Sworden beetle (lat. Dytiscus). The scientific name comes from another Greek word, which in Russian means “capable of diving”. This type of insect belongs to the brutal detachment, the family of the floodplains.
Description
Poduns belong to carnivorous beetles. They are widespread among individuals living in water. There are about 4,000 species around the world, and only 300 in Eurasia. Slavunta beetles prefer reservoirs as a habitat without a strong course, lakes, swamps, ponds, etc.D. Also, insects were able to cross the air and land without any obstacles, but they feel much better in water. There they spend most of their lives.
Appearance
The size of the beetle of the beetle depends on what kind they belong to. For example, a bordered flood has a 27–35 mm, dives up to 5 millimeters, a variegated dive is changed from 2.7 to 3.7 mm. Basically, the size of small individuals does not exceed 4 mm, and adults 5 cm.
The body of the floodplains has an oval, expanded on the back of a flat shape. The form depends on the type to which the individual belongs. For example, in some peaks, the overlap is pointed, although in others they stretch into the shape of a spike.
The coloring can be different. Pretty more often one-color: brown, light brown, black. Often some pattern is depicted on the body.
The hind limbs of beetles are well developed, covered with elastic hairs, as well as flattened legs. This suggests that the floods are adapted to movement in water. The front and middle limbs are shorter than the rear. Especially the front ones.
The surface of the body is very rare when it is smooth. Mostly rough. Some species have hairs.
The body itself is divided into three parts: head, chest, abdomen. The head is very small, wide and motionless, passes to the abdomen. Big eyes are located on the sides of the head. They are divided into two forms: transverse and rounded. One eye is 9,000 eyes. Antennae are located on the sides of the forehead. The mouth was built as follows: the upper lip is crossed, in the middle of the front edge with a recess, rarely straight. The jaw is located behind the upper lip. Mandibules are short and strong, hidden under the upper lip. The oral apparatus itself is designed to capture production.
Except for the head, then the body can still be divided into:
The wings of beetles are well developed. Odlallya closes the whole abdomen.
Kinds
More than 4,000 species of floating beetles are found in the world.
Lifestyle and behavior
Basically, swimming beetles are engaged in hunting or rest. The swimmer without effort pops up to the surface of the water. His body is much lighter than water. To stay at the bottom of the reservoir, he needs to catch on a plant or stone. Pudsers are often active at night. In this night gap, they go hunting or searching for a new house. They spend winter time in the egg or larvae phase. But those who live in Europe plunge into a range. After appearing in the fall from the doll, the young beetle remains to winter in the litter or under the bark. And the complete freezing of the reservoir or lake makes bugs fall asleep to warming.
Before flight, the beetle is selected ashore and empties the contents of the intestine. Then he, as reducing the weight of the body as much as possible, fills the air tracheal bags on his chest and takes off. Poduns mainly focus on the brilliance of reservoirs. Noticing it, they are reduced.
Slavynets live for no more than one year, and the Imago is no more than four.
Protection
If you catch a floodplain, take it in your hands and squeeze it slightly, then a white liquid will perform from under the chest shield of the beetle, which has very caustic properties. Thanks to this, the beetle is not touched by large fish and other water predators. In addition, the color of the beetle also plays a role that imitates the dark background of the surface of the standing reservoir. When the beetle hangs in water at its very surface, exposing the back of its body from the water, its color makes it almost invisible to waterfowl.
Where it lives
Individuals live in reservoirs of various types:
Most of the beetles still prefer ponds with standing water. But there are species that prefer water with a quick current. There are also types of floods that are inhabitants of groundwater or wells. Such species have no eyes, wings are rudimentary and there are hairs on the body.
If suddenly a reservoir or puddle dries, then the beetle changes the habitat. He can change it to an artificial one, but if fish is bred in this place, then the beetle can destroy them. In this case, only the complete disinfection of the bottom of the reservoir and rebreeding its inhabitants will help.
What eats
Slavynets beetles are predators. They are actually the most voracious. In addition to fish, beetles eat: gunpoint larvae, bugs, worms, caviar fish, fry, mollusks, tadpoles and others. The method of nutrition of the imago and larvae is diverse: the imago bites and chew their prey, the larvae pierce it with mandibules and suck it, initially letting the secret of the salivary glands into a pierced place, dissolving the insides of the victim.
Reproduction
Males are not characterized by caring for females. They choose a suitable individual and attack it, proceeding to mating. During this entire period, the female can be hidden by several males. The process occurs under water. Some of the males die due to the fact that they could not once again replenish air stocks.
After mating, the females lay eggs in the algae, piercing their egg. The method of laying eggs depends on the structure of the egg. The incubation period lasts differently depending on the type, but mainly about 4 or 15 days. However, the egg phase can last larger. In one season, the female lays more than a thousand eggs. The larva passes 3 stages in development. The most long is the third stage. On it, larvae are actively moving. Breathe either atmospheric air or dissolved in water with the help of the skin. The larva at the third stage, reaches the necessary physiological state and leaves the reservoir. In the coastal zone, it arranges for itself a cradle where it is pushed out. After leaving it, he returns to the reservoir.
Natural enemies
Exclusively vertebrates hunt for smogs: fish, birds and small mammals hunt. But the floodplains are often the owners of parasites.
