon relictus), living on the territory of Russia — 11 cm, and the length of the baby Scydosellamusawasensis does not exceed 352 microns.

Beetle woodcutter-titanium (lat. Titanus giganteus)

Relic woodcutter (relic barbel) (Latin Callipogon relictus)

Little Scydosella musawasensis beetle under the microscope

Where do bugs live?

Beetles live in almost all corners of the globe, ranging from the sultry deserts and humid equatorial forests, to the endless expanses of the tundra, with the exception of the eternal snow zone of high-mountain peaks, as well as the ice fields of Antarctica and the Arctic.

The numerous group of beetles includes species of beetles that live in the near-surface fertile soil layer, inhabit the bark, wood or tree roots, as well as flowers or leaf cover.

The inhabitants of the desert and semi-desert adapted to the conditions of high temperatures, so they are active nocturnal. Many beetles inhabit fresh or low-salt water bodies with abundant coastal and bottom vegetation.

What do bugs eat?

Among the insects included in the order Coleoptera, there are representatives of almost all known types of food inherent in arthropods. There are predator beetles that feed on other insects and their larvae, herbivorous beetles that feed on mushrooms, foliage, roots, fruits and seeds, as well as beetles that eat wood or bark of various plants. Many beetles are pests of crops and eat the leaves of potatoes, beets, cabbage, pears, apples, and other vegetables, fruits and fruit trees. One of the most famous pests is the Colorado potato beetle, which feeds on the leaves of solanaceous crops.

There are even species that are, in essence, forest nurses, as these beetles feed on dry and decaying parts of plants or decaying animal remains.

In addition, the food of beetles depends on the stage of development of the insect.

Imago of some species that feed on wood, pulp of green shoots, pollen or juice, being larvae at one time, ate decaying organic remains, or were predators. There are families that accumulate in the larval stage an adequate supply of nutrients, allowing adults to do without food for the rest of their lives.

The beetles, through their vital activity, have a positive effect on the ecosystem in their habitats. Both adult beetles and their larvae process dried wood, as well as plant parts affected by various fungal diseases, actively participating in the process of humus formation. In addition, beetles can act as pollinators of flowering plants.

At the same time, some species of beetles can cause significant damage to most crops and forest plantations, the leather and tobacco industries, museums and libraries, as well as wooden structures and furniture.

Types of beetles, photos and names

The beetle detachment is one of the largest groups living on the planet today. It consists of about 390 thousand species of beetles, most of which have been little studied, since their description was compiled from single specimens found in a separate area.

Among the variety of families that make up the beetle, the most famous are the following:

  • Ground beetles (lat. Carabidae), including about 30 thousand species.

The length of the body of beetles from this family varies from 1 mm to 10 cm. The body is painted in dark colors, often with a rainbow shade, usually elongated and oval, although there are varieties that resemble a biconvex lens or a plant leaf. In the form of food, the species of beetles in the family can be both predators and herbivorous.

One of the representatives of this family is ground beetle, or hunchbacked pawn (lat. Zabrusgibbus,Zabrustenebrioides)having an oval-shaped body. The color of the beetle is saturated black with a metallic tinge. The size of an adult ground beetle can reach 12-18 mm. Well-developed mandibles enable the ground beetle to easily cope with hard plant covers in search of food. Slender insect legs are adapted for a quick run. Large elytra almost completely protect the abdomen.

This beetle lives in areas with moderate air temperature and high humidity, so it can be found in Egypt, Morocco, Tunisia and other countries in North Africa, in Italy, Spain, France, on the European territory of Russia, in the United Kingdom and Sweden. The largest populations of this species are found in Moldova and Ukraine.

  • Weevils or elephants (lat. Curculionidae), numbering in its ranks about 60 thousand species of beetles.

A distinctive feature of the representatives of this family is the special shape of the front of the head, resembling a tube. The size of adults, depending on the habitat can reach 30-50 mm. This family is characterized by a large variety of body shapes, which can be practically cylindrical, pear-shaped, rhombic, hemispherical, or flattened. The color of the beetles can be yellow, brown or black, sometimes with spots of a lighter or darker tone. All beetles in the family feed on plant food.

A typical representative of the family is rice weevil (lat. Sitophilus oryzae), having an elongated, slightly convex body up to 2.5-3.5 mm long with a thin elongated rostrum. Matt or slightly shiny chitinous covers of the beetle are colored brown. The surface of the pronotum is covered with rather large pits. Elytra traced by frequent thin grooves, between which are visible small points that make up the short rows.

The rice weevil beetle lives almost throughout Europe, Asia, Australia, the North and South Americas, as well as in Africa.

  • Beetles predators (lat. Staphylinidae), including almost 48 thousand species.

A characteristic feature of the beetles belonging to this family is the presence of short elytra. The size of beetles vary in the range of 0.5-50 mm, but the body length of most species does not exceed 8 mm. The outer covers are colored red-brown or brownish-black, often with spots of an indefinite form of red or yellow. These beetles live on almost all continents. Predatory insects inhabit the territory of the Czech Republic, Canada and Alaska, Japan, Europe, China, and North America. According to the method of feeding within the family, not only predators or scavengers are emitted, but also species whose diet consists of decaying plant debris or pollen, algae and plant sap.

One of the brightest representatives of the family can be considered coastal stafilina (shoreline blue-winged) (lat. Paederus riparius).The imago of this species grows up to 10 mm in length. The elongated spindle-shaped body of an adult beetle is yellow-orange or red, except for the blue elytra, as well as the head and the styloid end of the abdomen, which are painted black.

The beetle lives practically throughout the whole territory of Eurasia, North and South America, North Africa and Australia. It prefers to settle near water bodies or in damp grassy litter on household plots, where it destroys agricultural pests.

  • Lamellar (lat. Scarabaeidae), which include about 28 thousand species of beetles.

Numerous members of this family are characterized by average sizes ranging from 2 to 60 mm, although larger bugs are also found. The body of individuals of most species is oval, but there are subfamilies with an almost square or cylindrical shape. The color of the chitinous integuments is dark green or dark brown, and their surface can be covered with all kinds of growths and spikes. Most species of the family feed on manure or rotting plant remains.

The beetle is considered to be the most famous member of the family holy scarab (lat. Scarabaeus sacer). These beetles have a smooth strongly convex rounded-oval body, painted black, the length of the beetle is up to 25-37 mm. A distinctive feature of the scarab is the presence of large teeth on the surface of the shin of the front legs.

The spread of the beetle seizes part of the countries of North Africa, Spain and western Georgia, Yugoslavia, Bulgaria, Cyprus, Ukraine and Sicily. Individuals of this species of beetles feed not only on plant food, but also on animal manure.

  • Leaf beetles (lat. Chrysomelidae)

The structure of this family includes more than 36 thousand species. The body shape of leaf beetles can be both oval-flattened and strongly spherical, and the color of beetles is bright green, greenish-blue, bronze-yellow, etc. The size of an adult insect rarely exceeds 15 mm.

One of the most famous members of this family is leaf beetle green mint (lat. Chrysolina herbacea). It is a rather small insect, with a smooth convex body, which is painted in a bright blue-green color with a clear golden tint. Adult sizes rarely reach 11 mm. The food of the beetle is the tender leaves of a fragrant mint plant that gave the name to the species.

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  • Usachi, or woodcutters(lat. Cerambycidae), numbering about 26 thousand species in their ranks.

A distinctive feature of beetles from the family of mustaches are long whiskers, which can exceed the length of the body of an insect several times.

The big oak barbel is a beetle with a very long mustache. The whiskers of this beetle are 2 times longer than the insect itself!

Depending on the species, the shape and length of the beetle’s body, as well as the sculptural decoration of the elytra and pronotum are different. Despite the fact that most species in the family are of medium size, there are giants among them, one of which is the beetle titan woodcutter (Titanus giganteus). It is the largest beetle in the world. Its maximum size can reach 22 centimeters in length, and the weight of the beetle exceeds 25 grams.

The body of the insect is elongated, slightly flattened, when viewed from the side it resembles a lens. Color brownish brown or tar-black. The pronotum clearly shows three sharp spines located on each side. Life expectancy of males does not exceed 35-38 days. The largest beetle in the world is a titan woodcutter living in the countries of South America.

Water Beetle: Description

One of the most widespread representatives of the family of swimmers of the order Coleoptera, the suborder of carnivores, is the fringed finder. It is found in Western Europe, right up to Asia. The name of the family in Greek means “diving”. All species have a similar life cycle. Female beetles lay their eggs in the stems of plants (only under water). The larvae that hatch from them grow rapidly and as a result turn into terrible hunters on the inhabitants of the reservoir. They are even called water tigers. As a rule, the size of the larvae is much larger than the adult beetle. In just a couple of weeks, the water «tiger» will become the highest predator in the pond. The length of the beetle can reach 37 millimeters.

Types of swimming beetles

Other members of this family include the striated swimmer — it is a dark-brown insect and has yellowish spots on its abdomen. The smallest divers are considered — their length does not exceed 5 millimeters. It is also worth mentioning the black-strip dive living in North America and Europe, and the beautiful diving — this small pale yellow bug lives in southern Europe, preferring salty water bodies.

In the populations of swimming beetles, there are several forms of females: some with uneven covers, others with a distinctive paw structure. Due to this, organisms of the same species that live in the same territory for a long time and survive. The fact is that females with uneven covers are more likely to survive after repeated matings, but for women with a smooth form, the probability of fertilization is higher.

The population maintains a certain balance between the females. The proportion of representatives of smooth forms decreases with increasing suckers on the paws of males. At the same time, a strange tendency was noticed: in populations living a little to the north, there are strongly developed suckers, respectively, smooth females are much smaller.


A swimming beetle lives in standing ponds, choosing deeper, well overgrown reservoirs with a rich wildlife. He needs a «house» that will provide a good supply of food, because these insects are predators by the way of feeding.

However, the swimming beetle (the habitat in nature is described above) also feels great in an aquarium, attracting the attention of even those who are not keen on aquarism.

Body parts

The body of the swimmer consists of three sections. This is the head, chest and abdomen. All departments are still articulate with each other. All this in combination with the oval shape of the body contributes to the fact that the beetle swims perfectly. The head of the swimmer is pushed into the chest, the thoracic segments are fused, smoothly passing into the abdomen.

On the head there are mouthparts and sense organs. The water beetle is an active predator. Due to the fact that the mouthpieces are directed forward, the insect can grab prey while chasing. The upper lip has the form of a transverse plate. Behind it is a pair of remarkably developed jaws, which seize and crush the victim. Their ends are pulled forward like pointed teeth. Behind the upper jaws there is a pair of lower ones with palpi, they are bounded on the sides by the mouth opening. Below the mouth is the lower lip. Short palpi on the jaw and lip are the organs of taste and touch.

With the help of mouthparts, finders and some other insects seize, gnaw, and grind prey. Therefore, they are called gnawing.

По бокам на голове находятся сложные глаза. Каждый состоит из 9 тысяч простых глазков. Жук-плавунец окаймленный, форма тела которого по обтекаемости и прочности сравнивается с подводной лодкой, различает очертания и величину двигающихся предметов. Впереди глаз у насекомого имеется пара усиков, которые относятся к органам осязания, обоняния и вкуса.

Ноги и крылья расположены на члениках груди. On the back of the beetle, only the first segment can be seen. Its upper part — the so-called dorsal shield — is shaped like a trapeze. The remaining segments of the breast, however, as well as the abdomen, are covered with rigid sheaths (modified front wings), which are protected from above by delicate rear wings. The remaining parts of the body of the beetle-beetle hide in solid covers.

Hard front fenders are characteristic of all beetles, which is why they are called beetles. First, the finder lifts, deflecting a little to the sides, elytra, then straightens the folded wings and only after that flies up. In flight, the elytra and wings for the insect are as important as the bearing surfaces and the propeller for the aircraft. On land, the swimming beetle moves rather slowly, while rolling over from side to side, pushing with its hind legs and turning over with its front legs.

Despite the fact that swimmers live in water, they have no gills, but they breathe atmospheric air. Floating to the surface of the reservoir, the beetle exposes the posterior end of the abdomen from the water, thus gathering air into the cavity. Spiracles, where oxygen enters, are located on the edges of the abdomen. In winter, when ice forms on the surface of a pond, the swimmer uses bubbles emitted by aquatic plants. Another option is also possible: a beetle blows air out from under the elytra, and after a while it retracts it back. While the bubble is in water, it is saturated with oxygen dissolved in it. This is how a floating fish breathes only at low temperatures (at this time it is not very mobile, therefore, the air consumption is very small).

Due to the ability to regulate the amount of oxygen under the elytra, insects can float near the surface of the water or descend to great depths.

A swimming beetle is a predator in its feeding method, it is able to attack a prey whose dimensions are several times larger than its own. As a rule, it feeds on various aquatic invertebrates, sometimes fry, and it can also eat ten centimeter fish and even newts. Large inhabitants of the reservoir slam the beetle with sharp movements, but blood starts to ooze from the wound that he has inflicted, and then the rest of the swimmers attack the prey. The fate of the victim is predetermined if there is more than one swimming beetle in the pond. What this predator eats, we already know, but here you can also add dead fish and frogs, which were in the water.

Safety devices

To consider the structure of the beetle-beetle, take it in hand. When lightly compressed, a whitish liquid with caustic properties will begin to protrude from under the chest shield. For this reason, large fish and aquatic predators do not hunt for swimmers.

The protective device of an insect can be considered its color, which imitates well the dark background of the surface of a non-flowing reservoir. When the swimmer rises to the top, he puts the back end of the body out of the water, however, thanks to the color, waterfowl hardly notice it.

Mating season

The mating of swimmers begins immediately after hibernation. Taking off from their underground bedrooms, the beetles go in search of a suitable reservoir, relying only on their vision. Sometimes they plop heavily on wet asphalt or on the roof of a house. Quite often swimmers go down near the water, and then the rest of the way has to be done on foot. Driving by land is rather awkward.

Egg laying

Immediately after mating has occurred, the female begins to lay eggs. Their length is about 7 millimeters, and the diameter is 1.2 mm. One female lays about 1000 eggs per season, especially prolific — up to 1500. Perhaps this is only with consistent ripening, so the whole process is delayed until the end of June. Eggs are laid in plant tissue. To protect the female, she cuts them with egg-laying, however, this does not always save future offspring from parasites. One of the most dangerous enemies for swimmers is the rider of prestichii. These parasites lay dozens of their own in each beetle egg. The rider’s larva feeds on a floating egg, pupating inside it. Young parasites emerged from the dolls mate, and then leave the shell. Prestistichi and karafrakusy — the only enemies of swimmers.

Dexterous and gluttonous predator

In the larvae of the dipper, external digestion. In its crescent hollow jaws, a channel passes through which digestive juice is injected into the body of the prey. It turns out that he is able to dissolve the tissues of the victim, turning them into broth, which the larva feeds through the same channel in the jaws. The bite of this small and voracious predator is very painful.

In length, the larva of a swimming beetle bordered reaches 6 centimeters, 1 cm wide. It breathes, like an adult insect, with atmospheric air, barely exposing the tip of its abdomen out of the water. The life of the larva is from two to three months, during this period of time it sheds once.

Pupation occurs on land. First, the larva makes an earthen cradle. A week later, it begins to pupate, and after another 14-21 days the pupa turns into a beetle. Initially it is white in color, with very delicate covers, black eyes and brown legs. Over time, the integuments will become rigid, and the beetle will acquire a familiar look.

The larvae of the finned fish inhabit, like adults, in fish breeding ponds. They can do serious harm because they eat fish fry.

Content in an aquarium

To keep a swimming beetle at home, you need to equip it for housing. The aquarium in which the insect will live should be spacious, about 60 centimeters in height. A swimming beetle is considered one of the largest on Earth (among aquatic invertebrate arthropods).

It is imperative to install a filter in the aquarium, and one that is not designed for air supply is also suitable. A swimming beetle (which a predator eats, we have already figured out) will not die from lack of oxygen, because at any moment it can float to the surface and replenish the air supply.

Keep this insect is desirable in a closed aquarium, because it flies remarkably. Once again, I would like to note that you should not keep a swimming beetle with fish, because you decided to acquire a predator.

Interesting Facts

It turns out that the larva of the swimming beetle is considered the most bloodthirsty in the world, despite the fact that it has no mouth. On her head there are protruding forceps, which are equipped with double tubes, and a poisonous compound is sprayed into the victim’s tissue through them. With the help of the same channel, the contents of the prey body are also sucked out.

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