Proudhovik Ordinary: description, food, enemies and habitat

In Russia and Europe there are different types of pond water. Among them, the largest is the ordinary pond snake, whose shell can reach 7 centimeters. All species breathe with light, therefore, from time to time they are forced to float to the surface. Often one can observe how the snail's pond snake, the photo of which is presented in this article, slides smoothly and slowly along the bottom of the surface water film, taking oxygen from the air.

If the mollusks, "suspended" in this way, somehow disturb, they immediately release a bubble of air from the breathing hole and fall to the bottom of the stone. Prudovik eared - this is the nearest relative of the ordinary. Its shell reaches 2.5 centimeters, which depends on the abundance of food and the temperature in its pond.

Proudhovician and other species of his family (except for the above, in our reservoirs can be found ovoid, small and marsh) are very variable. Variations in this form, size, thickness of the shell, color of the trunk and legs of snails. Along with those that have a strong shell, there are species with a very fragile, thin shell that breaks even with the slightest pressing. There may also be different shapes of the curl and the mouth. The color of the body and legs varies from sandy-yellow to blue-black.

Structure

The body of the mollusk is enclosed in a spirally wound conch shell, which has a mouth (a large hole) and a sharp top. The shell of an ordinary pond is covered with a layer of lime horn-like greenish-brown substance. She is a reliable protection of his soft body.

In the body of the cochlea, three main parts can be distinguished: the leg, the head and the trunk - although there are no sharp boundaries between them. Only the front part of the trunk, the leg and the head can protrude from the shell through the mouth. The leg is very muscular. It occupies the abdominal part of the body. Such snails are called gastropods. At the same time, sliding on the objects of the sole of the foot or hanging to the bottom film of water, the mollusc moves smoothly forward.

The trunk at the same time copies the shape of the shell, adjoining it very closely. It is in the front part covered by a mantle (a special fold). The space between it and the body is called the mantle cavity. The body in front passes into the head, which has a mouth on its underside, and two sensitive tentacles - on the sides. Prudovik, with a light touch to them, instantly draws the leg and head into the shell. Near the bases of the tentacles is located one eye.

Circulation

Prudovik ordinary structure has quite interesting. So, he has a heart that pushes blood into the blood vessels. In this case, large vessels are divided into small ones. And from them already the blood goes to the intervals available between the organs. Such a system was called "non-closed". Interestingly, the blood is washed by each of the organs. Then she again gathers in the vessels that lead to the lung, and then goes directly to the heart. In such a system, the movement of blood is much more complicated than in a closed one, because it slows down between organs.

Breath

Despite the fact that the snail lives in water, it breathes atmospheric air. For this, the ordinary pond snake, the structure of which is described in this article, floats to the surface of the reservoir and opens the breathing round hole at the edge of the shell. It leads to the lung - a special pocket of the mantle. The walls of the lung are densely packed with blood vessels. At this point, carbon dioxide is released and oxygen is enriched with blood.

Nervous system

This mollusc has an okologlotochnoe concentration of nerve nodes. From them, nerves go to all organs.

Food

The mouth of the cochlea leads to the pharynx. There is a muscular tongue covered with denticles - the so-called grater. The ordinary pond, whose photo can be viewed in this article, it scrapes the plaque from all sorts of microorganisms that are formed on various underwater objects, and also rubs different parts of plants. Food from the pharynx goes to the stomach, and then into the intestines. Liver also contributes to its digestion. The intestine opens with an anal opening into the mantle cavity.

Movement

If you catch a pond snail in a jar, it immediately starts actively crawling along its walls. From the opening of the shell, a wide leg extends, which serves for crawling, as well as a head with two long tentacles. Sticking the sole of the foot to various objects, the snail slides forward. In this case, sliding is achieved by wave-like, smooth contractions of the musculature, which can easily be observed through the glass of the vessel. It is interesting that an ordinary pond snake can wander along the bottom surface of the water, as we mentioned above. At the same time, it leaves a thin band of mucus. It stretches across the surface of the water. There is an opinion that snails moving in this way use the surface tension of the liquid, from below hanging to the elastic film, which is formed on the surface due to this tension.

This crawl can be easily observed on the calm surface of the reservoir, going on an excursion or relaxing in nature.

If the mollusk pond, which crawls in this way, under a slight pressure again plunges into the water, you will see how it again, like a cork, rises to the surface. This phenomenon is easily explained: there is air inside the respiratory cavity. He maintains the snail as a swim bladder. Prudovik can compress his respiratory cavity at will. In this case, the mollusc becomes heavier, therefore, it sinks to the very bottom. But with the expansion of the cavity, it floats to the surface along a vertical line without any push.

Try the pond snorkel floating on the surface of the pond, immerse it in water and disturb its soft body with a touch of tweezers or a stick. The leg will immediately be drawn back into the shell, and air bubbles will escape through the breathing hole. Further, the mollusc will fall to the bottom and will not be able to rise to the surface on its own in any other way, other than climbing the plants, due to the loss of the air float.

Reproduction

The mollusc is a hermaphrodite, although it has a cross fertilization. The snail lays eggs, which are enclosed in mucous transparent cords, attached to algae. From the eggs appear small pond with a very thin shell.

The content of the pond

Some aquarists allow the maintenance of pond water in one common vessel, not realizing that often this is simply unacceptable. After all, if, say, ampullaria is grown mainly in artificial conditions (in an aquarium), the snail is placed there directly from a pond, a small lake or a standing pond. Prudoviki, which were caught in natural conditions, are more likely to serve as a source of infectious diseases and parasites of fish. Very often young aquarists are offered to buy shellfish in the poultry market and in various pet stores.

If you decide to start an ordinary pond snake, you need to understand that a water temperature of about 22 ° C and its moderate stiffness is considered a prerequisite for its content.