The larvae of the rocker, Aeschna, live in stagnant bodies of water among plants and at the bottom. The length of the larvae reaches 35-45 mm. The body is thick and dense.
The head is large, tightly fused with the body. The antennae are short and seven-membered. The compound compound eyes are large. The mask is flat, the median lobe on the inner side is without long setae, its anterior margin is convex, armed with short hairs; lateral lobes without setae, large movable tooth; When folded, the mask does not reach the base of the legs of the last pair. On the sides of the first thoracic segment there are paired lateral projections, the shape and size of which vary in individual species. The abdomen is large, widened in the posterior half, without teeth on top; the lateral edges of the sixth to ninth segments are elongated into lateral spines. The length of the anal pyramid is equal to the total length of the last two abdominal segments.
The larvae of our most common Aeschna species differ from each other in the following characters:
Both lateral protrusions of the first thoracic segment are the same size or the anterior one is larger than the posterior one
Both side protrusions are sharp
The side projections are the same size, there is a notch between them with a right or obtuse angle - Ae. grandis
The front side protrusion is larger than the rear one, the notch with an acute angle is Ae. juncea
One or both side projections are blunt
The lateral projections are poorly developed, the notch between them is shallow - Ae. affinis
Lateral projections are well developed
The recess between the side projections with a right angle is Ae. suapea
The indicated notch with an acute angle is Ae. viridis
The rear protrusion is larger than the front
The anterior projection is sharp - Ae. isosceles
The anterior protrusion is blunt
The anterior edge of the middle plate of the mask is more than twice as wide as the posterior edge - Ae. coerulea (—Ae. squamata)
The anterior margin is more than twice as wide as the posterior margin - Ae. mixta (=Ae. coluberculus)
A-C larva of Aeschna grandis, general view (A), head from the side (B), male anal pyramid (C); D - left lateral projections of the pronotum of the larvae of Aeschna grandis (I), Aeschna juncea (II), Aeschna cyanea (III), Aeschna mixta (IV), Aeschna affinis (V), Aeschna isosceles (VI), Aeshna viridis (VII), M — tracheal system of the Aeschna larva; E - rectal bladder, with tracheal network, Aeschna larvae; G—schematic cross-section through the rectal bladder of an Aeschna larva; 3—tracheal gills of Aeschna larvae.
1 - head, 2 - antenna, 3 - upper lip, 4 - eye, 5 - pronotum, 6 - stigma, 7 - rudiments of wings, 8 - trochanter, 9 - thigh, 10 - tibia, 11 - tarsus, 12 - abdomen, 13 - lateral spines, 14 - anal pyramid, 15 - submentum (chin), 16 - mentum (chin), 17 - lateral lobe, 18 - movable tooth, 19 - anal appendage, 20 - cercus, 21 - cercoid, 22 - accessory plate (male), 23 - dorsal tracheal trunk, 24 - ventral tracheal trunk, 25 - visceral tracheal trunk, 26 - rectal bladder, 27 - rectum, 28 - tracheal gills.
Watcher Emperor, or watchman-overlord(lat. Anax emperor) - dragonfly from the rocker family
Breast green, with wide black stripes at the seams. The wings are transparent, 5 cm long. The wing plate is a contrasting gray-white color. Legs with long spines, from which in flight they form a “basket” for catching insects. The abdomen of an adult male is blue; that of a female is green or bluish-green, with a solid black jagged longitudinal stripe on the dorsal side. The eyes are large, blue-green in color.
The view is unusually wide range crossing almost everything natural areas Earth from Scandinavian Peninsula to South Africa, but in most areas within its range its distribution is quite local. IN Russia range is limited only to the southern half European part. The northern border of the range runs along the line Pskov Lake - Rybinsk Reservoir - Kuibyshev Reservoir- source Tobol River. It's possible that north of latitude Moscow The species is known from its migrations and does not normally live there. The distribution within the Russian part of the range is mosaic, with a clear tendency towards increased localization of habitats in the direction from southwest to northeast.
The Emperor Watchman lives in bodies of water in both open and closed forest landscapes. Larvae develop in stagnant and low-flowing reservoirs, with a thicket lifestyle predators- ambushers. The food spectrum of larvae is very wide and includes almost all small aquatic animals from Cladocera before tadpoles and fry fish. Development continues for 1-2 years, depending on the light and temperature conditions of a particular reservoir, as well as the availability of food. Molting to the adult stage in southern Russia occurs at the end May, at the northern limits of distribution in the middle June. Years imago continues until the middle August. Adult dragonflies are active predators, pursuing prey in the air. They feed on a wide variety of flying insects, but the main diet is usually mosquitoes. IN biotopic There are large differences in the distribution of males and females: the former are more concentrated near water bodies, the latter are scattered over large areas, preferring forest edges, bushes, and forest belts. During the breeding season, males are characterized by territorial behavior - patrol flights within the individual area, where mating and egg laying occur.
Dragonfly flat
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Dragonfly flat |
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Male dragonfly ( Libellula depressa) |
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Scientific classification |
Noticeably different from other types of dragonflies, the length of the wings is 33-37 mm, the length of the abdomen is 22-28 mm. The abdomen is strongly flattened and expanded. At the base of the wing there is a large dark brown spot; the rest of the wing membrane is transparent. Males and females are distinguished by the color of the abdomen: in males it is colored bright blue (usually bright blue) on top, and in females it is honey-colored. Brown.
It lives along the banks of reservoirs, does not fly far from water, prefers reservoirs with stagnant (pond, swamp) or weakly flowing water. In habitats they are found singly or in small groups (3-5 individuals). Adults can be seen sitting on near aquatic plants (reeds) and looking out for prey.
When laying eggs in water, the female hits its surface with the end of her abdomen. The larvae of this species of dragonfly develop for about 2 years, living during development in stagnant or weakly flowing reservoirs with a muddy bottom.
Predators hunt smaller flying insects with a quick attack from the air; strong legs with sharp spines are used to capture caught prey.
Cannot live in polluted waters
Control of littering in areas near populated areas, wastewater treatment. Currently, the species is listed in the Red Book.
Dragonfly "Big Rocker"
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Large rocker |
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Scientific classification |
Large rocker (Aeshna grandis) is a large dragonfly, growing up to 73 mm in length. It is easy to recognize even in flight by its brown body and bronze-colored wings. When this dragonfly is resting, you can notice blue spots on the second and third segments of its abdomen; however, only males have these spots.
Widespread in England, but more common in the south-east of the country. In Ireland it lives only in certain areas; it is not found in Scotland. Settles on overgrown ponds, lakes and canals. Patrols its hunting area, flying around its perimeter. Actively protects its territory from strangers. It flies mainly from July to September. The color of the larvae is black and white.
Brilliant beauty
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Brilliant beauty |
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Shiny beauty (male) |
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Scientific classification |
Brilliant beauty (lat. Calopteryx splendens) - dragonfly, belonging to family Beauties.
Body length - up to 50 mm, wingspan up to 70 mm . The body is shiny, from golden-green in females to bluish in males. They fly slowly, only near water, often perch on leaves and you.
Area- from Western Europe before lakes Baikal, also found in Western Asia And North Africa near rivers, lakes and others reservoirs. Perhaps they live in greater numbers in forested areas. The larvae live in streams And rivers with a small current and in standing reservoirs with clean water. The species is widespread, but is endangered in some areas. The species is quite vulnerable and locally widespread, included in Red books Kurgan And Chelyabinsk region, as a vulnerable species.
Protected in the Ilmensky, East Ural and South Ural nature reserves, in the Arkaim museum-reserve, in national parks " Taganay" And " Zyuratkul", Trinity Nature Reserve. Limiting factors are pollution of water bodies and economic development of coastal zones. The main goal of protecting the species is to prevent pollution of water bodies.
Church fly
Hoverflies (lat. Syrphidae) - family dipteran insects from the suborder short mustache (Brachycera).
One of the most extensive families short-whiskered dipterans, are found everywhere except deserts and tundras, and on all continents except Antarctica. There are 6,000 species in the world fauna, Palearctic- 1600, in Russia - 800. Fossil hoverflies are described from Eocene. Similar to OS, but they are actually harmless. They fly and wave very quickly wings. Color black and yellow. The body shape is imitated by Hymenoptera - this is how they camouflage themselves from enemies.
Hoverfly larvae - predators, phytophages or saprophages. The larvae of some species are pests of garden and ornamental plants.
Imago eat nectar or pollen plants.
Some species of hoverflies are associated with social insects. For example, members of the clan Volucella found in nests bumblebees, and representatives of the genus Microdon are myrmecophilous and found in nests ants And termites.
3 subfamilies, about 200 genera. Some members of the hoverfly family:
Krasotel
Beautiful odorous (lat. Calosoma sycophanta) - large bug from the family ground beetles. Features beautiful golden-blue-green elytra and sharp smell, which a beetle emits when in danger.
Large ground beetle, distinguished by bright golden-blue-green elytra. The head and pronotum are dark blue or blue-green. Body length 21-35 mm.
Life expectancy 2-4 years. Adult beetles overwinter in soil or litter. Pairing and laying eggs occurs in spring and early summer. Females lay from 100 to 650 eggs in the soil. After 5-15 days they appear larvae, which by mid-July complete development and pupate in the soil at a depth of 20-30 cm. Young beetles emerge from pupae already in August-September and here, in pupal cradles, they remain spend the winter.
Very active predator, hunts during the day, feeds caterpillars Volyanok And silkworms. Behind summer period one bug destroys 200-300 caterpillars gypsy moth, A larva- about 60 caterpillars and 15-20 pupae. Unlike most species of this genus, the krasotel does not live on the surface of the earth, but on trees. It climbs well on trunks and thin branches, hunting for caterpillars. Unlike most ground beetles flies well. Beetles live 2-4 years.
Pond strider
Water striders (lat. Gerridae) - a family of hemiptera insects from the suborder Bedbugs ( Heteroptera). There are about 700 species. The most common species of the genus Gerris. They live on the surface of the water. With the onset of cold weather, water striders leave water bodies and find refuge under the bark of old stumps or in moss.
The body and tips of the legs are covered with hard hairs that are not wetted in water (see Cassier's law), due to which water striders are adapted to glide through water. The water strider moves with two pairs of long and thin legs widely spaced - the middle and back ones. The shorter front legs are used to hold prey. Recent studies have shown that the front legs are the “engine” that provides changes in speed, and the other 4 legs are just a support.
The water strider turns, moving its legs in different directions. When overcoming obstacles they are able to make leaps. Body 1−30 mm long, dark brown, brown in color.
In addition to good vision, water striders also transmit and receive information through vibrations of the water surface. This interaction is also used by males when searching for a female for mating.
They feed on small invertebrates that have fallen to the surface of the water. They have a piercing-sucking mouthpart (proboscis) and external digestion; when feeding on solid food, they introduce paralyzing and tissue-decomposing substances into the victim’s body. They can suck human blood, but this is rare.
Water striders lay their eggs on the leaves of aquatic plants, placing them in one row, and the eggs are sometimes connected by a mucous substance; such a clutch looks like a long jelly-like cord containing up to 50 eggs. Laying takes place throughout the summer.
There are winged and wingless species. After wintering, winged representatives lose the ability to fly, as their flight muscles dissolve, providing insects with a primary supply of energy for hunting and reproduction.
Mosquito
Mosquitoes, or real mosquitoes, or blood-sucking mosquitoes(lat. Culicidae) - a family of dipterous insects belonging to the long-whiskered group ( Nematocera), female adults of which in most cases are a component of the vile complex. The oral organs are characteristic of this family: the upper and lower lips are elongated and form a case in which long thin needles are placed (2 pairs of jaws); Males have underdeveloped jaws - they do not bite. Legless larvae and mobile pupae of mosquitoes live in stagnant waters. Fossil mosquitoes have been known since the Cretaceous period. IN modern world there are more than 3,000 species of mosquitoes belonging to 38 genera. Representatives of 100 species belonging to the genera of true mosquitoes live in Russia ( Culex ), biter ( Aedes ), Culiseta, malaria mosquitoes( Anopheles ), Toxorhinchites, Uranotaenia, Orthopodomyia, Coquillettidia.
The life cycle of mosquitoes includes four stages of development: egg → larva → pupa → adult or adult.
Russian word mosquito goes back to praslav. *komarъ/komarь probably of onomatopoeic origin.
Mosquitoes are widespread throughout the globe and inhabit every continent except Antarctica. The widest range of the common mosquito ( Culex pipiens), which is distributed everywhere where a person is found - its main victim. In warm and humid tropical regions, they are active throughout the year, but in temperate regions they hibernate during the cold season. Arctic mosquitoes remain active for only a few weeks a year, when heat causes thermokarst pools of water to form on top of the permafrost. However, during this time they manage to breed in huge quantities - swarms of mosquitoes can take up to 300 ml of blood per day from each animal in a caribou herd. Eggs from mosquito strains in temperate latitudes are more resistant to the negative effects of cold than strains from warmer latitudes climatic zones. They can even withstand exposure to snow and freezing temperatures. In addition, adults can survive throughout the winter in suitable habitats (for example, warm and humid basements of residential buildings).
The spread of various species of mosquitoes throughout the world and their movement over long distances into regions where they are not native has been due to humans. Primarily due to travel along sea routes, in which eggs, larvae, and pupae of mosquitoes inhabit worn-out tires filled with water or are transported in cut flowers. However, in addition to sea transport, mosquitoes have effectively mastered travel on personal vehicles, trucks, trains and even airplanes. Thus, the spread of mosquitoes is difficult to control and even quarantine measures have proven to be ineffective and difficult to implement in practice.
Mosquitoes are insects with thin body(4-14 mm long), long legs and narrow transparent wings (wingspan from 5 to 30 mm). The body color of most species is yellow, brown or gray, but there are black or green-colored species. The abdomen is elongated, consisting of 10 segments. The chest is wider than the abdomen. The paws end in a pair of claws. The wings are covered with scales, clusters of which sometimes form spots. The antennae are long and consist of 15 segments. The mouthparts are piercing-sucking type. In females, the proboscis is long and consists of piercing setae; in males, it is without them.
The oral apparatus is hidden in the tube-shaped lower lip. Inside it there are several saw-like stiletto-like jaws (lower - lower jaws and high - upper jaws). With its jaws, the mosquito cuts a hole in the skin, plunges the proboscis deeper to the level of the blood capillaries, and through the same oral appendages, as if through a collection tube, it sucks blood.
Not to be confused: Insects from the family of centipedes, which have similar legs and the shape of their wings, are sometimes mistaken for huge mosquitoes.
Mosquitoes feed on nectar
For most species of mosquitoes, the source of blood (“feeders”) are warm-blooded vertebrates: mammals and birds. But some species are able to feed on the blood of reptiles, amphibians and even fish.
Most of the olfactory organs or olfactory system The mosquito specializes in searching for ("sniffing") sources of blood: of the 72 types of olfactory receptors located on the mosquito's antennae, at least 27 are configured to detect chemicals released in the sweat of animals and humans. In mosquitoes Aedes the search for a victim (owner) occurs in two stages: perception of the specific behavior of the object (movement), perception of its chemical and physical characteristics.
Lifestyle
Usually in temperate zone mosquitoes are active from May to October. If there was a lot of snow in the winter, and the spring is early, consistently warm and moderately humid, mosquitoes may appear as early as April.
Like all other dipteran insects, mosquitoes have 4 developmental phases: egg, larva, pupa, and adult. Moreover, all phases, except adults, live in reservoirs. Mosquito larvae and pupae living in water breathe atmospheric air through breathing tubes, exposing them to the surface. Mosquito larvae - filter feeders or scrapers - feed on aquatic microorganisms. The feeding of adults is often dual: females of most mosquito species drink the blood of vertebrates: mammals, birds, reptiles and amphibians; at the same time, the males of all species of mosquitoes, without exception, feed on the nectar of flowering plants. However, representatives of the subfamily Toxorhynchitinae have predatory larvae, while their adults (both males and females) feed exclusively on nectar.
In summer, adult females of blood-sucking mosquitoes are found both in nature in swampy and damp places, and in animal premises, in human homes on walls, windows, and shaded places. In winter, they can be found in livestock buildings, warm basements, and other buildings, where they are in an inactive state, or in torpor (if the temperature is below 0 ° C).
When choosing a victim, the female blood-sucking mosquito is guided by the smell of lactic acid contained in sweat (several kilometers), by carbon dioxide exhaled by a person (hundreds of meters) and by thermal radiation (several meters), by movement, and the female mosquito also reacts to light , preferring dimly lit rooms, which is why females in city apartments are mainly nocturnal.
Average lifespan of a female S. p. pipiens f. molestus depends largely on temperature. In laboratory conditions (such observations were not carried out in basements), on carbohydrate nutrition at 25 °C females live on average 43 days, at 20 °C - 57 days, and at 10-15 °C - 114-119 days; In the absence of food, life expectancy is greatly reduced. The lifespan of males in all cases is much shorter, so at 25 °C it is only 19 days.
A completely different picture is observed in ecotype mosquitoes pipiens, which under certain circumstances can become long-lived. If the females hatched from pupae in July - early August, then they all diapause and go to wintering, which lasts until March-May; After wintering ends, they reproduce and live for another 1-2 months. In total, the life expectancy of such females is about a year. For comparison, the lifespan of mosquitoes Aedes diapause at the egg stage is much shorter: they are born in the spring, reproduce and die by the fall.
The pupae are mobile. The respiratory openings of the pupa are not located on the abdomen, as in larvae and adults, but on the upper side of the chest, which the insect holds near the surface during breathing, and through which the mature adult emerges. On the empty shell of the pupa, the insect waits until its wings dry out before flying.
Reproduction
During the mating period, female mosquitoes attract the attention of males with a characteristic subtle sound, reminiscent of a squeak, which is created with the help of their wings. Mosquitoes catch sound vibrations with his sensitive antennae. Females squeak a little thinner than males, young ones - not as much as old ones. And male mosquitoes hear this and make a choice in favor of adult females. Mosquitoes form a swarm, where males and females mate.
A female mosquito lays 30-150, and even 280 eggs (in malaria mosquitoes) every two to three days. The egg develops into an adult mosquito within a week. Mosquitoes require blood to reproduce eggs, so the egg laying cycle is directly related to blood consumption. Only some urban subspecies can lay eggs without drinking blood, but they lay very few eggs.
Eggs are laid in stagnant or low-flowing reservoirs on the surface of the water (birth Anopheles And Culex), on wet soil at the edge of the water of reservoirs that dry up in summer and are flooded in spring, or stick to floating objects washed by water (at Culex) . The eggs on the water surface are connected in the form of a raft. The larva leaves the egg from the lower end.
Mosquito bite 
Mosquito bite sites
Before a female mosquito begins to drink blood, she injects saliva into the skin of her victim, which contains anticoagulants that prevent blood from clotting. It is the mosquito's saliva that causes itching, swelling, redness at the site of the bite, and in some cases, a severe allergic reaction. And it is through saliva that mosquito-borne infections are transmitted.
Meaning in human life Mosquitoes are carriers of dangerous diseases: malaria, yellow fever, dengue and some encephalitis. Of these diseases, malaria alone causes about two million deaths each year. In addition, their bites can cause itching and an allergic reaction, referred to in medical documentation as reaction to an insect bite.
Mosquito-borne diseases
Aedes aegypti- carrier of yellow fever and dengue fever
Anopheles albimanus- malaria carrier feeds on blood from a human hand
This photo shows a female Anopheles stephensi, which has drunk blood and begins to excrete an excess amount of liquid blood to make room in the intestines for more solid nutrients
Main articles: Malaria , Yellow fever , Dengue fever
Additional information: carrier
lymphatic filariasis (the main clinical sign is elephantiasis), which can be spread by a wide range of mosquito species;
viral diseases transmitted by vectors Aedes aegypti: yellow fever, dengue fever, chikungunya. Dengue fever is the most common cause of fever in travelers returning from the Caribbean, Central America and south central Asia. This disease is transmitted only through the bites of previously infected mosquitoes and cannot be transmitted from person to person. Severe cases of this type of fever can be fatal, but with timely and correct treatment, less than 1% of patients die from dengue fever;
The problem of West Nile Virus is a concern in the United States, however, there are no reliable statistics on the prevalence of cases of this disease throughout the world;
the Eastern Equine Encephalitis Virus problem is a problem in the eastern United States;
Tularemia is a bacterial infection caused by Lat. Francisella tularensis transmitted in various ways, including through the bites of flies and mosquitoes. Culex and lat. Culiseta , which are carriers of tularemia pathogens, as well as arboviral infections such as West Nile Virus.
Although HIV transmission was initially considered a major public health problem, practical considerations and epidemiological model studies suggest that any mosquito transmission of the HIV virus is, in practice, extremely unlikely (a "worst-case scenario").
Various species of mosquitoes are estimated to transmit various types of disease to more than 700 million people per year, in Africa, South America, Central America, Mexico, Russia and much of Asia, with millions of deaths - at least two million people die from these diseases every year , and the incidence rate is many times higher than officially registered.
Methods used to prevent the spread of disease or to protect individuals from mosquitoes in areas where the disease is endemic include:
vector population control aimed at mosquito control or eradication;
prevention of mosquito-borne diseases using prophylactic drugs and vaccine development;
preventing mosquito bites: using insecticides, mosquito nets and repellents.
Since most of these diseases are transmitted by older female mosquitoes, some scientists have suggested focusing on them to avoid resistance to evolution.
Caddisfly
Caddis flies(lat. Trichoptera) - a detachment of insects with complete transformation, with exclusively aquatic larvae. Currently, scientists have described 15,233 species, including 685 fossil species (Zhang, 2013), grouped into 45 families and about 600 genera, widespread on all continents except Antarctica, and on many oceanic islands. It is estimated that the world's fauna may contain up to 50 thousand species of caddisflies.
Trichoptera are closely related to the order Lepidoptera, and together the two orders form a superorder Amphiesmenoptera, or "Angioptera"; however Trichoptera have the most primitive characteristics.
Adult insects resemble small, dimly colored moths, but their body and especially the front wings are covered with hairs (rather than scales, like butterflies). which gave it its name Trichoptera: Latinized Greek Trichos(θρίξ) - hair and pteron(πτερόν) - wing. In some species, females go underwater to lay eggs. They are usually found in the vicinity of water bodies where their larval stages live. The transformation is complete. The larvae and pupae of the vast majority of species live in water or live in the thickness of the bottom of reservoirs; in rare cases, they constantly live outside the water or live near the coast in sea water.
Appearance of imago
Imago head
The head is rounded, hypognathous type - the mouth opening is directed downwards, with 2 large compound eyes on the sides and often with 2-3 simple ocelli on the upper and anterior surfaces. The parietal ocelli are close to the edges of the compound eyes, their optical lenses are directed to the sides. The frontal ocellus is located between the bases of the antennae and is directed forward, in some caddisflies from the families ( Hydroplilidae) it can disappear, and only the parietal ocelli remain. On the head there are well-developed hair warts protruding above its surface.
Caddis flies are easily recognized by a number of characteristics. The oral apparatus of adults is reduced, with the mandibles (upper jaws) non-functional or vestigial, but the maxillary (mandibular) and labial (labial) palps may be visible. In addition, adult insects have a well-developed proboscis (a synapomorphy of the order), formed by the fusion of the hypopharynx and labium and used by some species to absorb liquids.
The antennae are thread-like, usually comparable in length to the fore wings, sometimes noticeably shorter or much longer ( Macronematinae, Leptoceridae). As a rule, the maxillary palps are well defined (in females they are almost always five-segmented, in males from 5 to 2 segments), as well as the labial palps.
The chest consists of a short narrowed prothorax, a well-developed mesothorax, and a short metathorax. The coxae of the legs of caddisflies are greatly elongated, fused with the thorax, and are functionally part of the latter. The tarsi are long, five-segmented. The abdomen consists of 10 segments, the first tergite is trapezoidal, the first sternite may not be developed. In addition, the openings of pheromone glands are usually located on the sternites of segments V-VII. The sternites may bear stripes of thickened cuticle - sutures.
The wings are membranous, developed on the mesothorax and metathorax. The front ones are longer than the rear ones. Like the body, they are covered with hairs; sometimes areas of the wings may be covered with bristles. This feature is reflected in their name, meaning “hair-winged”. Along the edges of the wings, a marginal fringe of hairs or hair-like scales is developed; the size of this fringe in small species can be more than 2 times the width of the hind wing. Venation is represented mainly by longitudinal veins, separated by wide intervals of fields. The wings are always folded into a “house”.
The larval stages of caddisflies are aquatic, found in lakes, rivers and streams around the world and are essential components of food webs in these freshwater ecosystems. Adult caddis flies, unlike larvae, are terrestrial, eat almost no food, and their lifespan is limited to one to two weeks. Many of these insects have a characteristic unpleasant odor caused by the secretions of specific glands. This scent can serve as a repellent to caddisfly enemies, such as birds.
After fertilization, the female caddisfly lays eggs glued together with a mucous mass, attaching them to underwater rocks or plants. The larvae emerge from the eggs after three weeks. Like most fully metamorphosed insect larvae, they have well-developed mandibles and well-developed thoracic legs, but abdominal limbs are usually absent (except for a pair on the last abdominal segment, each leg may bear a strong "anal claw"). The transformation of a larva into an adult insect occurs through the pupal stage.
Types of caddisfly larvae
Larva with a house
Larva's house made of small shells
With few exceptions, caddisfly larvae are aquatic detritivores. Like butterfly caterpillars, caddisfly larvae are capable of secreting silk using a pair of long silk glands that open through a common duct on the lower lip. The three distinguished suborders are characterized by differences in the use of silk: for the formation of nests or tubes, or as glue for creating a variety of covers, often including sand and small pebbles, or pieces of leaves and twigs; each genus or even species builds a cover of a certain type.
Almost all larvae Trichoptera build a shelter or a house. The simplest form of covers is a reed tube. A more complex structure is a tubular case made of individual pieces of leaves, which the larva gnaws out and arranges in a spiral line. Depending on the type of caddisfly, the building material may vary. Sometimes the building material is arranged in a tile-like manner, and they are either pieces of reeds, or pieces of leaves and fragments of bark.
To build their cases, caddisflies use moss, blades of grass, pieces of dead wood, fresh wood twigs, pine needles, horsetail stems mixed with other plant debris; they attach small shells and sunflower husks to their home. Sometimes the buildings may not be made from plant remains, but from small shells, for example, peas, small coils, young meadows and other mollusks. In case of danger, the larvae climb into their house and plug the entrance to it with their heads, covered with chitin armor.
Less common are larvae that do not have caps - the so-called campodeoid larvae. Such larvae are mainly predators, building special trapping nets from thin cobweb threads. Such nets, shaped like funnels, are placed with a wide opening against the current and are attached motionless to aquatic plants, stones and other underwater objects.
The larva pupates underwater in a case constructed by it. The pupa has the rudiments of wings, very long antennae, large eyes and huge mandibles, with the help of which it destroys the cap. Thin thread-like gills are visible on the abdomen. The pupa may be equipped with long swimming legs. At the rear end of the pupa's body there are long bristles, with which it cleans the hole in the sieve-like cap, which is easily clogged with silt, and thereby provides access to fresh water. The opening of the anterior sieve cap is cleaned using bristles sitting on upper lip, and also, perhaps, with the help of elongated jaws. To exit the imago, the pupa floats to the surface, rowing its middle legs like oars. Adult insects emerge in about a month.
Aphid
Aphid (lat. Aphidoidea) - superfamily insects from the squad Hemiptera (Hemiptera ). Previously considered in the squad Homoptera (Homoptera). About 4,000 species of aphids are known, of which almost a thousand live in Europe. All aphids feed vegetable juices, many are dangerous pests of cultivated plants. In addition, many species are capable of spreading plant diseases in the form viruses and cause various anomalies in plants, such as Gauls and gall-like formations.
Aphids are small insects, the size of which does not exceed a few millimeters. Only a few species reach a length of 5 to 7 mm. Being phytophagous, aphids are equipped with a special proboscis that can pierce the surface of shoots or leaves. All species contain wingless and winged forms. The former ensure mass reproduction through parthenogenesis, and the latter contribute to the spread and change owner.
Aphids feed on plant juices rich in carbohydrates and need, first of all, the contained there amino acids. At the same time, they usually secrete large amounts of sweet solution, the so-called honeydew. It often attracts various other species insects And vertebrates.
Aphid development begins in the spring with the appearance of a larva that hatches from an egg laid on the main host plant in the fall. In some species of aphids, for example, grape phylloxera in certain environmental conditions there are overwintering larvae. The larva feeds on the juices of young shoots of a host plant of a certain species and after molting begins parthenogenetic reproduction, producing only wingless females. As a result of such reproduction, over a period of about a month, three generations with a total number of about hundreds of thousands of individuals can appear from one female. After lignification of the shoots, winged females begin to be born, which migrate to an intermediate herbaceous plant, also of a certain species. During the summer, more than ten more generations of wingless or winged females appear there as a result of parthenogenesis. In the fall, winged males begin to be born and fly to the previous host plant, where the females lay overwintering eggs. The rate of bisexual reproduction is lower than parthenogenesis - on the order of tens of thousands in the third generation, but it helps to overcome unfavorable environmental conditions .
Live birth in aphids
Aphid development stages
Aphids lay eggs, some species have live birth. Most aphid species reproduce over several generations using parthenogenesis. A certain generation is born winged and of different sexes. In species that change hosts, this occurs before colonization of a new plant or when the colony grows too quickly and the resulting overcrowding. Winged individuals are able to travel long distances and create new colonies in new places. According to new research, the birth of winged aphids may also be caused by special aromatic substances that are released by aphids when they are attacked by enemies, e.g. ladybugs. These warning substances cause great anxiety and increased movement in the colony. This creates an overpopulation effect, which causes the rapid production of winged offspring.
Plant characteristics
Rdest
Pondweed (lat. Potamogéton) - perennial aquatic plants; genus of the Rhododaceae family. Individual shoots or parts of plants float freely in water directly on or below the surface of the water.
The generic Latin name Potamogeton comes from the Greek. ποτάμι, which means river, and γείτων, which means neighbor, and indicates the habitat of plants of this genus.
The leaves are alternate, petiolate or sessile, of various shapes and sizes, from filiform and linear to oval and almost round. They can all be only underwater or underwater and floating on the surface of the water.
The inflorescence is a spike of grayish-green or brownish-green color. The flowers are bisexual, small, numerous, close together or spaced. Perianths of four rounded valve lobes, four stamens, without filaments. Bloom in July-August.
There are two possible options for flower pollination: the inflorescences rise above the water, and the flowers are pollinated by the wind; the inflorescences lie on the surface of the water, and then hydrophily and bestiality are possible.
The fruits have a woody pericarp and consist of four drupe-like lobes.
They reproduce vegetatively and by seeds. Seeds are dispersed by birds and water.
Pondweeds are cosmopolitan plants. They grow throughout the world in stagnant or slow-moving fresh or brackish bodies of water, often forming extensive thickets.
As of 2010, 143 species were known.
A finch (Fringilla coelebs) catching a dragonfly on floating pondweed leaves. Türkiye
Types of pondweed are not of great practical importance.
Pondweed feeds on aquatic mollusks, insects, and fish. There, in the thickets of pondweeds, on their underwater parts, and sometimes on the lower part of the leaves, they spawn.
Some types of pondweed serve as food for waterfowl, muskrats, and beavers. More often, fruits with a woody pericarp serve not so much for nutrition as for grinding food, being gastroliths.
The massive development of pondweed in water bodies impedes the movement of small vessels and contributes to silting and overgrowing of water bodies.
Mokrishnik
Chickweed average (lat. Stellaria media) - view plants sort of Chickweed (Stellaria) families Carnation(Caryophyllaceae).
Also known as woodlice, canary grass, chickweed, herniator, heart grass, biting midge.
It grows near homes, in vegetable gardens, weedy places, and sometimes along damp forest roads and clearings.
Annual herbaceous plant.
Stem cylindrical, creeping, branched, up to 10 cm high.
Leaves ovoid, short pointed; upper sitting, lower on petioles.
Flowers white, small, star-shaped, with two separate petals on long pedicels. Blooms in May - August.
Fruit - boxes with numerous round or kidney-shaped seeds.
In gardens it is a malicious weed, which is difficult to control due to the large number of seeds. One plant produces an average of 15,000 seeds. Seeds remain viable in the soil for two to five years. It also reproduces vegetatively by rooting stems. Develops from early spring until the onset of frost, giving several generations over the summer .
The aerial part of chickweed contains a lot carotene and especially ascorbic acid. In this regard, the above-ground, green part of the plant is used as food in cooking. salads- raw, and boiled - instead spinach V vinaigrettes, borscht and as a seasoning for main courses. The plant is also suitable for making soft drinks .
It is considered a good honey plant due to its long flowering period.
Chickweed grass is added to feed for pigs, geese, and chickens.
How is a medicinal plant used in homeopathy And folk medicine.
Chastukha plantain
Chastukha plantain, or water plantain (lat. Alisma plantago-aquatica) -view plants from the genus Chastukha families Chastukhovye (Alismataceae), type species of this kind.
plantain".
Common chastukha - perennial herbaceous plant with short thick rhizome. The height of the plant usually ranges from 20-60 cm.
Leaves with long petiole, heart-shaped or rounded base, ovoid or lanceolate-ovate plate, can reach a length of 20 cm; collected in the root socket. As with other types of chastukha, common chastukha is characterized by heterophylly(variegated): the underwater form of the plant has linear leaves.
Peduncles appear from the center of leaf rosettes and can rise up to 90 cm in height ; under aquatic plants inflorescences are usually not formed. Flowers actinomorphic, With double perianth. sepals greenish, remaining on the fruit. petals free, falling; white. Sepals and petals - three each. Flowers bisexual, with six stamens and numerous carpels, located on an almost flat receptacle. Length anthers- from 0.7 to 1.1 mm.
Fruit- small, flattened on the sides multi-nuts Green colour; break up into floating segments (fruits), each of which contains one seed. Fruitlets with an almost straight ventral side, with thin, opaque sides. Seeds have a smooth surface.
Number chromosomes: 2n = 14.
Area kind covers everything moderate regions Northern Hemisphere, the plant is also found in Africa and South Australia.
Common chastuha grows in various places with increased moisture - along the banks of reservoirs and in shallow waters, in swampy meadows, in ditches.
plant in fresh poisonous for livestock; contains substances that may cause irritation upon contact with human skin.
The plant is used in ornamental gardening- they are planted along the edges of ponds or in wetlands of gardens and parks; plants are valued, among other reasons, because they require virtually no care. Reproduction by seeds and division.
The rhizome of the plant is rich starch, edible after heat treatment (for example, baked).
The edibility of the rhizome after the death of the upper part of the plant remains in question. In 1994, 7 people died in the Tyumen region after eating autumn rhizomes baked on a fire. That same fall, in the Khanty-Mansiysk Okrug, a nineteen-year-old man miraculously survived after two days of intensive care after eating four raw roots.
Sphagnum moss
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Sphagnum |
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Sphagnum |
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Sphagnum |
Sphagnum, or Peat moss (lat. Sphagnum) - marsh plant, genus moss(usually whitish in color), from which it is formed peat.
Kinds sphagnum - spore perennials, have two generations. Dominates gametophyte.
Plants grow annually at the top and die at the bottom. Sphagnum - swamp moss, absorbs water throughout the body; rhizoids No. It is characterized by special water-storing cells on the leaves and stem (transparent, dead, hollow with holes); the cell wall is reinforced with thickenings. Water storage cells are surrounded by smaller ones photosynthetic cells. There is a stalk and a spore capsule. The body of sphagnum contains carbolic acid, which is antiseptic, killing bacteria. In this regard, moss almost does not rot and forms peat(1-2 mm per year). Due to the growth of sphagnum and other aquatic plants, forests become swamped and water bodies become overgrown: lakes turn into swamps.
It settles in damp places and contributes to rapid waterlogging of the area, as it is able to actively absorb and retain moisture. Is a forming plant sphagnum bogs. Most widespread in temperate zone Northern Hemisphere. Greatest species diversity V South America. IN Russia 42 species grow.
Due to small thermal conductivity used in construction business How insulating material in the form of plates, powder made from this peat; Also deodorizing means. Some peoples consider sphagnum a suitable material for warm diapers with which they cover their children in winter.
Sphagnum is used in floriculture as a filler in the preparation of earthen mixtures. In an air-dry state, sphagnum mosses are able to absorb water approximately 20 times more than their own weight, which is 4 times greater than the hygroscopic capabilities cotton wool(hence the name of the moss, “sphagnos” in Greek - sponge). In Germany and Canada, research is being conducted on the artificial propagation of sphagnum for use in soil mixtures.
The upper parts of the plant are used as medicinal raw materials. Sphagnum contains phenolic compound sphagnol and other phenolic and triterpene substances. In medicine and veterinary medicine sphagnum was used as a dressing material in the form of sphagnum-gauze pads. Because of bactericidal properties and ability to absorb large amounts of liquid was used by orderlies as dressing material on the battlefields during wars.
In Russia, sphagnum moss is also used to produce experimental food products, in particular, sweets and “Arctic crackers.”
Sphagnum is very resistant to decomposition, dried for a long time. It grows in swampy places and is harvested in summer.
Reed
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Reed |
Reed (lat. Scirpus) - a genus of perennial and annual coastal aquatic plants of the Sedge family.
Tall perennial plant. The stem is cylindrical or triangular, up to 2.5 m high. The flowers are bisexual, in spikelets collected in umbellate, paniculate or capitate
There are 52 known species distributed throughout to the globe. On the territory of Russia grow: Colchis reed, Maksimovich reed, eastern reed, rooting reed, forest reed, Vikhura reed.
The rhizomes contain a lot of starch. In the old days, flour was made from dry rhizomes.
Reed is used for weaving shopping bags, baskets, mats, rugs, as well as for decorative finishing of wickerwork made from wicker. Leaves are used for weaving. To get the green color, the reeds are cut in July, the beautiful yellow ones - in late August - early September. The plant is cut at a distance of 10-15 cm from the surface of the water. To preserve the color and elasticity of the leaves, they are dried in the shade.
In the last century, it was used for the production of building materials (reed concrete) based on cement or gypsum binders, mainly in rural construction.
Sedge
Sedges are perennial polycarpic herbaceous plants that form hummocks ( Carex appropinquata etc.), turf or groups of shoots connected by horizontal underground rhizomes.
Root system
The root system of sedge is represented by adventitious roots. The main root of sedge, like other monocots, dies 2-3 months after seed germination. In most species, the diameter of the first order adventitious roots is 0.2-0.6 mm:9. They usually develop at the base of the vertical part of the shoots and grow obliquely or vertically downwards. In some species that form hummocks, part of the adventitious shoots grows obliquely upward, located between the lower scale-like leaves of the shoot or in the axils of the leaves. In general, the root system of sedge is fibrous. In most sedge species, the adventitious roots are round in diameter; at Carex pilosa, Carex ericelorum they are four- or five-sided. The adventitious roots of hygrophyte sedges are, as a rule, densely covered with root hairs, while in mesophilic and xerophilic sedges the root hairs are poorly preserved and quickly die off. Root hairs Carex limosa, Carex nigra, Carex wiluica- bright yellow, Carex caespitosa, Carex omskiana- grayish or gray, Carex globularis- dark red.
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Root and shoots Carex michelii |
The shoot system in most species is of a sympodial structure (rarely monopoidal: 29), since each shoot, as a rule, ends in an inflorescence. Most species of sedges are characterized by rosette-type shoots, with nodes closely located in the basal part, from which adventitious roots, scale-like leaves and sheaths of ordinary leaves extend. In some species ( Carex hirta , Carex atherodes, Carex disticha etc.) there may be spaced shoots. Shoot development occurs within one ( Carex remota, Carex bohemica, Carex leporina etc.), several ( Carex aquatilis, Carex bigelowii , Carex atherodes), and more often than two growing seasons. Some types (for example, Carex vesicaria) are characteristic of winter monocyclic shoots: 209, : 213). In most sedges, all shoots are reproductive or potentially reproductive. After fruiting, the above-ground part of the generative shoot dies off, up to the “tillering zone”, and further growth of the plant is carried out due to lateral shoots.
In the direction of initial growth, sedge shoots can be apogeotropic (growing vertically upward), oblique-apogeotropic (growing obliquely upward), diageotropic (growing horizontally or somewhat arcuately, but in a horizontal plane), geotropic (growing vertically downward) and obliquely geotropic (growing obliquely downward) . All sedge shoots, which at the beginning of their development have a growth pattern other than apogeotropic, sooner or later change their growth to apogeotropic. Each species is characterized by shoots of a certain type. Species with oblique and apogeotropic shoots form tufts and hummocks. Turf species are characterized by the position of the buds of renewed growth at the soil surface. In species that form hummocks, gradually, with age, as a result of a more or less constant excess of the tillering zones of daughter shoots over the mother shoots, the buds turn out to be significantly raised above the soil surface. This way a hummock is formed. The height of the hummocks in some species can reach 60-70 cm:13.
According to the nature of renewal, all sedge shoots are divided into extravaginal and intravaginal. Most Central Russian sedges are characterized by extravaginal regeneration of shoots. In some species of sedges, shoot regeneration is mixed.
According to the classification of life forms proposed by Raunkier, sedges belong to hemicryptophytes. Based on the totality of shoot characteristics, E. Yu. Alekseev identified 7 life forms in Central Russian sedges:
false turfs (species with extravaginal shoots)
true turfs (species with intravaginal shoots)
horizontally rhizomatous species with underground shoots that do not branch during one growing season
horizontally rhizomatous species with underground shoots that branch during one growing season
creeping rhizomatous species with ascending (usually intravaginal) shoots and epigeogenic (false) rhizomes
stolon-rhizomatous species with elongated recumbent, usually extravaginal shoots
Stems are usually present only on reproductive shoots. They are (1.5) 3-100 (120) cm high, 0.3-5 (7) mm in diameter: 36, usually triangular, less often rounded or almost rounded: 112, with flat or concave edges, often covered with papillae, along the ribs are usually very rough, sometimes narrow-winged, low or highly leafy, with nodes that are not swollen, like in cereals, located mostly at the base and very close together, only in a few species spaced, hollow or solid, mostly central, rarely lateral or pseudolateral. In vegetative shoots, with rare exceptions ( Carex hirta,Carex disticha, Carex chordorrhiza, Carex pseudocuraica and some others), false stems formed by overlapping leaf sheaths.
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Sheet Carex leporina |
Leaf arrangement is alternate: 37, three-row. The lower leaves are scale-like, absent in some species. Based on the presence or absence of scale-like leaves, sedge species are divided by a number of authors into aphyllopodous and phyllopodous. Other authors believe that scale-like leaves are present in all types of sedges, but in some of them they are gradually destroyed during development. The scale-like leaves and sheaths of the lower, ordinary leaves can be brown, brown, reddish and blackish, and occasionally straw-yellow or whitish. Pubescence of scale-like leaves is very rare; among Central Russian species only in Carex globularis.
The median leaves have a triangular tubular closed sheath, equipped with a differently developed tongue in the form of a narrow membranous border at the junction of the sheath with the leaf blade and a linear, rarely lanceolate or broadly lanceolate: 37 leaf blade with parallel venation. The leaf blade may be single-folded ( Carex diandra, Carex humilis etc.), bifold ( Carex acuta, Carex silvatica etc.), grooved ( Carex lasiocarpa), grooved-triangular, unclearly bifolded and bristle-like along the folded, as well as flat. Single-folded leaves of Central Russian sedges are not wider than 4-5 mm, bifolded and indistinctly bifolded leaves vary in width from 2.5 to 20 mm:37. They differ in different types by width, consistency, color, the nature of the narrowing towards the apex (sharp or gradual), the presence or absence of protruding cross-veins. The side of the sheath opposite the leaf blade is usually membranous, rarely herbaceous. The shape of the tongue varies from elongated conical to arcuate, sometimes straight. In many species of sedges (for example, Carex buekii, Carex cespitosa, Carex lasiocarpa) the filmy part of the scale-like and lower green leaves, when the leaf is destroyed, breaks up into simple hair-like fibers or forms a mesh.
In a few species of sedges ( Carex chirta, Carex pallescens) leaf blades and sheaths of the middle leaves are pubescent with simple hairs. Pubescence in some species is permanent, while in others it is very variable. U Carex globularis scale-like leaves are pubescent. Puberty of leaf blades Carex pilosa ciliated. The edges of the leaf blades and the middle vein of the leaf from below in many species are rough due to the teeth present on them, which are usually directed upward, that is, towards the tip of the leaf. Much less often ( Carex digitata, Carex montana , Carex flacca) the denticles in the lower part of the leaf blade are directed downward, towards the base of the leaf. The surface of the leaf blades can be smooth or with hemispherical or hemispherical-conical projections, which are called papillae or papillae. The papillae, arranged in longitudinal rows, give the surface of the leaf, as well as the stems and sacs, a velvety character (for example, Craex canescens, Carex elongata and etc.).
The upper leaves are the variously arranged covering leaves of the individual spikelets of the inflorescence. Covering leaves are scale-like with a pointed or bristle-like apex or may consist of a long tubular sheath and a linear blade or a blade with a barely defined sheath, less often just one sheath, obliquely truncated or pointed at the top. The dimensions of the sheath and the covering leaf blade decrease in the direction from bottom to top.
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Flower diagram A- male flower B, WITH, D- female flower 1 - sac, 2 - peduncle |
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Female inflorescence Carex flacca |
The sedge gynoecium consists of 2-3 fused carpels. The style is usually long, hidden in the pouch or slightly protruding from it, mostly straight, sometimes curved down from the base or above, and then up again. The stigmatic branches can be long; as a rule, they are longer in forest species (in Carex bosrychostigma 12-15 mm long, y Carex pilosa 5-7 mm). The ovary is superior, unilocular, with one basal ovule.
Sedge blooms in early spring, at the end of April - June, in rare years at the beginning of July and later: 24. Most types of sedge are wind-pollinated plants, but, despite the inconspicuous inflorescences, some types of early-flowering sedge ( Carex ericetorum Pollich, Carex caryophyllea Latourrette) attract bees, which collect pollen from them and cross-pollinate
The fruit is single-seeded, indehiscent, with a hard pericarp, triangular in cross-section (if formed by three carpels) or biconvex (if formed by two), sessile or pedunculated, sometimes bearing a bristly or linear axial appendage at the base, enclosed in a sac. It is characterized as nut, paracarpous nut, variety of nut-sac, nut-shaped, nut-shaped, nut:112, paracarpous nut, nut-shaped, achene, paracarpous superior achene, superior achene and paracarpous dry drupe. The surface of the fruit is smooth, often glossy. The sac is membranous, thin-skinned or leathery (sometimes horny or corky), sessile or pedunculated, sometimes spongy-thickened at the base, with or without veins or ribs, smooth, pubescent, rough or finely papillary, biconvex, flat -convex, swollen or triangular, sometimes flat or winged, smooth, rough or serrated along the edge, without a spout or with a developed solid or variously split spout. Sedge seeds have a small embryo located in the center of the basal part of the seed and abundant nuclear endosperm. The peripheral cells of the endosperm contain oil, the rest contain starch and proteins. U Carex pendula And Carex arenaria Seeds with two embryos are often found.The fruits of sedges enclosed in bags - diaspores - spread in various ways. Initially they crumble under the influence of gravity. Fallen diaspores of a large group of species are dispersed by the wind. Species with highly swollen sacs are adapted to this type of distribution ( Carex physodes) and sacs with wing-shaped outgrowths ( Carex arenaria and etc.). The diaspores of some species are carried by water - these are species with highly swollen sacs with thin walls ( Carex rostrata, Carex rhinchophysa etc.) or with less swollen sacs, but with thick porous walls ( Carex riparia, Carex pumila etc.), which ensures their buoyancy. In many species, the sacs are carried by waterfowl, clinging to their legs along with dirt, in some - to the plumage ( Carex pseudocyperus, Carex bohemica). Sedge fruits are often spread by ducks, as they can remain viable in the digestive tract of ducks for a long time. Orange-red, somewhat fleshy, tropical-looking sacs are carried by birds Carex baccans. Some types of sedges with an elongated fleshy base of sacs containing oil and starch, ( Carex digitata, Carex omithopoda) are carried by ants. Dispersal of sedge sacs by muskrats, elk and domestic animals has been observed. Finally, the rudiments of sedges are also spread by people ( vehicles, with hay, shoes and clothes of people).
Chromosomes of sedges, as well as some other genera of the family Cyperaceae (Eleocharis, Scirpus):80, do not have a localized centromere, which is a very rare phenomenon among living things. The number of chromosomes varies from 2n=12 ( Carex siderosticta) to 2n=112 ( Carex hirta, Carex albata) . Chromosome numbers predominate in the range from 2n=32 to 2n=70, according to other data - from 2n=48 to 2n=64. Sedges are also characterized by the presence of aneuploidy; polyploidy is also known, but it is noted only within a few species:80.
Coastal sedge - hygrophytic species
Low sedge - xerophilic species
Sedge is an unpretentious plant; it can be found in the Arctic and southern Russia, in high mountains and steppe expanses. They are distributed throughout the globe, from the Arctic to the southernmost borders of the distribution of angiosperms, occurring in all climatic zones. Representatives of the genus are absent only in many arid deserts and are very rare in polar ones. In the tropical zone they are found mainly in the mountains, from the lower zones to the highlands, although some species live at sea level. Most species grow in the Northern Hemisphere, mainly in temperate and cold zones. Within the former USSR, according to some sources, about 400 species are found, according to others, 346 species (382 taxa of species and subspecies rank), growing almost everywhere, of which 103:40 species are found in the Russian Arctic.
Areas of general distribution of sedge:
Northern Europe (Spitsbergen, Jan Mayen, Iceland, Faroe Islands, Norway, Sweden, Finland, Denmark);
Atlantic Europe (Ireland, Great Britain, Northern Germany, the Netherlands, Belgium, the Atlantic regions of France and Spain, Portugal);
Central Europe (central and eastern regions of France, most of Germany, Switzerland, Northern Italy, Austria, Hungary, Czech Republic, Slovakia, Poland, Romania);
Southern Europe (Azores, Mediterranean islands, Central and Southern Spain, Southern France, most of Italy, former Yugoslavia, Albania, Greece, Bulgaria, European Turkey);
Western Asia (Turkey, Cyprus, Syria, Lebanon, Israel, Jordan, Iraq, Iran, the states of the Arabian and Sinai Peninsulas, Afghanistan);
Central Asia (Mongolia, arid regions of China - Dzungaria, Kashgaria, Tibet, Qinghai, Tsaidam, etc.);
East Asia (northeastern, eastern and southeastern regions of China, including the island of Taiwan; states of the Korean Peninsula, Japan);
South Asia (Pakistan, India, Maldives, Sri Lanka, Nepal, Bhutan, Bangladesh),
Southeast Asia (Myanmar, South China, the states of the Indochina Peninsula, the Malay Peninsula and the Malay Archipelago, the Philippines);
North America, including Central America and the West Indies;
South America;
North Africa (northern regions of the continent adjacent to the Mediterranean Sea),
Central Africa (tropical areas with adjacent islands);
South Africa (areas located south of the Tropic of the South);
Australia, including the island of Tasmania and the islands of Oceania.
Most sedge species prefer wet habitats - the banks of lakes and rivers, ponds, swamps, coastal and saline meadows, coastal and river sands, dunes; in the Arctic zone there are swampy tundras; sometimes they grow right in the water. But some types of sedge are also found in arid steppes (low sedge, early sedge) and even in clay deserts (thick columnar sedge). Other species prefer shady or light, deciduous or coniferous forests. Some xerophilous species are found on dry gravelly, gravelly-fine earth and rocky slopes. Mountain sedge species grow in mountain meadows, in the upper mountain belt, in cedar forests, and alpine steppes. Sedge slightly spread ( Carex remotiuscula) grows between stones and in rock cracks, thick columnar sedge grows at altitudes up to 1500-2000 m, and Carex decaulescens- up to 2000-3200 m. Arctic species sedges, growing in large quantities, play a very significant role in the formation of plant communities and determine their appearance. In the genus spectra of the Arctic, Eastern and Western Siberia, as well as the Far East, the genus Carex belongs to first place.
White water lily
White water lily is a perennial aquatic plant.
The rhizome is long, horizontal, branched.
The leaves are floating, round, up to 20-30 cm in diameter. The petioles of the leaves go under water, sometimes to a considerable depth. It happens that small bodies of water in which the white water lily grows dry up, and then the floating leaves with long flexible petioles die off. But after some time, small leaves appear on the rhizome on strong, erect petioles.
The flowers are white, 5-20 cm in diameter, slightly fragrant. The gynoecium is syncarpous, with a semi-inferior ovary. Flowering begins in mid-summer and continues until autumn.
Flower formula: .
The fruit is a capsule. The plant's seeds ripen under water. After ripening, they float to the surface.
The white water lily is found in the European part of Russia, as well as in the Urals, Western Siberia, Ukraine, the North Caucasus and Azerbaijan.
Rogoz
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Rogoz |
Rogoz(lat. Týpha) - the only genus of plants of the monotypic family Cattails (Typhaceae Juss., nom. cons.) order Ceramaceae.
Cattails are tall marsh grasses of temperate and tropical countries.
The leaves are long, ribbon-shaped, root-shaped; the stem ends with a brown spadix, in the upper part of which there are male flowers, and in the lower part - female flowers.
In the European part of Russia, up to four species of cattail are found.
Duckweed
Representatives of the genus are tiny perennial plants, usually floating in large numbers on the surface of standing waters. Only one species, tropical duckweed, is considered an annual plant.
Among flowering plants, duckweeds are the most reduced: they have no division into stems or leaves, and their entire body is represented by a green plate, which is sometimes called a leaf, bearing one root from below, and on the sides behind the same lamellar shoots, sitting in special recesses, the so-called pockets. The shoots grow, become isolated, and thus the duckweed reproduces.
Plates with one to five (seven) veins and with one or several layers of air cavities that allow plants to float on water contain raphid cells, but not enough a large number of pigment cells.
They bloom extremely rarely. The flowers are small, inconspicuous, unisexual, appearing in a pocket. They are collected in small inflorescences, consisting of two male flowers, reduced to two stamens, and one female flower, represented only by a pistil. The inflorescence is equipped with a small leaf appendage, reminiscent of the wing of the apiaceae. The ovary is single-locular, with two to seven amphitropic, atropic or anatropic ovules.
The fruit is a sac equipped with wing-like outgrowths and a keel, allowing it to float on the water. The seed is 0.4-0.9 mm long, with 8-60 longitudinal ribs, has a thick skin and small protein, most often remains inside the fruit during ripening, and during germination it opens with a lid.
Telorez
An aquatic plant with a rosette of numerous, broad-linear, hard, spiny-needle-shaped leaves at the edges, usually protruding from the water at the tip.
The flowers are dioecious with a perianth of three outer herbaceous and three inner white petal-shaped leaves. Male flowers are several in one spathe, on long stalks; stamens 11-15, surrounded by numerous staminodes. IN female flowers, solitary, rarely two, sessile, covered with a pistil with six bipartite stigmas and numerous staminodes.
Telorez is a plant that rises to the surface of the water during flowering. This happens because carbon dioxide accumulates in the leaves and stems and the telores becomes lighter than water. In the sun, it becomes “heavier”: the plant produces fruits, its starch reserves increase, and the plant sinks to the bottom again. By autumn, the amount of carbon dioxide in the leaves and stems increases again, and the plant floats up again. Having accumulated starch, they sink to the bottom again - to hibernate.
Cane
This plant is sometimes mistakenly called "reed", however Reed ( Scirpus) is a genus of plants in the sedge family ( Cyperaceae).
Large perennial herbs with long creeping rhizomes. The stem is hollow, strong, up to 5 m high. The leaf blades are linear-lanceolate. The inflorescence is a thick panicle.
The plant is eaten by many species of wild animals (muskrat, nutria, deer, elk), and in natural habitats it is an important component of the food supply.
The shoots of the young plant are used as feed for large farm animals.
Traditionally, reed was used by humans in construction; it was used to make roofs, construct fences, and was used as a thermal insulation material and filler.
Reed is used to make wickerwork, mats, and some types of paper. Reed can be used as fuel and is used to make reeds for wind musical instruments.
Sometimes reeds are planted to strengthen sandy areas or used for decorative purposes.
Hornwort
The depth at which hornwort grows varies. This is due to the fact that the plant is shade-loving and sensitive to light (experiments have shown that in bright light the plant dies), and therefore “selects” the depth that is optimal for it in a given reservoir. The maximum recorded depth is 9 m.
In favorable conditions, hornwort grows strongly, forming underwater thickets and displacing other plants.
Root absent. To remain in bottom sediments, plants develop special branches of the stem - the so-called rhizoid branches. They are whitish, with very finely dissected leaves; penetrating into the silt, they simultaneously perform the functions of anchors and absorbent organs.
Stem well expressed, hard, contains silica, rises from the water. A characteristic feature of hornwort stems is the very weak development of the conducting system; Absorption of minerals occurs throughout the entire surface of the plant. Hornwort tracheids, having completely lost the function of conducting water, have become storage cells in which starch is deposited.
By autumn, the growth points of the stems are covered with very close and darker leaves - and can be considered as analogues of winter buds.
Leaves sessile, repeatedly dichotomously dissected two, three or more times, located whorled. The terminal lobes of the leaves are often finely serrated, have a hard consistency, contain lime, and break on contact.
Both the leaves and other parts of hornworts are covered with hairs.
Another feature of representatives of this genus is that all parts of plants are covered with a cuticle (a film of a fat-like substance impermeable to water and gases, called cutin). Such a coating is almost never found in higher aquatic plants, while at the same time it is usually found in brown algae ( Phaeophyta), developing a layer of cutin on the surface of the thallus.
Flowers small (about 2 mm long), sessile, unisexual, without petals; collected in reduced inflorescences. Hornworts are monoecious plants.
Pollination occurs under water, which is a rare occurrence for flowering plants.
Fetus- nut. The fruits have spiky projections.
Seed- with a large embryo; without endosperm and perisperm; all reserve nutrients are located in thick cotyledons.
Series
Annual plant. The root is taproot, highly branched, thin.
The stem is single, erect, reddish, oppositely branched at the top.
The leaves are opposite, with short winged petioles, tripartite, with lanceolate serrate-toothed lobes (the middle lobe is larger), glabrous, dark green.
The flowers are dirty yellow, all tubular, collected in large, flat single or several at the ends of the branches of the basket at the top of the stem and opposite axillary shoots, the involucre of the basket is double-rowed.
The fruit is an obovate, wedge-shaped, flattened achene with two serrated awns. Thanks to these awns, the fruits easily cling to animal fur and human clothing and are transported over long distances. It blooms from late June to September, the fruits ripen in late September - October.
Distributed throughout almost the entire European part of Russia, Siberia, Central Asia, the Caucasus and the Far East.
It grows along damp river banks, along reclamation canals, near ponds and lakes, in swamps, in ditches, where it often forms thickets. It occurs scatteredly in meadows, as a weed in vegetable gardens and fields.
Chereda is a warm and moisture-loving plant. In cold, rainy springs it grows slowly and develops poorly.
Willow
The foliage of some species of willows is dense, curly, green, while others have sparse, see-through, gray-green or gray-white foliage.
The leaves are alternate, petiolate; the leaf blade in some species is wide, elliptical, in others it is quite narrow and long; The edge of the plate is entire in only a few species, while in the majority it is finely or coarsely serrated. The plate is either shiny, bright green on both surfaces, or only on the top; The lower surface of such willows is gray or bluish due to hairs and a bluish coating. The cylindrical petiole is quite short; at its base there are two stipules, mostly jagged, wide or narrow; they persist either only until the leaf is fully developed, or all summer. Stipules serve as a good indicator for distinguishing between different types of willows; one species called willow eared ( Salix aurita) has large stipules protruding in the form of ears. It is very interesting that stipules develop most on young shoots growing from the trunk or roots.
Stem-branched; branches are thin, rod-like, flexible, brittle, with matte or shiny bark, purple, green and other colors. Buds are also of different colors, dark brown, red-yellow, etc.; their outer integumentary scales grow together with their edges into a solid cap or sheath, which separates at its base when the buds grow and then falls off entirely. The apical bud on the branches usually dies, and the lateral one adjacent to it produces the strongest shoots, so to speak, replacing the dead apical bud.
Some willows bloom in early spring before the leaves bloom (eg. Salix daphnoides), others - at the beginning of summer, simultaneously with the appearance of leaves or even later (eg. Salix pentandra). The flowers are dioecious, very small and hardly noticeable in themselves; Only due to the fact that they are collected in dense inflorescences (catkins), it is not difficult to find them, and in willows that bloom before the leaves bloom, the inflorescences are clearly visible. Earrings are unisexual, or with only male or only female flowers; male and female catkins appear on different individuals: willow is a dioecious plant in the full sense of the word. A description of the structure of earrings and flowers is given below in the article: Willow; it also talks about pollination of willows.
The fruit is a capsule that opens with two valves. The seed is very small, covered with white fluff, very light, easily transported by the wind over long distances. In the air, willow seeds remain viable for only a few days; Once in the water, at the bottom of water pools, they retain their viability for several years. This is the reason why dry ditches, ponds, and silty mud scooped out when cleaning a pond or river are sometimes abundantly covered with willow shoots in a relatively short time. The young willow sprout is very weak and is easily drowned out by grass, but it grows very quickly; Woody willows generally grow unusually quickly in the first years of their life. In nature, willows reproduce by seeds, but in culture, mainly by cuttings and layering; a live willow branch or a stake driven into the ground quickly take root.
Motherwort
The height of adult plants is from 30 to 200 cm.
Tap root.
All types of motherwort are characterized by a tetrahedral, erect stem, sometimes branched.
The leaves are petiolate. The lower leaves are palmately lobed or palmately dissected, the upper ones are sometimes whole. The lower leaves are the largest, up to 15 cm in length; closer to the top, the leaves gradually become smaller.
The flowers are small. The inflorescences are spike-shaped, intermittent, located at the ends of the stems and branches in the axils of the leaves. The calyxes are bare or hairy, cut into five teeth by one third or up to the middle. There are four stamens. Blooms throughout the summer.
The fruit consists of four nuts 2-3 mm long, enclosed in the remaining calyx. The fruits spread by clinging to human clothing and animal fur with the sharp teeth of the calyx.
Two types of motherwort - Motherwort cordial and Motherwort hairy (five-lobed) - are valuable medicinal plants and are widely used in both traditional and scientific medicine as a sedative, similar to preparations from valerian, and also as an effective remedy for the treatment and prevention of heart disease. vascular diseases, without causing side effects. Motherwort is also used to treat epilepsy, Graves' disease, thrombosis, and gastrointestinal diseases.
In some regions of Russia, cabbage soup is prepared from motherwort.
The plant is a valuable honey plant. Motherwort honey is light golden in color, with a light aroma and specific taste [
Horse sorrel
The rhizome is short, slightly branched, multi-headed, thick with numerous roots.
The stems are erect, often solitary, bare, grooved, branched in the upper part, up to 90-150 cm high and up to 2 cm thick.
The leaves are alternate, rosette and lower - stem, elongated-triangular-ovate with a heart-shaped base, obtuse, wavy along the edge, obtuse at the apex, up to 25 cm long and up to 12-13 cm wide; the upper ones are smaller, ovate-lanceolate. The lower part of the leaf blade, especially along the veins, is densely covered with hard short hairs. All leaves are petiolate, the upper ones are on short petioles. At the base of the petioles, a filmy, reddish-colored trumpet is formed, enveloping the stem. The leaves do not taste sour.
The flowers are small, greenish-yellowish, bisexual, collected in small whorls into a narrow, long and dense paniculate inflorescence - thyrsus. The inflorescences are cylindrical, with a simple six-petalled perianth, its internal lobes at the fruits are rounded-heart-shaped, reticulate, with jagged edges; on one of them a large nodule develops, on the other two - smaller ones. The ovary is unilocular, one of three filiform columns usually with a large swollen seal, the stigmas are racemose. Blooms in May-June.
Flower formula: 
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The fruits are triangular, oval, brown nuts 4-7 mm long, enclosed in three overgrown perianth lobes. The fruits ripen in June - July. Propagated by seeds and vegetatively (by dividing rhizomes).
Acacia
Evergreen trees, up to 25 m high and trunk diameter up to 1.2 m, or shrubs. With or without thorns. In young plants, the bark is usually green, smooth, later heavily fissured, green, gray or brown. The root system is powerful, with a main taproot and highly branched horizontally in the upper layers of the soil.
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Flowers and inflorescences: Acacia alata. Acacia dealbata. Acacia crassa. |
The stipules are small, leathery or turned into spines, sometimes absent.
The flowers are small, numerous, solitary, in capitate inflorescences, cylindrical racemes or panicles, in the axils of leaves or at the ends of branches, erect or drooping, bisexual or heterosexual, in the latter case the number of staminate flowers significantly prevails over pistillate or bisexual.
There are 5 sepals and petals (4 or 3), free or several fused. The calyx is bell-shaped, serrated, less often fringed-dissected or absent.
The stamens are numerous (often over 50), separate or short fused at the base, almost always protruding above the corolla, free or short fused with each other and with the base of the corolla, yellow, orange, less often creamy, which gives color to the flowers. The ovary is sessile or pedunculated, glabrous, less often pubescent, with two or many ovules placed in one row along the suture. The pistil is thread-like, the stigma is protruding.
Flower formula:
The fruit is a bean elongated-ovate, lanceolate or linear, straight or variously curved, somewhat constricted or segmented, pubescent or bare, dehiscent or indehiscent, less often fractional, leathery and woody. The seeds are spherical to elongated ellipsoidal, often flattened, black to light brown. The ovule is thread-like, short, sometimes long, and wraps twice around the seed.Flowers are collected at the beginning of flowering, in May. Dry in the shade, under a canopy, and turn over often.
Elodea canadensis
It produces long, highly branched stems that grow extremely quickly and often reach a length of more than two meters. The stem, initially floating, easily takes root, putting out long, up to 40 cm, white roots. These stems are very long, thin, brittle and covered with oblong-linear leaves, which are arranged in rather dense whorls, three leaves in each.
The leaves are bright green, transparent, from oblong-ovate to linear-lanceolate, slightly curly, sharp, finely serrate along the keel. In the crown parts of the stem, the leaves are always lighter in color than in the lower ones.
The flowers are twofold: female and male and are located on individual individuals. The female flowers are solitary, small, consist of six petals, three internal and three external, and sit on long thread-like pedicels, their tri-stigmas are bright crimson and fringed. There are three sepals, they are reddish or greenish. These flowers bloom no earlier than the peduncle reaches the surface of the water. Male flowers are almost sessile, with nine sessile and anthers, which detach from the mother plant during flowering, or on an elongating pedicel, reaching the surface of the reservoir. In Russia, as in Western Europe, plants with male flowers are not found, and there are only one female specimens:295. Ovary with three to twenty ovules.
Bright green branches of elodea with a metallic sheen cover the bottom and, rising to the very surface of a shallow reservoir or aquarium, form a dense emerald network in the water, which makes elodea one of the decorations of the underwater landscape.
Elodea is also notable for the fact that in its tissues, as in the tissues of Vallisneria, the movement of the cytoplasm can be observed under a microscope. To make this observation, take a leaf from the top (end of the branch), place it in water on a glass and cover it with a coverslip. The strongest movement is in the leaf near the part where it is torn off. If the movement is very weak, it can be accelerated by placing the sheet in warm water (37-42 ° C).
White egg capsule
This is a perennial aquatic plant with a long, thick, fleshy horizontal cylindrical rhizome, flattened from top to bottom, greenish on top and whitish below, covered with numerous scars from fallen petioles and pedicels. Numerous roots extend from the rhizome.
The leaves floating on the surface of the water are leathery, dark green, long-petiolate, entire outermost, round-oval with a heart-shaped base. The leaves located in the water column are translucent, slightly folded with wavy edges.
The flowers are single, large yellow, sitting on peduncles protruding from the water. The calyx of the flower consists of five yellow, bell-shaped leaves that converge. There are many petals, they are narrow yellow, shorter than the sepals. There are many stamens. The ovary is oval-conical, multilocular with a sessile stigma. Flower formula: .
The fruit is juicy. Seeds with an air sac, thanks to which they are carried over long distances through water. The plant can bloom all summer.
Blue rocker (lat. Aeshna cyanea) belongs to the group of dragonflies (lat. Anisoptera). The beautiful dragonfly often attracts admiring glances, striking with the splendor of its dazzling outfit. Its unique beauty has inspired more than one generation of jewelers, poets and artists.
In Asian countries, it has long been considered a symbol of victory, and in folk medicine Medicinal preparations from dragonflies are used. IN European countries I have a completely different attitude towards her. She was often mistaken for a dark force carrying misfortune on her wings.
Spreading
The blue rocker is distributed in North Africa, Central Asia, the Middle East and Europe except Ireland, Greece and Turkey. The dragonfly lives at altitudes up to 1400 m above sea level. Favorite place its habitat is located near the shores of lakes, swamps and ponds.
Adults allow themselves to fly long distances to hunt in clearings and along the edges of forest clearings. The antennae of the blue rocker consist of granules of the mineral statolite, which helps the insect to navigate well in space.
Behavior
The dragonfly is a solitary hunter by nature. She can fly for many hours in a row at a speed of 9 m/sec and with a frequency of wing flapping up to 20 times per second. This insect is capable of flying long distances, but is a poor pedestrian. It may occasionally sit down to rest.
The large compound eyes consist of 28,000 simple ocelli.
A movable head and compound eyes make it much easier for this voracious creature to find food. The oral apparatus is armed with a pair of powerful jaws. The basis of its diet are mosquitoes, butterflies and mayflies.
The blue yoke eats small insects on the fly, and having caught a larger one, sits on the nearest plant and calmly eats it. After eating, the insect carefully cleans its legs and takes flight again.
With the onset of dusk, numerous flocks of dragonflies hunt for midges. In the heat of the hunt, they fly away to long distances from the reservoir, and sometimes they can fly into human habitation.
Reproduction
The breeding season lasts from June to October. During this period, cavaliers actively patrol areas with ponds and lakes in search of females. Flying over the surface of the water, the male performs intricate acrobatic acts in the air, trying to attract the attention of his partner. Females are limited to rapid flights in a straight line.
After mating, the male flies off to patrol the surrounding area again. The female and male mate with different partners. After mating flights, the fertilized female looks for a place to lay eggs. Wet moss or dead parts of the plant are suitable for this.
The female pierces the plant with her ovipositor and lays eggs in several rows. Only in the spring of next year will larvae 3 mm in size emerge from the eggs. Very soon they will begin their first molt. The blue rocker larva undergoes the molting process 10 times.
Living in a reservoir, it actively eats the larvae of flies, caddis flies and a variety of small invertebrate animals. She hunts with the help of a “mask”, which has 2 claws. During rest, this device is neatly folded under the chest. At the right moment, the larva opens it and sharply throws it forward, as a result the victim falls into a trap.
10 days before moving to land, the larva goes through a preparatory period.
The way of breathing changes completely, the eyes become larger. The wings, located in small pouches, increase in size.
At dusk, the larva leaves the pond and, coming ashore, climbs onto a blade of grass. After some time, a small crack forms on her back and head, and the last molt occurs. A completely adult insect is born. Its soft wings spread out and after a while harden.
The blue yoke goes on its first flight. The larvae that appeared at the beginning of the season stop growing with the onset of cold weather and only leave the reservoir the following spring to complete metamorphosis. Larvae that were laid at the end of the mating season develop very slowly. They complete the transformation within 2 years.
The life of the imago undergoes 3 periods of development. In the first period of maturation (up to 16 days for females, and up to 12 for males), males show off in dazzling decoration.
The second stage lasts about 60 days and is entirely devoted to the continuation of the family line. During this period, many individuals die. With the advent of the third period, the dragonfly's dazzling outfit fades, its worn-out wings refuse to serve, and the insect dies.
Description
The body length reaches 8 cm. The large head rotates in several directions. Huge compound eyes touch each other. The antennae, consisting of 7 segments, are equipped with organs of orientation in space.
The first pair of legs is directed forward and helps to climb plants and grab insects during hunting. Two pairs of luxurious wings are attached to the insect's chest. The wings of the posterior pair are slightly wider than the wings of the anterior pair.
The powerful chest consists of two segments of different sizes. The strongly elongated abdomen contains reproductive organs. The abdomen ends with pincer-like appendages, which the insect uses for self-defense.
The lifespan of the blue rocker imago is up to 6 months, and the larvae are up to 2 years.
Aeshna grandis(Linnaeus, 1758)
Order of Dragonflies - Odonata
Rocker family - Aeschnidae
Status. Category 3 - rare species. Status in Russia and adjacent regions. Protected in the Lipetsk and Saratov regions.
Spreading. European part, Transcaucasia, northern part Central Asia, as well as Siberia to the west of the lake. Baikal. In the Voronezh region. - in Verkhnekhava, Anninsky, Novousmansky, Novokhopersky districts.
Description. The rocker is large - a dragonfly with smoky wings and brown veins on them. There are no light stripes in the anterosuperior part of the chest. The length of the abdomen is 49-60 mm, the length of the wings is 45-49 mm.
Features of biology and ecology. Inhabitant of stagnant waters, but tolerating weak flow. It definitely requires an abundance of aquatic flora: the larva lives among aquatic vegetation. Adults feed on various flying insects, but their main food source is Diptera. The food spectrum of the larvae is wider; they feed on various large aquatic invertebrates, amphibian larvae and fish fry. Adults are found in June - August.
Number and trends of its change. Low.
Limiting factors. Pollution of water bodies, disappearance of characteristic near-water and aquatic vegetation as a result of strong anthropogenic pressure, unstable hydrological regime.
Security measures taken and required. The introduction of the species into small standing reservoirs with a stable hydrological regime is required; organizing an annual census of the species in model water bodies without removing individuals.
Information sources: Skufin, 1978; Agapova, 1979; Silina, 2002; Shishlova, 2004; Cadastre.... 2005, author's observations. Compiled by: O. P. Negrobov.
On a fine summer day over the lake you can see many brown dragonflies rapidly flying over the water surface. These insects are distributed throughout the globe. In nature, there are more than 6.5 thousand species of flying predators. This is an ancient order that once coexisted with dinosaurs. Having survived millions of years, the great rocker dragonfly is endangered by human activity. Pollution of water bodies has led to a sharp reduction in the number of beneficial insects.
Appearance of insects
The large rocker is a dragonfly that belongs to the family and genus of the rocker. Large insect reaches 60-75 mm in length, rear wing 45-49 mm. The female has a brown abdomen with small yellow spots. The chest is also brown, with oblique yellow stripes on the sides, and covered with hairs. Males have a brown or brown body, with blue spots on the side of the abdomen.
Information. The Russian name of the genus “yoke” is associated with the special posture of females who are not ready for mating. Insects bend their abdomen in the form of a rocker, refusing fertilization.
A characteristic feature of Aeshna grandis is that the compound eyes touch over a short distance. The complex structure of the organ, consisting of many small eyes, allows the insect to look simultaneously in several directions and quickly navigate in flight. The jaws are strong, the mouthparts are of the gnawing type. A dragonfly is not able to bite through human skin, but it easily tears flies and mosquitoes into pieces. The antennae or antennae are short and consist of 4-7 segments.
Features of the structure of the wings
The wing plates are transparent and smoky. The veins are brownish-golden. At the apex of the fore wing there is a noticeable dark brown thickening. This is a pterostigma, a dense area that allows you to increase the amplitude of the wing span and dampen dangerous vibrations. Each wing consists of two chitinous layers with their own system of veins.
The species large rocker belongs to heteroptera dragonflies. In representatives of this large group, in a calm state, the wings are located perpendicular to the axis of the body. When flying, they can use each pair of wings separately, which gives them wide maneuverability. Long limbs brown. They consist of 5 main parts, the thighs and lower legs are covered with two rows of spines. Each paw ends with a sharp claw. The forelimbs are necessary for dragonflies to hold prey, the rest for landing and take-off. Long flexible legs with spikes serve as a strong basket for catching insects.
Distribution area
The large rocker is common in the Central and of Eastern Europe. Dragonflies live everywhere from Ireland to the Urals, and are found in Kazakhstan, Transbaikalia, and the north of Central Asia. There are a large number of insects in England, but in neighboring Scotland the large rocker is a rare visitor. Favorite habitats are swamps, lakes, pits, and rivers with weak currents. Adults are often found in forest clearings or meadows, where there are many insects.
Reproduction
Dragonflies are insects with an incomplete metamorphosis cycle. After the egg and nymph stages, they become adults. Characteristic feature The rocker family is the division of territory by males. They patrol their areas, preventing rivals from approaching. During mating, males grab females by the head with their anal appendages. The sperm is pumped into a special organ on the second abdominal segment. The female leans her genital opening against the copulatory organ.
For laying, the female chooses one of the aquatic plants. She descends along the stem and sticks one egg at a time into its underwater part. Another way to hide future offspring is to lay eggs in a cluster of dead plants on the shore of a lake or swamp, on the inside of the leaves of water lilies. The shape of the eggs is oblong, one edge is pointed. Embryo development freezes during cold weather. The larvae appear only the following spring, at the end of April or beginning of May. They stay near the bottom of the reservoir; the nymphs feed on the larvae of other insects, crustaceans, and caviar. In the process of growing up, the offspring of dragonflies go through 7-11 molts. The insects have a spotted pattern on their bodies and multi-colored rings on their limbs. Grown-up larvae attack tadpoles and fish fry. The nymph stage takes up to two years.
Female great rocker lays eggs
Lifestyle
Insects are excellent flyers; they can reach speeds of up to 55-60 km/h. Their flight is characterized by planning. While looking for prey, dragonflies are able to hover in the air for a while. They fly several kilometers in search of comfortable habitats. Dragonflies are active during the daytime. They like it warm sunny days. On a cool morning, adults can be seen basking in the rays rising sun. The great rocker is one of the species that are active not only during the day, but also after sunset. They spend the night on the treetops. The adult summer period is from July to September.
Dragonflies are reliable human assistants in the fight against blood-sucking insects. Adults destroy mosquitoes and gadflies on land, and nymphs destroy mosquitoes in bodies of water where pests lay eggs. In a swift flight, dragonflies in flight grab flies and mosquitoes with their paws, and can catch a butterfly or even a small dragonfly.
Information. In some cases, dragonflies cause harm to humans. The adults prey on bees, and the larvae seriously harm young fish.
The larvae thrive in stagnant or low-flow water with a large number of plants. Weak limbs prevent nymphs from traveling and pursuing prey. They hunt from ambush. During the throw, the larva releases a stream of water, which sharply throws it forward towards the prey. Its breathing mechanism is designed so that the tracheal gills are located in the rectum. The nymph swallows a large amount of water and receives oxygen, the liquid is excreted through the anus. To capture prey, the larvae have a special organ called a mask. This is a modified lower lip, equipped with a movable joint and grasping teeth.
Interesting fact. The nymphs of the large rocker are very voracious; in a day they absorb an amount of food that exceeds their own weight.
After 2 years of development, the larva moves to land, where it settles on a vertical surface for its final transformation. Her skin dries out and cracks on her back. A dragonfly emerges from the old, tight skin. Her wings are soft and unformed. They wait for several hours for their wings to spread and harden. The final coloring takes several days to complete.
Threats to the species and conservation measures
Dragonfly larvae live in an aquatic environment and are sensitive to habitat pollution. As a result economic activity people end up in lakes and swamps with various chemical compounds, destructive for nymphs and other fauna. The disappearance of coastal vegetation has a negative impact on the number of dragonflies. The large rocker is one of the insects that requires protection. It is listed in the Red Book of the Voronezh region. To stabilize the number of individuals, small ponds with a stable hydrological regime are required.