Leeches - annelids, leading a parasitic lifestyle. Most of the species, and there are about 500 of them, prefer to live in fresh water, but there are also representatives of marine biotopes. In our country there are 62 species.
In previous centuries, leeches were widely used to cleanse human blood. However, in the last century there was a peak of popularity on these worms, as a result of which their collection and intensive destruction of the natural range of leeches led to a reduction in their numbers. Today, the propagation of worms for medical purposes is carried out in specialized laboratories.
Characteristics
The body of the leech has a ring-shaped appearance, but slightly flattened than that of worms. And the stomach is a modified middle intestine. Most species of these worms have eyes, but all have a closed circulatory system.
Each individual has two suction cups:
- back;
- front
Using these suction cups, the worm is attached to the victim, as well as to surrounding objects. With their help, the leech moves.
Diet
What do leeches eat in nature? In most cases, leeches feed on the blood of mollusks, vertebrates and other representatives of the animal world. It is these types (not all) that are used for medical purposes.
Medical leeches have three jaw plates, on which a huge number of small and very sharp teeth. The jaws themselves are an accumulation of thick muscles. At the beginning, a leech pierces the skin with teeth, then tears the tissue and sucks the blood. After a bite, a protein substance called hirudin is released from the sebaceous glands of the worm sucker. It does not allow blood to coagulate, but on the contrary, provokes its flow to the wound. In addition, saliva with anesthetic properties is released, so the worm manages to go unnoticed for a long time.
Proboscis Leeches
One of the representatives of this subspecies is a fish leech, which swims beautifully, unlike a medical leech. What do leeches of this species eat? Tissue fluid of fish.
These are quite large worms and can reach 50 centimeters in length. They do not disdain almost any type of fish, on one you can find more than 100 worms.
When a leech does not eat, it swims calmly in a pond or "sits" on aquatic plants. For a person, it does not carry any danger. In winter, these worms do not hibernate, and without fish can live up to 3 months.
The habitat - Eurasia, lakes and large rivers, is very rare, but is found in wastewater. Prefers fish from the genus of cyprinids.
By the way, this worm can appear in the aquarium. What do leeches eat in such cases? All the same tissue fluid. It is quite difficult to cope with such a problem in a closed reservoir, most likely, complete disinfection and disinfection will be required. They can get into the aquarium with live food.
The cochlear leech also belongs to the proboscis annelids. This is a very slow creature that does not even move independently, but completely relies on the current. What do leeches eat? Mostly blood of pulmonary freshwater mollusks, and these are, first of all, prudoviks. After the attack of the worm, as a rule, the snail dies, since the leech causes airway obstruction. Worms also get into the aquarium with live food.
The closest relatives of these species are bird leeches - species that “feast on” the blood of Kamchatka crab and shrimp.
Horseleech
These worms are also called Nile or Egyptian. They live in Central Asia and the Mediterranean, in Transcaucasia. They prefer fresh water bodies of small size.
What do leeches eat in the pond? The equestrian species also prefers blood, but does not have a developed jaw, therefore it is attached to the mucous membranes of the victim when it bathes in a pond. Most often, horses become victims, but the worm does not disdain other artiodactyls, amphibians, and even representatives of the human race. They can even stick to the conjunctiva of the eye. The most dangerous thing about these worms is that, once they enter the body, they increase in size and if they get through the mouth, they can cause obstruction of the airways and, as a result, asphyxiation.
Predatory leeches
The most common species in Asia and Europe is the small Lozhkonsky leech. What do leeches eat in bodies of water with stagnant water? Oddly enough, but they use invertebrate representatives of the animal world. These are insect larvae - microscopic worms. The very small Lozhnokonskaya leech extends to a maximum of 6 centimeters in length, and itself can become a victim of a fish or invertebrate predator.
The leech of erpobella is doing the same. It is quite large and can be seen from afar. This is a wonderful swimmer, but the worm does not have a proboscis, but the body is equipped with a powerful mouth. What do leeches eat? All the same invertebrates, these are mollusks and fish fry, crustaceans, insect larvae. This worm does not disdain even carrion.
