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What does a water spider look like and whether it is dangerous for humans - interesting facts about silverfish, varieties

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Water spiders (Argyroneta aquatic) live underwater, they have their own "diving bell", which supplies them with oxygen. Essentially, they float to the surface of the water and then collect air bubbles to fill their “diving bells” underwater. They float to the surface once a day to get extra oxygen.

  1. 1 Know what a water spider is. Here are the key features:
    • physical characteristics: 0.314 "to 0.590" (8 to 15 mm)
    • Virulence: Yes
    • Lives: in Northern and Central Europe
    • Is eating: This spider catches its prey under water and kills it with a poisonous bite. It feeds on water insects and crustaceans.

Method 1 Determine a Water Spider

Both males and females are usually light or dark yellow-brown, but they are never on the surface of the water for too long, so you can cheat to look at them close.

  1. 1 Look at your stomach, if possible. When this spider is in the water, the stomach has a gleam of silver, like mercury.
  2. 2 Understand that if a spider dives from water to water or sits quietly on the leaves of a water lily or other vegetation, then it is most likely a water spider.
  3. 3 Look at the spotty green patterns, and sometimes green stripes on the back are visible.
  4. 4 Pay attention to the legs, they are long and thin.

Method 3 Bite Treatment

Water spiders are part of the family of funnel water spiders that are poisonous. But the bite of a water spider is likely to cause nothing but inflammation and heat. You probably won’t be bitten if you don’t put your hand in the water where they live. Water spiders have strong fangs that can penetrate the skin of a person, and a bite can be very painful. If you were bitten by a water spider, be sure to do the following:

  1. 1 Wash the area where you were bitten with warm water and soap.
  2. 2 Wash with soap and blot dry with a clean cloth.
  3. 3 Apply an antiseptic cream to the bite area.

Silver spider

Silver spider
Scientific classification
Kingdom:Eumetazoi
Infrastructure:Araneomorphic Spiders
Superfamily:Dictynoidea
Gender:Argyroneta Latreille, 1804
View:Silver spider
International scientific name

Argyroneta aquatica
(Clerck, 1757)

  • Araneus aquaticus
  • Aranea aquatica
  • Aranea urinatoria
  • Aranea amphibia
  • Clubiona fallax

Silver spider , or water spider (lat. Argyroneta aquatica) - a common European species of spiders from the family Cybaeidae. It features long swimming setae on the hind legs and 3 claws on the legs of 3 hind pairs.

The only species of spiders living in the aquatic environment.

Classification and habitat

The Latin name for the spider is Argyroneta aquatica. Belongs to the family Cybaeidae (cybeids).

Serebryanka live on most of the Eurasian continent - from the islands of Britain to Japan. In Russia and Europe, distributed in most regions. A water spider populates reservoirs with stagnant water, occasionally it chooses small rivers and streams for habitation.

In the reservoirs where the silver spider lives and breeds, there should be abundant vegetation, a lot of algae, on which he builds web networks for catching prey and breeding.

The Latin and Russian version of the name of the water spider contains the root "silver".

Being in water surrounded by air, the body of the animal shines with a silver sheen, therefore it is called in different languages ​​in accordance with this quality.

Nest

The male, which is larger than the female (this prevents the cannibalism of the female), reaches 15 mm in length, the female - up to 12, the almost bare cephalothorax is brownish, turning into blackish, with black lines and spots, the abdomen is brown, covered with many velvety hairs and has on the dorsal side two rows of indented points.

When silverfish are immersed in water, the abdominal hairs, covered with a special fatty substance, are not moistened, air is delayed between them (because it is not forced out due to the surface tension of the water) and therefore it appears silver under water (hence the name of the species). This layer of air allows the silverfish to remain under water for a long time, it occasionally rises to its surface in order to renew the supply of air. Water-repellent substance is a modified secret of spider glands. A water spider comes across in stagnant or slowly flowing waters quite often.

A water spider feeds on various small animals that get entangled in the threads of its underwater web, or which it catches while swimming in water. He sometimes hangs caught prey in his nest.

Socket [edit |

Wildlife behavior

If, according to the description, silverfish can be confused with other species of the arachnid class, then the lifestyle is fundamentally different. Dropsy is the only spider that lives perfectly in water. Swimming functions are provided by the legs with which he rakes, like oars.

You can’t consider silverfish an absolutely underwater spider - it runs perfectly on land. At the slightest danger, the animal pulled by the net to the surface develops an enviable speed.

Dropsy can be detected and identified by an air bubble (bell), in which it sits shallow under water, half leaning out, and expects a gaping victim.

The construction and maintenance of an underwater house is the main part of the life of silverfish, a condition for its successful hunting.

The construction of the nest takes place in several stages:

  1. First, silverfish chooses a convenient place for hunting - hangs loose web on underwater plants. Gossamers are a product of special glands that are found in all arachnids. This sticky substance comes out liquid, but quickly hardens in air and in water.
  2. By weaving a net, dropsy begins to draw air from the surface. It comes to the surface and captures air bubbles with the hairs on the body. Releases it under a spider web, lifting it.
  3. The spider web plays the role of a balloon shell. As a new portion of air is captured, the spider strengthens the surface with new layers of cobwebs. The atmospheric air captured by the hairs is what the silver spider gradually fills the nest with.
  4. The air rises the built dome, inside it forms a convenient nest the size of a walnut.

One end of the shelter - open, serves as the entrance to the underwater house. In the dwelling, the silverfish rests, cleans the hairs, waits for the victim, eats, hangs the prey left for the future.

The spider lives alone in the nest, males build dwellings close to the females, but lodge separately.

You have to fill the dome with air regularly. Healthy strong individuals have large nests. Sick and weakened silverfish lose their ability to hold air on their bodies, the nest falls apart, becomes small and loose. Spiders weaken and drown.

Types of Domes

For different life processes, water spiders build special nests:

  1. Summer. In these shelters, most of the active life of silverfish takes place.
  2. Egg Typically, females convert their housing into egg domes when laying.
  3. For molting. Here, spiders wait for a period of change in the body shell.
  4. Wintering. This shelter is designed for hibernation - the shell is dense, smaller in size. However, more often silver spiders use shells for wintering. They skillfully adapt to the conditions and occupy the empty houses of mollusks.
  5. Sperm. Males build to prepare for breeding.

Building a nest takes several hours. During this time, silverfish rises to the surface several tens of times - it stops for rest and continues to work until complete.

Breeding

The male searches for a female and fertilizes on its territory - in summer housing. She looks after posterity. In the clutch - from 15 to 160 eggs. The female regularly fills the bell with air, guards the masonry.

Egg development lasts 10 days. Little spiders molt twice in the mother’s house, then leave the house and live on their own.

Family ties after leaving the nest are broken. A starving female can eat gaping spiders from her own brood, who left the house.

Overwinter can be at any stage of development. Late clutches await the winter in the mother's nest. Spring ponds are usually full of young silver spiders.

Aquatic plants falling to the bottom in autumn pull nests with spiders down. There they spend the winter. In spring, they come up closer to the surface. Some winter on the shore in shells. With the onset of heat, they thaw safely if they are not eaten by birds.

Spring waters spread dropsy over a large area. They migrate in mollusk shells and right in the domes.

Body dimensions and structure

The appearance of dropsy is quite classic - the body consists of two parts. There is a deep section between the cephalothorax and abdomen.

The body of young spiders is painted in a lighter color (tan, greenish gray) than in adults and older.

Body structure features:

  1. The cephalothorax is round, the head is convex, slightly narrowed.
  2. There are 8 pairs of eyes, despite this weak vision, already in a few centimeters the silver spider does not distinguish objects.
  3. There are 2 pairs of jaws on the head, one of them with sharp edges (chelicerae) and a poisonous gland. With the help of the secret of this gland, a spider immobilizes and kills prey.
  4. On the legs there are hairs with which the spider palpates objects. They play the role of the organs of touch.
  5. The shield is similar in shape to a heart, under it are the bases of 4 pairs of legs. In males, the front legs are longer than the hind legs.
  6. The abdomen is not dissected. The surface is covered with bristles or hairs. Their density is very high - about 1000 per square millimeter. These hairs have different shapes and lengths. They serve to hold air around the body.

The structure and arrangement of hairs in males and females is different. The male has no hairs on the back. Because of this, the air dome of spiders is different, the shape of the bell around the body of a female can be distinguished from a male.

Although most silver spider lives in water, it breathes atmospheric air. Underwater existence is ensured by the construction of a cozy nest, similar to a vessel with air, and thin bristles that are not wetted by water.

Serebryanki constantly rub their hairs with their paws, cleaning them from pollution, so that they better retain air. To do this, they suck on the paws, while highlighting a special secret that processes the hairs on the body.

This is the main occupation of the spider in the air dome when it does not wait for prey.

The size of females of silverfish is 11-12 millimeters, males - 14-18 millimeters. Female dropsy are small, do not differ in aggressiveness. They do not eat their males after fertilization, like other spiders. Coexist safely in the neighborhood - males usually build a house near the nests of the females, so as not to look for a long time for a partner for breeding.

Varieties

The most common species in our country is Clubionafallax - dropsy, silverfish.

This species perfectly adapted to life in shallow still waters, it builds bell-shaped domes for itself and posterity. Each dwelling is intended for a certain phase of life - molting, wintering, breeding.

Males are 2-3 mm larger than females; they look identical in appearance, have a slightly darker body color.

Dolomedes

This species is a representative of surface spiders that run on the surface at high speed. They prefer the water surface to dry land, when in danger, they easily dive into the water. The body size of females reaches 22 millimeters, males are significantly smaller (13 millimeters).

Can live on the shore, where he drags the caught prey and eats. Shelters may not do, just hiding in the thickets of grass.

His lifestyle can be called semi-aquatic. It lives near water bodies, swamps, loves moist areas of meadows, forest thickets, penetrates gardens.

Dolomedes can feed on insects caught in the air, aquatic inhabitants - fry, crustaceans. Kills the victim very quickly, then relishes food for several hours.

What does it eat?

Like all arachnids, silverfish are predatory animals. They build traps for catching prey, which are located under water. The web serves to capture small animals, while the owner is waiting in the dome. According to the fluctuations of cobwebs, the silverfish determines the appearance of the victim.

Next, dropsy acts like all spiders - injects poison, then saliva. Waits for softening food and dines. If there is no desire to eat, the prey is carried away to the dome and hung in reserve on the web.

Underwater and terrestrial small inhabitants make up dropsy food. The prey of the female often becomes its own children, who have left the nest.

Small crustaceans

Silverfish spends most of its life in water. Small crustaceans are the usual spider diet. Water donkeys, small crustaceans of 1-2 millimeters in size are among your favorite types of food.

In the net of silverfish fry are also often caught, which can reduce the population of some fish species.

Mosquito larvae and insects themselves, in abundance living near water bodies, make up a significant part of the silverfish diet.

The ubiquitous flies of various species and their larvae often fall on the net and become the food of silver spiders.

How many lives?

Life expectancy of silverfish is usually about a year. Only individual individuals can live up to 18 months. Adult males rarely winter, usually only females, eggs and young animals.

With aging and disease, the spider loses its ability to hold air in the hairs. Bacteria multiply in its bristles, they stick together. Serebryanka cannot build and maintain an air dome. The nest decays, the spider perishes.

Is it dangerous to humans?

All spiders secrete poison, which serves to kill prey. This poison is dangerous only for small animals and insects.

With occasional brief contact, silverfish can bite a person. At the site of the bite, redness, a slight burning sensation often appears. The wound should be treated with an antiseptic, if necessary, apply cold.

Symptoms disappear within a day, no trace remains. If an allergic reaction occurs, it is worth taking an antihistamine.

Is it listed in the Red Book?

Some species of water spiders are listed in the Red Book. Serebryanka is a rare species, it is listed in the Red Book of many regions of Russia. In most European regions, it is practically not found, although it used to live wider.

Dropsy is more common in the Caucasus, Siberia, in the southern part of the Far East, on Sakhalin.

The silver spider is a wonderful animal to study and observe. Dropsy can be kept in aquariums (at least 5 liters) and monitor the construction of nests. Glass containers will reveal all the details of the life of an amazing creature.

In the aquarium, you need to place water plants, hard sticks that go to the surface. Silverfish is fed with bloodworms, water donkeys. It is better not to contain aquarium fish with a spider. The observer will have a great opportunity to see the construction of the funnel-shaped dome.

The female and the male coexist in the same container if the feed is in abundance, otherwise a more dexterous one will eat the weak.

Fans of arachnids often choose silverfish for a home terrarium (aquarium). This spider is characterized by unusual behavior for the Arachnida squad and habitat. Like all representatives of arachnids, silverfish benefit by destroying insects, larvae, weakened and sick small aquatic inhabitants.

Young individual

Hatching from eggs, young spiders remain in the cocoon for some time.

Barely born individuals have a gray or brownish-yellow color, which darkens over time.

Spiders spend 10 days in a cocoon, where they grow up and molt a little, then they scatter and start an independent life.

Adult

The body structure of the water spider is the same as the terrestrial species: consisting of the abdomen and cephalothorax body has a clear deep separation. On a smooth cephalothorax there are four pairs of visually impaired eyes and two pairs of jaws - chelicera (for grasping and mortification of prey) and pedipalps (act as tentacles).

The body of the water spider has the shape of a cylinder. The abdomen and all eight jointed legs are covered with bristles lubricated with the water-repellent secretion of the spider glands. Thanks to this feature, a silver air cocoon is created around the spider when immersed, allowing it not to rise to the surface of the water for a long time.

What the animal eats

Water spiders feed on insect larvae, small crustaceans, fry entangled in the underwater web. Having discovered the prey, the spider entangles it with a net and transfers it to its dome. Once in the home, the spider lies on its back. Its front paws rest against the wall of the dome, and the tentacles hold the victim so that it is in contact with the mouth of the spider. The prominent digestive juice softens the guts of the prey. The enzymes processed by the juice are absorbed by the spider, inedible residues are thrown out of the nest.

Hydrachna cruenta mull

This species is sometimes called a water tick, a red spider.

Arthropod lives in swampy reservoirs with warm stagnant water. The spider has the appearance of a small red ball, moves on the surface of the water quite quickly. It feeds on larvae and small crustaceans, but quite often it itself becomes the prey of predatory insects or fish.

Red spiders make masonry on the inner parts of the leaves of aquatic plants, connecting the eggs together with a sticky solution.

Juveniles are born with six legs. Первое время молодые особи паразитируют на жуках и клопах, присасываясь к ним хоботками, однако вскоре уходят в водные норы, где окукливаются и превращаются в полноценных паучков.

Dolomedes fimbriatus L

Паук-охотник. Этот вид живет не в воде, а рядом с ней или на ее поверхности.

Членистоногое имеет серо-бурую окраску с проходящей по бокам туловища белой или желтой полосой. Посредине туловища можно заметить два ряда светло-серых точек, грудная часть преимущественно окрашена в желтый цвет, брюшко же серое. Самка паука-охотника достигает в размерах 2,5 см, самец в несколько раз меньше.

The hunting spider is remarkable for the construction of rafts. Due to the lack of ability to move around the water surface, the arthropod collects leaves and sticks floating in the water and connects them with a web. Having discovered the prey, the spider quickly gets to it on its floating island, drags the victim onto the raft and eats there.

Females lay eggs on plants growing along the banks of the reservoir, encircle them with a cocoon from the web and guard until offspring appear.

Clubionafallax

Silver-spider (or dropsy) is the most common species of aquatic in Russia spiders. This population has adapted to exist under water, where spiders build several species of oxygen-filled domes with different purposes:

  • summer (for shelter, eating food and mating),
  • sperm (for semen collection),
  • egg (for laying eggs and offspring),
  • for molting,
  • wintering.

To fill the nest with air, the spider has to climb at least 80 times behind it.

Males have a gray-green or black shade and reach a size of 15 mm. Females are lighter and 2-3 mm smaller than their partners.

Benefit and harm

Water spiders benefit by destroying insects and their larvae: adult flying individuals falling into the water, mosquito larvae, etc. serve as food for arthropods. Often the fry become food for water spiders, but they are mostly weak from birth or defective individuals.

Spider bites can do little harm, as they are very painful.

Insects are different. If you want to learn about the most dangerous insects on Earth - read this article.

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Is a water spider bite dangerous?

Water spiders rarely attack first: they are not too aggressive. However, if a threat occurs, the spider may bite.

The bite of an arthropod does not pose a threat to life, but causes severe pain.

The wound left by the poisonous jaws first aches, then the pain spreads around it. Numbness may occur. As a rule, after a few days the pain disappears.

Some species of water spiders, such as silverfish, are considered endangered species and are listed in the Red Book, so even if such a spider has bitten you, do not harm it.

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