Dragonfly flat: features of the appearance and development of insects, factors threatening the population

Flat bellies is one of the genera of the family of real dragonflies. Its representatives are distinguished by a relatively short and highly flattened abdomen. The main species diversity is concentrated in North America, but several interesting groups are present in Europe. The most common is a flat dragonfly, which can be found in the beloved corner of the Old World. Dragonflies have eyes so large that they touch at the top. Larvae develop in clean standing waters.

Morphological description of the species

Dragonfly flat (Libelluma depressa) or squeezed flat belly belongs to the family of real dragonflies, the genus of flat belly. The length of adults is 33-40 mm, wingspan up to 80 mm. A characteristic feature is a very wide and flat abdomen. The most prominent organ of the head is the large eyes. They are so large that they touch in the forehead. A complex organ of vision, consisting of tens of thousands of eyes, allows the dragonfly to evaluate the shape and color of the object. The upper half of the eyes is brown and the lower is yellowish green.

The head is free, it moves perfectly in any direction. The mouth apparatus is gnawing, small strong teeth quickly grind the caught prey. The middle of the lower lip is yellow. Antennae short, composed of 7 segments. The suborder of dragonflies includes fast-flying insects. Their front and rear wings vary in size and shape. In a calm state they are held perpendicular to the body. At the base of the hind pair of wings there is a large triangular spot of brown color, on the front ones smaller.

Interesting fact. Scientist Carl Linney initially included all dragonflies in the genus flat-bellied (true dragonflies).

The color of insects changes with age, moreover, they are characterized by sexual dimorphism. Young males with a tan belly, which is gradually covered with a bluish bloom. Older females are darker than young, their breasts are brown, there are yellow spots on the edges of the brown abdomen.

Distribution area

Europe is the main distribution area of ​​the species. Dragonfly flat lives in the northern countries (Scotland, Sweden, Finland), as well as in the south (Mediterranean. Greece). The species is found in the Middle East, Kazakhstan and Central Asia. In Russia, it lives in European regions, the Caucasus, Siberia, and reaches the Altai Territory. Insects penetrate the western part of China.

Lifestyle & Reproduction

Flat bellies are swift aerial predators, capturing prey with sharp spikes. Small insects are eaten right on the fly. For a more thorough dinner, flat-bellies sit on a twig and eat a butterfly or locust, holding their paws. They are able to make turns, hang in one place, dramatically change the direction of flight. Wings of the wings occur at a tremendous speed - 30 in 1 second. The wings are made of two layers of chitin, have a complex venation.

The insect years begin in May and last until the end of summer. They can be found near quiet ponds and lakes, they do not fly away from water bodies. Moving dragonflies are the first to populate newly created artificial ponds, prefer sunny, well-warmed places.Larvae are able to live only in clean water, so insects settle away from industrial areas. Males are characterized by territorial behavior. They regularly fly along the boundaries of the site, scaring away unsolicited rivals.

The hosts enter into short fights with violators not only of their kind, but also of other dragonflies. Cases have been noted when flat-bellied live in groups of 4-7 pieces. They choose a sunny meadow, where they are sitting on tall plants waiting for prey. The hunting territory is guarded by common efforts. During the breeding season, insects are divided into pairs. courtship flight does not last very long. The female alone is looking for a place to lay eggs. During the ovipositor, she does not dive into the water like some species, but simply dips the tip of the abdomen into the pond.

Information. The female dragonfly flat does not have an ovipositor, so they drop round eggs directly into the water. For the ovipositor, a section of the reservoir with flooded vegetation is selected.

Features of the development of offspring

The incubation time of masonry is 4-5 weeks, in warm water, development is accelerated. Flatbelly chooses ponds and lakes with a muddy or clay bottom for their offspring. Larvae are often covered with bottom sediments that change their color. This is a great disguise for hunting and protection from larger predators. The body of the larva is massive, covered with hairs and bristles. Development takes about two years, 10 links pass. After the fourth, wing beginnings appear. The larva hunts from ambush small invertebrates.

Nymphs are absolutely not like adults. They have a wide abdomen, a large head with eyes, antennae and a special mouth apparatus - a mask. This hunting aid transformed from the lower lip. When fishing, a daphnia mask is thrown forward and then returned to its place. For flat-bellied squeezed flat type of mask is characteristic. The legs are short and there are spikes on the back. Respiration occurs through the internal gill outgrowths. Larvae can breathe atmospheric air and oxygen dissolved in water. Metamorphosis into an adult occurs on land.

Information. Low-water ponds, in which flat-bellied fish are often left offspring, dry out in the summer with a long absence of rain. For this period, the larvae burrow into the sludge and expect favorable conditions.

Limiting factors

Dragonfly is a flat typical and numerous species, but it is reduced in number in some regions of the Russian Federation. Insects die as a result of water pollution. To preserve and restore the population, it is necessary to install treatment facilities, and control of local authorities over cluttering of the coastal territory. The squeezed flat stomach got into the Red Book of the Republic of Komi, Dagestan, Novgorod and Kostroma region.