Black dragonfly: a small representative of flying predators

Slender flying insects attract attention with the grace and maneuverability of flight. They are able to overcome tens of kilometers, dramatically change direction, hang in the air and plan. People are sympathetic to dragonflies that do not fly into houses, do not harm plants, and do not sting. Moreover, predators help reduce the number of mosquitoes, mosquitoes, and flies. Black dragonfly is one of the species that is not yet threatened with extermination. Little flyers prefer wetlands and temporary ponds.

Description of appearance

The black dragonfly or Danae (Sympetrum danae) is one of the small representatives of its family. It belongs to the genus Sympetrum. It is characterized by species-specific coloring, allowing the insect to be recognized at a distance. The body length of the black dragonfly is slightly more than 30 mm, the size of the hind wing is 22-28 mm. The structure of the insect is typical for the family of real dragonflies. A large head is movably connected to the chest. The body is elongated, the abdomen is elongated, its length is 18-26 mm. Males and females are different in color. Black color is a distinctive feature of adult mature males. Young males have yellow spots on the body, which gradually disappear.

Black eyes, occupying most of the head, touch in a small area. This structure of the organ is characteristic of dragonflies with different wings. Faceted eyes are made up of thousands of individual eyes perceiving the surrounding world. Antennae subtle, composed of 4-7 segments. Powerful twin jaws make it easy to tear prey to pieces.

The body and head of the female are yellow-brown in color, along the sides of the abdomen are two longitudinal black stripes. The chest and head are covered with hairs. From the posterior margin of the prothorax there is a vertical protrusion with a fringe of dark hairs. The chest on the underside and sides is covered with a black and yellow pattern. The transparent wings are long and narrow, with abundant venation. At the front edge of each wing there is a dark spot - the wing eye. This thickening helps maintain balance.

Interesting fact. The abdomen occupies up to 90% of the body length of a dragonfly.

The elongated abdomen consists of 11 segments formed by two chitinous scutes. Between them are membranes that allow the insect to bend. The abdomen of females ends with genital organs, and males have special appendages to hold the partner during fertilization. A black dragonfly has three pairs of limbs. Long legs are black, but may have yellow spots. The limbs are not intended for walking or running. The front pair serves to catch and hold prey. Strong claws and several rows of sharp spines help in the hunt. The function of the remaining limbs is to ensure the take-off and landing of the insect.

Larva - offspring unlike parents

Larvae emerge from the eggs very small. Their body is much shorter than that of adults. The head is large, the eyes are large, facetted. The oral apparatus consists of paired jaws, an unpaired upper lip and lower lip, transformed into a grasping organ - a mask. Sympetrum nymphs have a helmet-shaped mask. Young offspring prefers to stay at the bottom, often burrows in silt.

Outwardly, they do not look like adult dragonflies, but the hunter's instinct makes them wait for prey. They hide among aquatic plants and attack invertebrates, mosquito larvae and other insects. The legs of the nymphs are long, in the early stages of development they are regenerated after loss. For breathing, the larvae of various dragonflies use tracheal gills.

Information. Nymphs of black dragonflies are a type of short-crawling crawling larvae.

Lifestyle

The black dragonfly leads a typical lifestyle for its family - it is active during the day, and spends the night on plants. In the morning, winged insects like to bask in the sun. Males prefer to sit on open ground or stones. Rainy days with rain and wind await in shelters. Like most predators, they lead a solitary lifestyle. Dragonflies spend a lot of time in the air. During the flight, their wings are able to move independently of each other, this gives freedom to carry out maneuvers.

Damselfly dragonflies, if necessary, reach speeds of up to 60 km / h. On ordinary days, they make more measured flights at a speed of 15-20 km / h. Males do not show territorial aggressiveness. They expect partners near ponds where mating and egg laying takes place. The rest of the time the black squeezed bellies are spent in search of prey. They have no food specialization, dragonflies feed on all kinds of insects that they can catch. They hunt in the middle tier, choose tactical tactics.

The life expectancy of adults is 2-3 months. The years begin in mid-July and end in October. It reaches its peak in September.

Black dragonflies are fearful creatures. It is difficult to get close to them for observation. At the slightest noise, they break away and fly away. This behavior is explained by the huge number of dangers that await insects. Small body sizes make them vulnerable. Compressed bellies can become prey for birds, reptiles, mammals and relatives of a larger species. But with caution and endurance, you can wait until a small fragile black dragonfly sits on the palm of your hand.

Spread

The habitat of the black dragonfly is the entire Palearctic. This species is observed in the northern and central parts of Europe, in Asia, in the Far East and the Caucasus, in North America. The insect lives in most of Russia, except in the southern regions. Dragonflies choose standing ponds on acidified soils. They often settle near drainage ditches, in lowlands and swamps. Representatives of the genus Sympetrum are characterized by migration.

Propagation Features

During the breeding season, females flock to bodies of water with stagnant water. Partners with special appendages at the end of the abdomen capture females by the head. Before mating, they pump the sperm into the abdominal segment, where the copulative organ is located. From it, the spermatophore enters the partner's genital opening. An intricate mating pose connects dragonflies for a different period - from several minutes to hours.

Females lay eggs in water, sitting on a plant or immerse the lower part of the abdomen in a lake, hovering in the air. Some individuals drop eggs on the fly from the abdomen directly into the water. Masonry is up to 100 units, with a diameter of less than 1 mm. Most of the eggs will die from climatic conditions and enemies. In the temperate climate zone, eggs remain for the winter. Only with the advent of spring do small nymphs appear from them. They are waiting for 7-8 links before growing up. Larvae grow rapidly, so they are very voracious and actively hunt.

After the last molt, the nymph leaves the pond and selects on a vertical surface. Clutching a stalk of grass or a snag, she freezes upside down. Soon, the larva skin dries and cracks on its back. A young black dragonfly emerges from it. The insect needs time to harden the chitinous cover and acquire a permanent color.

The species of black dragonflies is not threatened with extinction, but they feel the negative impact of human activities on draining swamps.