Label the organs of the grape snail. Helix pomatia - grape snail
The snail has been known since ancient times. The ancient Roman polymath Pliny the Elder reported in his writings breeding grape snails compatriots to feed the poorest classes. Specialized farms are still being created in a modern way, but the taste of shellfish is now more familiar to gourmets.
The name of the terrestrial gastropod has taken root because of its harmfulness to grapevines, but there are other variants of their names: apple snail, roof snail, Roman snail, Burgundy snail, or simply edible snail.
Features and habitat of the snail
Mollusks live not only in accordance with their name in vineyards, but also in gardens, deciduous forests and ravines with thickets of bushes. Limestone soil and alkaline reaction are the favorite environment of heat-loving snails.
European part, North Africa and Western Asia, South America inhabited by numerous populations of mollusks living not only in natural conditions, but also in urban areas, close to highways and residential buildings.
Due to their predilection for young shoots of plants, snails are classified as pests and are legally prohibited from being imported into some states. But at the same time benefits of grape snails obvious for the food and medical industries.
It is no coincidence that there are special farms for growing grape snails for various purposes. Ads " I'll buy a grape snail"is not uncommon today.
In size, this mollusk is perhaps the largest land mollusk in Europe. The body consists of a trunk and a shell, spirally twisted by 4.5 turns. The height of the snail's house is up to 5 cm, and its width is 4.7 cm. This is enough for the body to fit completely.
The ribbed surface of the shell's turbo spiral allows it to retain more moisture and enhances the strength of the house, which can withstand load pressure of up to 13 kg. The weight of the snail reaches 50 g.
The mobile and elastic body is usually beige-brown in color, covered with wrinkles to retain fluid and allow movement. Each snail has its own convex body pattern, sometimes barely noticeable. Breathing is pulmonary. Blood has no color.
The movement of the mollusk is ensured by a large leg. It glides along the surface due to the contraction of the muscles located in the sole and the stretching of the surface of the body. The length of the leg reaches 5-8 cm.
As the snail moves, thanks to special glands located in front, it secretes mucus that reduces friction. The average speed of movement of the snail is approximately 1.5 mm per second on any surface: horizontal, vertical, inclined.
It was believed that the mucous secretions simply dried out, but observations showed how the mollusk absorbs liquid using a groove on the sole. There is a constant circulation of mucus, which conserves fluid inside the body. If the weather is rainy, the snail does not spare the mucus and leaves a trail, since replenishing the supply is not at all difficult.
The shell color is usually brownish-yellow with dark transverse stripes. There are monochromatic, sandy-yellow individuals without stripes.
Shades may vary depending on the nutritional characteristics of the mollusk and the habitat in which it is necessary to camouflage itself from numerous enemies: frogs, shrews, lizards, birds, mice and predatory insects. Snails suffer from beetles that crawl into their breathing hole.
On the head of the mollusk there are tentacles with important vital organs. They are very mobile and rise and fall in vertical position, usually form an obtuse angle between themselves.
The anterior ones, up to 4-5 mm long, provide the olfactory function. The posterior ones, up to 2 cm in size, are the eye tentacles. Snails do not distinguish colors, but they see objects close up, up to 1 cm, and react to the intensity of lighting. All tentacles are highly sensitive: when touched lightly, they hide inside.
Character and lifestyle of the snail
Snail activity manifests itself in warm times: from the beginning of spring until autumn frosts. During the cold period they go into suspended animation, or hibernation. The rest period lasts up to 3 months. For wintering, mollusks prepare chambers in the soil.
Being good diggers, they make indentations with their muscular legs. The depth is from 6 to 30 cm depending on the density of the soil and other conditions. If the snail cannot burrow into hard ground, she hides under the leaves.
The mouth of the snail shell is covered with a special film of mucus, which, after hardening, turns into a dense cap. A small vent is maintained for air flow.
You can check this by immersing the snail in water - bubbles will appear as evidence of gas exchange. The thickness of such a plug depends on wintering conditions. The calcareous shell reliably protects the body of the mollusk from the external environment. During hibernation, weight loss reaches 10%, and recovery lasts for a month after awakening.
When a snail hibernates, it always lies down with its mouth facing upward. This allows you to maintain a small air layer, protects against bacteria and makes it easier to wake up in the spring. In order not to be flooded, she needs to get to the surface as quickly as possible in a few hours.
During the day, mollusks are passive, hiding in inconspicuous places under the cover of leaves or stones, on damp soil or damp moss. Air humidity affects the behavior of snails.
In dry weather, they are lethargic and inactive, sitting in shells covered with a transparent veil from evaporation and dehydration. On rainy days, the snail comes out of hibernation, eats the protective film at the mouth of the shell, the speed of its movement increases, and the period of active search for food increases.
An interesting fact is the regeneration, or restoration, of missing body parts by snails. If a predator bites off the tentacles or part of the head of a mollusk, the snail will not die, but will be able to regrow what is missing within 2-4 weeks.
Breeding grape snails at home today it has not become a rarity. This explains that in a number of countries, despite bans on the import of shellfish, interest in them remains and price of grape snail growing.
Grape snail nutrition
The main diet of herbivorous snails is young shoots of living plants, for which they are considered pests. What to feed a grape snail at home? They love fresh vegetables and fruits: bananas, pumpkin, zucchini, apples, cucumbers, carrots, beets, cabbage and more. In general, the list of plant crops includes more than 30 items, including plantain, burdock, dandelions, sorrel, and nettle.
In captivity, soaked bread becomes a delicacy for them. They can feed on other fallen greens and food leftovers only in conditions of lack of food. Then rotten plants and fallen leaves will definitely attract snails.
The tongue of a mollusk is like a roller with many teeth. Like a grater, it scrapes parts of plants. The greens turned into pulp are absorbed by the snail. Even nettle does not cause harm with its stinging hairs.
To strengthen the shell, the snail requires calcium salts. Animal food can also occasionally attract mollusks. Snails are endowed with a wonderful sense of smell. They can smell the smell of fresh melon or cabbage about half a meter away. lung condition breeze. Other odors are felt at a distance of about 5-6 cm.
Snail reproduction and lifespan
Grape snails are considered hermaphrodites. Therefore, two mature individuals are sufficient for reproduction. The mating period takes place in spring or early autumn.
Photo of snails mating
Eggs are laid in a prepared hole or in some natural shelter, for example, near the root weaves of plants. The clutch consists of 30-40 white shiny eggs up to 7 mm in size. The incubation period is 3-4 weeks.
Newborn snails emerging from eggs have a transparent shell with a curl of one and a half turns. Snails have been living independently since birth.
The young animals eat the leftovers eggshells, feeds on the soil and the substances contained in it until it emerges from the shelter. Formation occurs within 7-10 days in the nest, and then on the surface in search of plant food. Over the course of a month, snails increase in size by about 3-4 times.
In the photo the snail lays eggs
Only by 1.5 years does the snail reach puberty, but only 5% of those born reach this period. About a third of the mollusks die after the breeding season.
Average life expectancy in natural conditions is 7-8 years if she does not fall into the hands of a predator. IN favorable conditions artificial breeding domestic grape snail lives up to 20 years. There is a known case of record keeping a grape snail at 30 years old.
Despite the wide territorial distribution of shellfish, they have always been objects of human consumption due to the nutritional value of meat as food product and medical significance in the treatment of eye diseases, musculoskeletal system, stomach problems and for cosmetic purposes.
The mucus of gastropods improves the restoration processes of the skin after damage. Snails enhance collagen production and blood microcirculation, which help improve skin structure and rejuvenate it.
Preparing grape snails traditionally in Mediterranean countries and many European countries. Rich in protein and minerals, shellfish dishes are valued by gourmets. Best Recipes grape snails known to residents of France, Spain, Italy, Greece.
The snail is simple and mysterious at the same time. Coming from ancient times, it has changed little and still attracts human interest in its natural life.
Of course, everyone knows that a snail has tentacles - this is the first thing that catches our eye when we look at a snail.
It is worth noting that the tentacles are different for different representatives of mollusks. For bivalves and spadefoot mollusks, tentacles play an important role in swimming and burrowing into the bottom. In addition, the tentacles regulate the flow of water into the mantle cavity.
Only terrestrial pulmonary mollusks of the order Stylommatophora, to which the grape snail (helix), Achatina, Archachatina, Succinea putris, and Clavator belong, have two pairs of tentacles of the same shape as a grape snail. clavator), strophochilus, predatory snails, slugs, etc.
It should be noted that the presence of eyes at the top of the upper tentacles is far from common feature for all snails. This feature is characteristic of land pulmonate snails - Stylommatophora.
In aquatic snails, the eyes are located at the base of the tentacles and there is only one pair.
EYES.
Contrary to popular belief, the eyes of land snails are quite well developed - for mollusks. They even have a kind of lens-crystalline. Of course, the snail does not have necessary set cells to distinguish colors. And they are not equipped with ciliary muscles to change the curvature of the lens. All the same, snails see poorly, so the lower pair of tentacles is much more important.
LOWER TENTACLES- necessary for olfactory orientation, they are almost always directed downwards - to the ground. Stem cells on the surface of the tentacles give the snail the ability to smell and help in finding food. It turns out that snails also attract potential mating partners with olfactory hormones. Thus, small tentacles also help in finding a partner. During mating, both grape snails and Achatina often touch and feel each other with their lower tentacles, which can also help the snail better smell the hormone.
Each tentacle of the snail is equipped with its own contractile MUSCLE - RETRACTOR. If the snail contracts this muscle, the tentacle retracts and disappears. This can be observed especially well in young snails, which in most cases are still somewhat transparent.
However, the snail cannot use muscle to straighten its tentacles. She uses blood plasma (haemolymph) for this, which she squeezes into the tentacle.
SNAILS HAVING THREE PAIRS OF TENTACLES.
These include predatory wolf snails, Euglandina rosea and others. Not all predatory snails and slugs have a third pair of tentacles.
This pair of tentacles is used to explore the space ahead. The snail tracks its prey along a trail of mucus, as if sniffing. The third pair of tentacles in this case are the greatly expanded lips of the wolf snail, on which there are numerous olfactory cells.
The grape snail is one of our largest land mollusks. The spherical-twisted shell of the grape snail, reaching a height of 5 centimeters and a width of 4.5 centimeters, has 4-4.5 whorls, ending in a wide mouth.
The shell is usually yellowish-brown with wide dark brown stripes running along it. The color is very variable: there are stripes different widths and brightness, sometimes there are monochromatic snails completely devoid of stripes.
On the head of a grape snail there are two pairs of tentacles, one of which carries eyes, and the other serves as organs of smell and touch. Like all gastropods, the grape snail glides along the surface on its foot due to muscle contractions that pass in waves along the sole. At the same time, a huge amount of mucus is released, which reduces friction and facilitates movement on uneven surfaces. Previously, it was believed that the mucus secreted by the mollusk remained to dry on the path. However modern research scientists have shown that this is not entirely true. Mucus is secreted by the cochlea from a groove lying near the mouth opening, into which the duct of a special skin gland opens. Then it flows back along the sole, or rather, the mollusk spreads the mucus with its foot, but at the rear end of the leg it is absorbed back through a special hole on the sole. It turns out that the ribbon of mucus is constantly spinning, like a tractor caterpillar, passing from front to back outside the sole of the snail, and then from back to front inside the body. This allows animals to significantly save fluid costs, which is very important when living on land. The most interesting thing is that in good weather, when the mollusk crawls along a completely dry surface, it leaves almost no mucus trail, while during rain, when it is not difficult to restore water reserves in the body, a thick mucous trail remains behind the snail.
How do grape snails feed?
The vine snail feeds on rotting green parts of plants, mushroom mycelium and leaf litter. In addition, snails also consume fresh greens. In the mouth of a grape snail there is a muscular ridge (tongue), covered with a hard cap with teeth. This is the so-called radula or grater. With its help, the mollusk scrapes the leaves and stems of plants, absorbing the resulting plant pulp. She includes many species in her diet, including nettles, whose stinging hairs do not harm her. The grape snail has an excellent sense of smell: it smells a ripe melon already at a distance of 50 centimeters, and the smell of cabbage at a distance of 40 centimeters, however, with a light breeze. In still air, these same odors affect her only from 6 centimeters away. The snail got its name because of the harm it causes. vines. However, snails live not only in vineyards, but also in gardens, forests, and clearings overgrown with bushes. The mollusk spends the day hiding in its shell and comes out to feed at night.
Reproduction of grape snails
The grape snail does not have a clear timing for reproduction and egg laying. She reaches sexual maturity at four years of age. Mating usually occurs in spring or early summer. Depending on weather conditions in a given year, the snail may begin laying eggs in 20 or 60 days. However, if mating occurred in the fall, before the animals leave for the winter, the sperm remain viable in the spring next year when fertilization occurs. Grape snails lay fertilized eggs in the ground, digging a hole in it with their feet. Each egg is covered with a protective thick shell of carbonated lime and contains inside a large supply of nutrients in which the embryo is located. Usually in the spring, young snails emerge from the eggs, approximately 3-4 millimeters in size, which begin an independent life.
The behavior of snails during the mating period, their “love play” is interesting. Grape snails are bisexual organisms, i.e. each individual has a female and a male reproductive system, so one snail can play the role of both male and female. The snail's mating dance is a strict ritual with a completely precise sequence of movements. A certain irritation of one individual causes a strictly defined reaction in another, and vice versa. Therefore, the actions of both parties are clear and coordinated. Each signal stimulus is specific to one reaction, like a key to a lock. In the experiment, you can induce postures and movements characteristic of a mating dance by touching certain parts of the mollusk’s body. Two snails that meet stretch upward and touch with their soles, feeling each other with their tentacles. This is probably how they perceive and transmit signals about their partner’s readiness to mate. Then, pressing their soles tightly together, they lie on the ground for up to half an hour. After this, having become more active, the snails pierce the so-called “love arrow” into the partner’s body. This is a calcareous needle that forms in a special sac on the body of the mollusk and serves to excite the partner.
The grape snail is an excellent digger
Despite its slowness and large shell, the grape snail is a good digger. With the onset of autumn, she digs a hole in the ground with her muscular leg, where she hibernates. The depth of burial in the soil is different and depends on various external conditions, primarily on the density of the soil. The behavior of a snail when digging a hole consists, like the mating dance, of a strictly defined set of actions observed under all conditions. The snail grabs a lump of soil with its head end, then bends its head and presses the soil to the sole, moving it towards the rear end. Wave-like contractions of the leg drive the lump to the end of the body and push it out over the shell. Then the snail lowers its head into the hole again and grabs the next lump of earth. Gradually, the hole deepens, the snail sinks into the soil, and from above it is covered with discarded clods of earth. If the ground is very dense and it is not possible to dig a hole, the snail, falling over on its back, scoops up fallen leaves, under which it hibernates.
Having burrowed, the snail closes the entrance to the shell, for which it tightens the mouth with a calcareous membrane-lid. This cap is formed from solidified mucus, “squeezed out” from the body of the mollusk by special teeth located along the edge of the mouth of the shell. When the leg is pulled into the shell, the protruding teeth scrape off the mucus from it, to which granules of calcium carbonate are added. An “vent” remains on the surface of the cap through which gas exchange occurs. You can verify the function of the vent by placing the snail in water. After some time, air bubbles begin to escape through it. In spring, through this hole, the snail takes air into its lungs and, waking up, sheds its winter cap.
When overwintering in the soil, snails are always positioned with their mouths facing upwards. This is due to several reasons. Firstly, contact with the soil makes it difficult for the snail to breathe, secondly, it facilitates the penetration of fungi and bacteria into the shell, and thirdly, it causes the lid to become damp. In the normal position with the mouth facing upward, there is always an air space between the cap and the soil layer; in addition, when waking up, the animal can more quickly get to the surface if the mouth is facing upward. The snail's awakening time is only a few hours, which is very important in the spring when there is heavy melting of snow, when the snail runs the risk of being flooded.
The protective cap is formed not only before wintering, but also during the summer drought. Loss of moisture is the main and constant danger that threatens terrestrial mollusks. Evaporation occurs through the mouth. The lid, saturated with granules of carbonated lime, effectively retains it, thus being protective device. In addition, the lid protects the resting mollusk from mechanical damage, penetration of harmful microorganisms and from enemies.
The grape snail has the ability to regenerate, i.e. restoration of lost body parts. If suddenly, as a result of an attack by some predator, she loses tentacles with eyes and even part of her head, this is not such a disaster, since after 2-3 weeks she will have the missing part.
Where do grape snails live?
The grape snail is widespread in Southern and Central Europe, Western Asia and North Africa. This is a heat-loving species that lives in deciduous forests and bushes, often near populated areas.
Recently, the grape snail was brought to the outskirts of Moscow and St. Petersburg, where it thrives. For example, a large population of these snails was found in an old deciduous forest in the northern part of the Prioksko-Terrasny Nature Reserve on the Oka River. In Moscow itself, snails were found in one of the arboretums literally 20 meters from a busy highway.
Grape snails live a long time, up to 6-8 years, and in cages they can live for 10-12 years. In a number of countries, for example in France and Italy, grape snails are eaten boiled.
The closest relative of the grape snail is the Bukh snail - rare view, recommended for inclusion in the Red Book of the Russian Federation, is found in the Caucasus. This moisture-loving animal lives in forests and gardens near water bodies. Bukha snails live for about 3-4 years, and in the second year they begin to reproduce. They feed on green parts of plants.
(Helix pomatia) – terrestrial gastropod, a representative of the order of pulmonary snails of the helicid family. Europe is considered the homeland of grape snails, where they are found almost everywhere. The grape snail is the largest snail in Europe. You can meet the grape snail in thickets of trees and shrubs, in clearings, forest edges, gardens, parks, and meadows. Evidence moves by sliding on the sole of the foot. Mucus is secreted from the front of the snail's leg, which makes it easier for the snail to glide along various surfaces. Since ancient times, grape snails have been eaten.
Description of the grape snail.
snail body consists of a body and a shell. The snail's body consists of a head and legs. Internal organs snails are located in the mantle of mollusks. The mantle is a kind of pouch. In terrestrial mollusks, the mantle serves as a pulmonary sac. Part of the mantle is visible from the outside.
It is curved in a spiral 4.5 turns to the right, and when the snail emerges from the shell, it moves clockwise in the shell. The spiral of the snail shell is convex and lies in different planes.
Alternating dark and light stripes run along the length of the first 2-3 large turns of the shell. The shell color of the grape snail consists of light yellow and yellow-brown flowers of different shades and can be lighter or darker. The color of a snail shell depends on environment and habitats. This allows the snail to camouflage itself from enemies and be less noticeable in this type terrain. The color of a snail's shell can change depending on the food the snail eats.
The volume of the shell of an adult grape snail allows the snail to completely hide its entire body in the shell. The diameter of the shell of an adult snail is about 4-5 cm. The outside of the snail's shell is slightly ribbed. Thanks to these ribs, the sink becomes stronger and lighter, and its surface is a little larger, which allows a little more moisture to accumulate on the surface.
Leg and torso. In an adult grape snail, the leg length usually reaches up to 5 cm in length. A snail can stretch its leg up to 8 cm in length if it needs to stretch out strongly while moving from one leaf of a plant to another. Grape snails have a very elastic body. Such a flexible body allows the snail to masterfully bend and stretch, to overcome the air space between the leaves of plants when moving along them.
The body of grape snails can have different colors. Just like there can be different colors of the shell. Typically, the body color of the grape snail is beige with brown tints. The color of a snail's body can change depending on the food the snail eats.
The snail's body has its own and unique pattern. In rare cases, the pattern on the snail's body is faint or absent altogether, and in these cases the color of the snail's leg is usually monochromatic. The entire body of the snail is covered with wrinkles and folds. Between the folds, parts similar in shape to quadrangles are formed. Wrinkles on the snail's body significantly increase the surface area of the leg. Wrinkles accumulate more moisture, which is so necessary for the snail. After all, a snail needs a lot of mucus to move, and to produce mucus, a snail needs a lot of water. Wrinkles on the body and ridges on the shell help accumulate as much moisture as possible.
Snail slime transparent, viscous, dries quickly in the air and shines. To produce mucus, the snail requires a lot of water. Mucus provides the snail with gliding and serves as a lubricant for the path along which the snail crawls.
Tentacles. The grape snail has 2 pairs of tentacles of different sizes. They are located above the oral opening of the cochlea. The anterior labial tentacles are 2 to 5 cm long and perform the function of smell. The posterior eye tentacles are 1 to 2 cm long. At the ends of the posterior short eye tentacles are the snail's eyes. The snail's eyes do not distinguish colors, but they distinguish the intensity of light and allow the snail to see at a distance of about 1 cm. The snail's tentacles are very, very mobile, they can take different positions relative to each other. All snail tentacles are very sensitive. When touching an object, the tentacles instantly fold inward. The posterior eye tentacles react not only to touch, but also to bright light.
Internal structure of the cochlea. The snail has a digestive system, has pulmonary respiration, a heart and colorless blood. The snail has a nervous system, a reproductive system and an excretory system.
Lifestyle of grape snails. The grape snail leads an active lifestyle from spring to autumn. With the onset of the first cold weather, the grape snail burrows into the ground to a depth of about 25-40 cm and falls into suspended animation. During suspended animation, the mouth of the snail's shell is blocked by a calcareous plug called epiphragm. The thickness of the epiphragm varies and depends on the surrounding temperature and climate.
The epiphragm is a layer of mucus frozen in air in the form of a film. Protective film appears due to the compression of the snail in the shell, while mucus is released, and it quickly hardens on the edges of the shell. The snail's body is drawn deeply into the shell and a layer of air is formed between the body and the epiphragm. In this way, snails are protected from unfavorable conditions: cold or drought. For wintering, grape snails often choose the same places and shelters.
What does the grape snail eat? Grape snails are herbivores, eating a variety of living vegetation. Grape snails eat grapes and grape leaves, cabbage, sedum (hare cabbage), horse sorrel, plantain, dandelion, burdock, nettle, horseradish, strawberry leaves and many other plants. The snail loves grapes most of all, which is why it got its name - the grape snail. To grow a shell, the snail needs calcium salts.
How does a snail breathe? The grape snail breathes using its lungs. The snail's breathing hole is scientifically called a pneumostome. The pneumostome is a special respiratory organ in pulmonate snails and is part of respiratory system. This breathing hole is located among the folds of the mantle, on the side where the whorls of the shell are located. The grape snail breathes through this breathing hole. In grape snails, this hole opens and closes at intervals of about 1 minute.
How long do grape snails live? Life length largely depends on the living conditions of the snail. In nature, snails live for about 7-10 years. In favorable conditions and under good circumstances, grape snails can live longer, living up to 20 years or more, if they are not eaten by predators. In favorable home conditions, snails can live for more than 20 years. Molluscarium is used to keep snails at home.
Anabiosis in snails. Grape snails go into suspended animation, which lasts 3-5 months depending on the place where the snail lives. Before the onset of suspended animation, the grape snail selects a place convenient for it and attaches its foot to it. Then, holding the tip of its foot, the snail gradually folds its body into a shell and secretes mucus. The mucus quickly hardens and turns into a protective layer, a thin film called epiphragm. Next, when the epiphragm has tightly closed the hole, connecting with the edges of the shell, the snail completely removes its leg and rolls it up in the shell. A small layer of air forms between the epiphragm and the body of evidence in the shell.
How do snails crawl? The snail moves along the surface on its muscular leg. With the help of muscle contractions, the snail pushes off the surface and slides along the mucus, which it secretes to facilitate movement and reduce friction. The glands that secrete mucus in the snail are located in the front part of the body. Snails crawl slowly, but they can crawl both on horizontal and vertical surfaces. It is easiest for a snail to crawl on smooth horizontal surfaces, close up leaves plants, glass, smooth wet stones. To move along the ground, the snail needs to exert more effort and spend more mucus on movement.
After the snail moves, a trail of dried mucus remains behind it. Using such snail tracks, you can also detect the snails themselves, since snails crawl quite slowly and if the tracks are fresh, then the snail is somewhere nearby.
How fast do snails crawl? Snails crawl slowly. The maximum speed of snail movement is about 7 cm per minute.
Snail breeding. How do snails reproduce? Grape snails are hermaphrodites and have both male and female reproductive organs. Thanks to this, all grape snails can give birth. Snails mate in spring and autumn. When a snail seeks to mate, it behaves unusually, fussing, climbing, stopping, lifting its head, as if it had lost something and was diligently searching. When two snails have found each other and met, they begin love games, which last about 2 hours, after which the snails crawl away. During mating, 2 snails press together with the soles of their feet. The genital organs of snails are located slightly below the oral cavity and look like flexible white outgrowths that appear and curl inward during sexual intercourse. During sexual intercourse, snails' breathing holes are open almost constantly.
The birth of grape snails. Snails are born from eggs. After love games, snails lay eggs and place them in the ground at a depth of 5-10 cm. The snail egg is soft and white in color, spherical in shape with a diameter of 5-7 mm. A small snail is formed in the egg. The diameter of the shell of a small grape snail at the time of birth is about 2 mm. While in the egg, the small snail, after complete formation, begins to eat the remains of the egg shell and then begins to slowly crawl up to the surface of the earth. It takes a small snail up to 10 days to overcome this 5-10 cm long path. On its way, the small snail feeds on the soil and the substances contained in this soil.
All about grape snails. Grape snails have many enemies. Various beetles can crawl into the snail's breathing hole and get inside the snail. Moles, hedgehogs, lizards, shrews and even some types of predatory snails feed on vine snails. People also eat grape snails. Since ancient times, people began to eat snails and even breed them for these purposes. Currently, snail breeding farms have been built in a number of countries. On these farms all favorable conditions have been created for rapid growth and reproduction of grape snails. On such farms, snails are raised for further sale. Many people keep grape snails as pets at home. For this purpose they make a molluscarium - this is a glass house for snails in which they live. Under favorable conditions, grape snails can live for quite a long time.
The grape snail feeds on grape leaves and shoots. In addition to grapes and grape leaves the grape snail eats many other plants and crops and is therefore considered dangerous pest Agriculture. Grape snails are exterminated as a pest, and in some countries there are even bans on the import of grape snails into the country. In some European countries, the grape snail is a rare specimen and the grape snail is protected by law from extermination of snails.
Grape snails in cooking. In a number of countries, grape snails are eaten. Grape snail meat contains about 10% protein, 30% fat, 5% carbohydrates, vitamins B6 and B12, calcium, magnesium and iron. It is believed that the taste of grape snail meat is much better than the taste of meat of other types of edible snails.
Snails are prepared by baking them in the oven along with the shell in vegetable oil and using seasonings. Place the prepared snails in their shells on a baking sheet, add vegetable oil and place in an oven preheated to 200 degrees. Cook until the oil boils and turns golden. Before cooking in the oven, grape snails are washed, their shells and bodies are cleaned, and they are prepared in a special way for cooking.
Snail shells can be used for cooking many times. Escargot is a famous gourmet French dish prepared in the oven from grape snails, as well as from other types of edible snails.
Special features of grape snails. Grape snails have a light brown shell with a diameter of about 4 cm.
Relatives of snails. Snails have relatives, slugs or otherwise slugs. Slugs, unlike snails, do not have shells. In addition to slugs, snails also have other relatives: mollusks, coils, pond snails and others.
A riddle about a snail. Whose body consists of a head and legs in a shell?
Below on the site page you can see large and beautiful photos grape snails. To enlarge the photo, you need to click on the photo and the large photo will open in a new window.
Large beautiful photos of grape snails:
 |
| In the photo there is a prominent sedum and a grape snail |
 |
| The photo shows a beautiful grape snail |
 |
| In the photo there is a clever grape snail |
 |
| In the photo there is a drawing on the body of a snail |
 |
| The photo shows the head of a snail |
 |
| The photo shows a snail and a snail shell |
 |
| In the photo there is a close-up of a grape snail |
 |
| In the photo the snail unfolds on a leaf |
 |
| Pictured is a grape snail |
 |
| Pictured is a grape snail |
 |
| In the photo, a snail is looking for a way |
 |
| Pictured is a grape snail |
 |
| Pictured is a grape snail |
 |
| Pictured is a grape snail |
 |
| In the photo there is a grape snail from above |
 |
| The photo shows a grape snail on a leaf |
 |
| Pictured is a grape snail from behind |
 |
| In the photo, the snail's relative is the slug. |
Plan
Introduction
1 Description
1.1 Appearance
1.1.1 Sink
1.1.2 Leg and torso
1.1.3 Tentacles
1.2 Internal structure
2 Physiological features
2.1 Power
2.2 Breathing
2.3 Movement
2.4 suspended animation
2.5 Reproduction
3 Hatching
4 Natural enemies
5 Grape snail and man
5.1 Breeding
5.2 Application
5.2.1 In heraldry
5.2.2 In cooking
5.2.3 In culture
5.2.4 In medicine
5.3 Harm to agriculture
Bibliography
Grape snail
Introduction
Grape snail (lat. Helix pomatia; great snail, opercular snail, Burgundy snail, apple snail, Roman snail, moon snail, edible snail) is a terrestrial gastropod of the order of pulmonate snails of the family Helicidae.
It is believed that the homeland of the grape snail is Central and Southeastern Europe. Since ancient times, people have used grape snails as food, and they were not a delicacy, and people of any social status consumed them as an affordable and healthy food.
The species has settled in all but northern parts of Europe and on the coast Baltic Sea. It lives in thickets of bushes, on light forest edges, in gardens and parks. The snail is active from spring until the first cold weather, after which it burrows into the soil to a depth of 30 cm and falls into suspended animation. As a rule, it winters in the same shelters. During suspended animation, the mouth of the shell is closed with a calcareous plug - the epiphragm, the thickness of which depends on the severity of winter.
In nature, a grape snail lives on average 7-8 years, but can often live up to 20 years if it is not eaten by a predator. The registered record is 30 years, but in this case the individual was kept at home.
1. Description
1.1. Appearance
in the main picture h.aspersa, not h.p. The body, like that of all representatives of the class, is externally divided into a shell and a trunk. In the latter, the leg and head are distinguished. The internal organs are surrounded by a mantle, part of which protrudes from under the shell.
Sink
The diameter of the shell of an adult is on average 3-4.5 cm; its volume is sufficient to completely accommodate the entire body. The shell is spirally curved; has 4.5 turns lying in different planes (the so-called. turbospiral); twisted to the right; spins clockwise. Such shells are called dexiotropic.
The shell color varies from yellow-brown to brown-white. Along the entire length of the first 2-3 whorls there are 5 dark and 5 light stripes. The shell color of some individuals is darker, while others are lighter. This saturation depends on the habitat of the individual and is associated with the amount of solar radiation. The coloring is also related to the background of the environment, i.e., it is intended to camouflage from enemies. The color of the shell may change depending on what food the individual eats.
The shell is ribbed. This increases the surface area, allowing the accumulation of large quantity moisture. The ribs also give the sink greater strength and, in addition, thanks to them, the sink weighs less.
Leg and torso
The usual leg length of an adult is 3.5-5 cm, but the animal can stretch out greatly, up to 8-9 cm.
The body of the grape snail is very elastic. Its color varies among different individuals, as does the color of the shell. Usually the body color is beige with a brown tint, less often dark gray. It has its own special pattern. In some cases, snails lack such a pattern, or it is almost invisible, so the color of their legs is monochromatic. Body color can change in one individual when it eats different foods.
The body is completely covered with wrinkles, the areas between them look like quadrangles. Wrinkles increase the surface area of the leg and retain moisture.
Tentacles
There are two pairs of tentacles above the snail's mouth. The length of the anterior tentacles - labial - ranges from 2.5 to 4.5 mm. They have an olfactory function. The length of the rear tentacles - the eye ones - is from 1 to 2 cm. At the end of the latter there are eyes, all of whose receptors contain the same photopigment, which is the cause of color blindness of the animal. However, the eyes are able to distinguish not only the degree of light intensity, but also objects at a distance of up to 1 cm.
The tentacles are very mobile. The rear ones can be located relative to each other at an angle greater than the unfolded one. The front tentacles are less mobile, changing position only in the vertical direction, lowering and rising; usually form an obtuse angle with each other. Both pairs are very sensitive: if they accidentally touch an object, the tentacles instantly retract inward. The eye tentacles also react negatively to very bright light.
1.2. Internal structure
Like all representatives of the class, digestive system The snail is divided into an ectodermal foregut and an endodermal midgut. Breathing is pulmonary. The heart, located above the hindgut, consists of the left atrium and ventricle and is surrounded by the pericardium. Blood is colorless. Nervous system scattered nodular, consists of several ganglia. The excretory system consists of one kidney, one end communicating with the pericardium, and the other opening into the mantle cavity next to the anus. The reproductive system is hermaphrodite, cross-fertilization.
2. Physiological characteristics
2.1. Nutrition
The grape snail is herbivorous; feeds on both living vegetation and plant remains. Consumes grape and wild strawberry leaves, cabbage, horse sorrel, nettle, burdock, lungwort, dandelion, plantain, radish, horseradish. To grow a shell, the animal requires calcium salts. There are also cases of eating food of animal origin. During the first time, individuals emerging from eggs feed only on substances contained in the soil.
2.2. Breath
The grape snail breathes using its lungs. The breathing opening - the pneumostome - is located between the folds of the mantle, on the same side as the whorls of the shell.
IN normal conditions the breathing hole closes and opens approximately once a minute; with high air humidity it is less active. The increase in the number of openings and closings of the breathing hole is directly related to the increase in concentration carbon dioxide in the air.
2.3. Movement
The vine snail moves with the help of its muscular leg. With the help of muscle contractions, the animal, sliding, pushes off from the surface. When moving, mucus is secreted, which softens friction and facilitates movement along the substrate. The glands that secrete mucus are located in the front of the body. The average movement speed is about 1.5 mm per second.
2.4. Anabiosis
Anabiosis in a grape snail lasts up to 3 months. In the natural conditions of Belarus - at least 5 months, while mollusks with a period of suspended animation of less than 60 days under experimental conditions were further characterized by reduced fertility or did not produce eggs at all. She can settle both on a horizontal (for example, on the ground under a stone) and on a vertical ( on the walls of buildings, on the side glass of a molluscarium at home) surfaces.
With the lower part of the leg - the sole - the individual is attached to the substrate, after which it curls up inside the shell. Still holding on to the surface with the tip of its leg, the snail, with a film of mucus, covers the space between the surface of the substrate and the edges of the mouth of the shell, after which it removes the remaining part of the leg, covering the hole with folds of the mantle. The film freezes, turning into an epiphragm.
2.5. Reproduction
Grape snails mate in spring and early autumn. An individual seeking to mate can be easily detected by its behavior: it crawls as if looking for something, stops, and stretches out its body. Two snails, having thus found each other, proceed to the “love game” that immediately precedes copulation.
During the direct act of fertilization, individuals are pressed against each other with their soles. In both individuals with right side on the body, just below the oral cavity, elastic white outgrowths appear - the genitals. The latter constantly change shape: either they are sharply and quickly removed, or they gradually appear again. The breathing holes during intercourse are very widened and almost never close. The snails' heads are pressed against each other and are in a circular motion. As soon as the genital organs of the snails come into contact with each other, the former rapidly grow to enormous sizes. Individuals sometimes disperse into different sides. Following this, the mating process continues. On average, the act lasts about 2 hours.
Having reached the peak of their arousal, the snails connect the genitals. At this time, the exchange of male reproductive cells begins to occur. After a short period of time, the partners remove their genitals and separate.
3. Hatching
Grape snails hatch in the ground, at a depth of 5-10 cm. At the time of hatching, the diameter of the shell is 2-2.5 mm, while the diameter of the spherical egg is about 5-7 mm. The egg is soft, has white color. The snail, having fully formed, eats the remains of the egg shell and slowly begins to crawl upward. It reaches the surface in 8-10 days; all this time the snail feeds on the soil and the substances contained in it.
4. Natural enemies
Natural enemies of the grape snail are hedgehogs, shrews, lizards, moles and some other animals. Also natural enemies are different kinds crawling beetles that can crawl inside the snail through the breathing hole, and some types of predatory snails.
5. Grape snail and man
5.1. Breeding
Grape snails have been bred since ancient times. According to the testimony of Pliny the Elder, he was the first to breed them Fulvius Lippinus .
