There are many kinds of spiders. There are 35,000 known spider species in the world, and new species are still being discovered. Do you know what is the smallest spider in the world? I will take you into the world of spiders.

The smallest spider in the world is a display spider. Biologists once collected an adult male display spider in Western Samoa, with a body length of only 0.043 cm, which is not as large as the printed period.

Spider; Spider-like objects; Star wheel; Cross; Connecting handle; crosshead

Araneae, an order of Arachnida. There are 350,000 known spider species in the world, and about 1000 recorded in China.

Body length varies from 0.5 mm to 9 cm. The body is divided into chest and abdomen. There is a carapace behind the head and chest, and there are usually 8 single pieces at the front end of the carapace, arranged in 2 ~ 4 rows. There is a big chest plate on the ventral surface and a lower lip in the middle of the chest plate. Abdominal knotless abdominal stalk evolved from abdominal node 1 The abdomen is mostly round or oval, and some have various strange-shaped protrusions. The ventral rotator evolved from appendages, and there are 8 primitive species, which are located slightly in the front; Most kinds of hexagyrators are located in front of the rear end of the machine body. There are many spinning tubes on the spinning machine, which are connected with various silk glands and spin silk from the spinning tubes. Sensory organs include eyes, various sensory hairs, suture sensory organs and tarsal organs.

Spiders mainly prey on small insects. Stealing spiders near the water can prey on small fish and shrimp, bird-catching spiders can catch birds, and a 7.5-cm-long spider in South America can even prey on small rattlesnakes. Web spiders prey on their webs. The female spider spins silk to form an egg bag, which contains fertilized eggs. Egg bags are attached to the net, or produced under rocks or leaves. Some female spiders guard egg bags, and some carry them with them. The young spider that hatched the eggshell stayed in the egg bag for a few days and peeled 1 ~ 2 times in the bag. Young spiders molt 4 ~ 15 times before maturity. Spider silk plays an important role in spider's life. Weaving webs is the instinct of many kinds of spiders. There are many kinds of nets, and the methods of weaving them are different. Many kinds of spiders, especially young spiders, can fly with silk.

Araneae is divided into three suborders: ① Araneae has more than 20 species in 2 families. ② There are about 14 families and 1500 species of protospiders. ③ There are about 90 families and more than 30,000 species of new Araneae.

Spiders are natural enemies of many agricultural pests. Spiders can be used as medicine to treat diseases such as proctoptosis, sores and bromhidrosis. The protection and utilization of spiders has become an important part of biological control. The venom of a few spiders, such as the black widow spider, is harmful to people and animals. Tarantula, a burrowing tarantula of the Tarantula family, is distributed in Europe and Asia and is common in Xinjiang, China. Its venom can kill people and animals. Some species of brown spiders have hemolytic venom, which will lead to regional necrosis and ulceration of wound tissue and expand the surrounding toolbox.

There are many kinds of spiders. There are more than 40,000 kinds of spiders in nature. These spiders can be roughly divided into three types: safari spiders, cobwebs spiders and cave spiders. The first kind will forage everywhere, and the second kind will wait for rabbits after weaving a net. Most people keep the third kind as pets: cave spiders. They like to hide in sand or holes and make a net at the hole. The net itself is not sticky, and it is purely used to sense the size of prey and hunt.

Spider habits

* * * A * * resin solution:

When spiders hunt, they paralyze each other with their fangs, secrete saliva to dissolve their prey, and then suck it slowly, without leaking at all.

* * * Two * * homemade fresh-keeping bags:

Spiders are afraid of light and often make webs where there is light and wind. Spider silk can be used not only to trap prey, but also as a fresh-keeping bag. The spider wrapped the leftover food in a net for the next time.

* * * three * * * cleanliness:

Spiders clearly divide the places where they eat, sleep and pull things. Domestic spiders generally use cages as garbage stations, urinate in them and throw food scraps.

* * * four * * appetite is very delicate:

Spiders have a strong sense of territory and should be kept separately. They only eat one or two meals a month and can fast for two months at most. The food is mainly insects, such as crickets and Cao Meng. As long as you put a wet sponge in the cage to replenish water, you can keep it for about seven years without changing the cage.

All spiders are poisonous! Only the toxicity is different. Usually, the toxicity of pet spiders in the market is relatively weak, and they will not take the initiative to attack people as long as they are not intentionally teased. Even if you are bitten, there is no danger to your life. Strong adaptability, no need for careful care. Spiders are the easiest pets to keep.

Function of spider silk

It can be used to make high-strength materials, and experts from the Institute of Gene Biology of the Russian Academy of Sciences are actively studying the use of spider silk to make high-strength materials. There is a rotator behind the spider's abdomen, which is filled with rotator glands. Protein mucus secreted by this gland can condense into extremely strong Jilin silk in the air. According to the Moscow Communist Youth League newspaper, experts from the Institute of Gene Biology of the Russian Academy of Sciences found that the hardness of this material is nine times higher than that of steel with the same thickness, and the elasticity is twice as high as that of other most elastic synthetic materials. Experts believe that after further processing, the silk raw materials in Jilin Province can be used to manufacture light body armor, protective materials for weapons and equipment, wheel tires, plastic surgery appliances, high-strength fishing nets and so on.

The largest spider in the world

It is a "bird-eating" spider in South America. It is said that this kind of "bird-eating" spider was found in the suburbs of Shanghai. A worker said that he had seen a bird-eating spider the size of a fist twice while fishing. Because of its strange and amazing shape, he dare not touch it easily.