Dragonfly beauty-girl: features of adult behavior and the development of nymphs

Dragonflies - winged predators, mesmerizing with grace and beauty. They are one of the oldest amphibiont insects that grow offspring in the aquatic environment. Dragonfly beauty girl is an amazing creature with a mother-of-pearl body and shiny wings. It is an excellent indicator of the cleanliness of a reservoir. If an insect settled on its shore, then there is no chemical waste in the water.

View description

A small dragonfly from a family of beauties fully justifies its name as a beautiful girl. The body of the male is blue-green with a metallic tint, the females are bronze-green. The glossy luster of the chitinous cover creates a unique impression. Insect length 45-49 mm, wing size - 30 mm. A distinctive characteristic of the Calopteryx virgo species is the absence of pterostigma - thickening at the leading edge of the wing. The female in her place has a bright spot. The photo shows that the female dragonfly of a beauty-girl has transparent wings, veins are gray-brown with a metallic sheen.

The head is large, movable, two complex faceted eyes occupy most of it. In equal-winged dragonflies, they are located on the sides. Antennae short and thin. The oral apparatus consists of an unpaired upper and lower lip and paired jaws. It is strong enough to break and chew prey. The dragonfly has 6 legs, consisting of 5 parts. The front pair is the shortest. All limbs are covered with two rows of spikes.

Information. Dragonflies do not use limbs to move. They need legs for landing and take-off. Front pair - serves to capture prey.

A related species of dragonflies lives in Russia - a brilliant beauty. Their body length is 50 mm, the color of the males is blue with a green tint and metallic sheen, and the females are golden green. The wings of males are transparent with a wide blue band, females are greenish. Two types of beauties can be easily confused. Dragonflies are slow, often sitting on coastal vegetation. They live in a wide territory from Western Europe to about. Baikal, in Asia and northern Africa. Representatives of a family of beauties in some regions of Russia were at risk. Beauty girl and brilliant beauty lose their habitat due to pollution of water bodies. Both species fell into the Red Book of the Kurgan and Chelyabinsk region.

Habitat

The view of a beautiful girl lives throughout Europe, in Western Siberia, Mongolia, and the Far East. Dragonflies can be found in Korea, Japan, in the northern part of China. To the north, the habitat extends to the Arctic Circle. Dragonflies prefer low places, rarely climb to a height of 1 thousand. m above sea level. Insects choose lakes or streams with a slow course. They are attracted to a large number of coastal vegetation.

Insect lifestyle

Dragonflies are dexterous predators, their diet consists of small insects and invertebrates. They grab and eat prey on the fly. Adults lead a daily lifestyle, they are most active on a clear sunny day. The night is spent sitting on bushes or tall grass. The summer period is from April to October. Females usually settle in forest glades, fly to the shores of water bodies for mating and laying eggs.The males choose their coastal areas where they live, hunt and expect a partner for procreation.

Interesting fact. Dense vegetation is necessary for dragonflies not only for relaxation, but also as a protection. Small insects with large wings are easily blown away by the wind.

The life of a dragonfly beauty-girl can be divided into two periods:

• Juvenile - begins after the exit of the imago from the larval shell. It lasts about 10 days. Dragonfly actively eats away from the reservoir, until it acquires a characteristic color.
• Reproductive - having reached puberty, insects return to water. Mating and egg laying occurs.

Dragonflies are insects with incomplete transformation; their life cycle has three stages: egg, nymph, and imago. Most of life passes in water - 2-3 years. The adult phase is much shorter - several months. Dragonflies are very shy, they soar into the air at the slightest noise or air fluctuation. A quick reaction saves insects from birds, amphibians and other enemies.

Nymph - predator in the pond

Dragonfly larvae are called nymphs; externally they are significantly different from adults. This is due to being in a different environment. Nymphs of beautiful girls prefer cool ponds with running water. Their body is elongated, brown, limbs striped. Small predators eat fish eggs, larvae of mayflies, mosquitoes, small invertebrates. Nymphs are sensitive to water pollution, they survive only in clean reservoirs. This is a kind of safety marker for a river or stream. In many countries of Central Europe, insects are listed in the Red Book. The lack of clean reservoirs jeopardized the existence of beautiful girls in Germany, Austria, and Switzerland.

Propagation Features

During the breeding season, females begin to circle above the water in search of a place for laying eggs. Noticing their reflection, the male begins courtship. The mating process is peculiar - the male holds the partner with special anal appendages in the prothorax. The female substitutes the genital opening for the second segment of the partner's abdomen. In such an intricate pose, they stay 5-10 minutes. Mating usually takes place on plants.

After fertilization, females lay 200-300 eggs on the stems of aquatic plants. Moreover, they not only sit on the water surface, but also dive for a long time. Beauty girl before diving envelops herself with an air bubble, so it can be under water for about an hour. The female lays oblong eggs, dropping down the stem of an aquatic plant, looking for cavities in it.

Larvae keep in places with a weak current, this allows better assimilation of oxygen. For breathing, there are three triangular gill plates at the end of the nymph's body. This organ is regenerated after an attack by predators or molt. The last stage of development ends on land. Nymphs emerge from the water, climb onto the stems of plants or driftwood, where they become adults.

Dragonflies are an important part of the environment, the reduction of their number negatively affects the balance of nature.