Description and Features
Spiders are very interesting representatives of the biological kingdom, and some of them are far from harmless. They also have an amazing structure. Some varieties of these creatures have special appendages in their mouth, the so-called jaw claws.
These include araneomorphic spiders - members of a large group from the class of arachnids. The natural adaptations mentioned are called chelicerae. They allow these creatures to successfully attack prey quite large in comparison with their size, which gives them the opportunity to win in the evolutionary race.
It refers to such creatures spider cross - A bright copy from the family of orbiting.
This creature earned its name not by chance, but because of a very noticeable feature - the mark on the upper side of the body in the shape of a cross, composed of white, in some cases light brown spots.
A similar feature of the appearance is very useful for these biological organisms. This gift of nature is a sign that can scare away many hostile living creatures from them. The remaining characteristic features are clearly visible on cross spider photo.
As you can see, it has a rounded body. It turns out to be practically one with the head, being divided into two areas, which are commonly called the cephalothorax and abdomen.
The magnitude of such living creatures cannot be considered too large. For example, females, which are more impressive in size than males, are usually not larger than 26 mm, but specimens of such spiders are found only centimeter and much shorter.
Besides, a cross endowed with eight sensitive flexible legs. He also has four, and paired, eyes. These organs are located diversely, which allows this animal to have a circular view in all directions. However, these biological organisms cannot boast of particularly sharp colorful vision.
They distinguish only the outlines of objects and objects in the form of shadows. But the taste and smell are very good. And the hairs covering their body and legs perfectly capture a variety of vibrations and vibrations.
The cover of the body and at the same time, a kind of skeleton for these creatures is chitin - a special natural binder. From time to time, it is dumped by these arachnids, being replaced by another natural carapace, and in such periods the body grows, freed for a while from the elements that bind it.
This representative of the biological kingdom of arachnids is able to secrete a substance that is toxic to all types of organisms. So spider cross poisonous or not? No doubt this small creature is dangerous for many living things, especially invertebrates.
And the poison secreted by them is extremely detrimental to their neuromuscular organization.
Types of spider cross
The number of species of such spiders is impressive, but of the arachnids known to science, about 620 species are described in the family of crosses. Their representatives live all over the world, but still prefer to settle more in the temperate and tropical zones, because they can not stand too cold a climate.
Present in more detail some varieties.
1. An ordinary cross. This species is considered the most common. A similar living creature lives among shrubbery, on meadows, fields, and in the coniferous forests of the European as well as the northern part of the American continent.
They prefer wet areas, take root well in marshy areas, near rivers and other bodies of water. Their body is reliably protected by a strong thick carapace, and the moisture retains a special waxy coating on it.
Decorated with such white spider cross on a general brown background with a pattern. Such a complex pattern upon careful examination may seem very interesting.
2. The angular cross is a rare variety, and in the Baltic regions it is generally considered endangered. Interestingly, such arthropods, although they belong to the genus of the crosses, do not have a characteristic sign on the body.
Instead of this feature, on the abdomen of creatures covered with light hairs, two small humps stand out.
3. The innocent spider is an inhabitant of North America. The hunting nets of these creatures, which are sometimes significant in size, can be found in abandoned mines, grottoes and rocks, as well as near human housing.
The color of these creatures is dark brown. Through a similar coloring, they are masked against the background of their surroundings. The legs of such spiders are striped and covered with white shade of hairs.
4. Cat-like spider - another inhabitant of the regions of America similar to the previously described species. His body is also covered with a pile, and the hairs can be both light and dark. This is a very small creature. Some specimens may be less than 6 mm.
But if it is big spider cross of this type, it is probably a female, because their size can reach up to 2.5 cm. These arachnids got their name for a very interesting pattern on the abdomen, vaguely reminiscent of a cat's face.
This decoration of these creatures is located at the place where the relatives usually show off a cross.
5. Spider Prings is a small-sized resident of Asia, also common in Australia. Very interesting coloring has such a cross: black his abdomen is marked by a funny white pattern, while the cephalothorax and legs of such spiders are green to the color of the rich vegetation of the edges where such creatures live. The sizes of males in some cases are so small that they do not exceed 3 mm.
Lifestyle & Habitat
For settlement, these representatives of the animal world prefer to choose areas where there is no lack of moisture. These creatures are able to catch the eye wherever there is an opportunity to weave a web.
It is especially convenient for such creatures to arrange such a skillful hunting net between the branches, and at the same time finding shelter nearby, among the foliage of small shrubs or tall trees.
Therefore, spiders take root well in the forests, in quiet, unclimbed sections of gardens and parks. Their webs can also be found in various corners of neglected buildings: in attics, between doorways, window frames and other similar places.
On the abdomen of such creatures there are special glands, which in excess produce a substance for the person that allows them to weave hunting nets. They are known to be called cobwebs. From the point of view of chemistry, the natural building block for them is a compound that should be considered very close in composition to soft silk, which indicates its relative strength.
Patterned weaving, formed from the specified, first liquid and viscous, material with its further hardening, spiders usually weave with endless persistent tenacity. And after one or two days they destroy the old, worn out network, and weave a new one.
This construction can be called a true work of weaving art, formed from threads, the total length of which is 20 m.It has the correct geometric structure, being endowed with a strictly defined number of spiral turns with specific radii and distances from one network circle to another.
And this cannot but lead to admiration, for it causes aesthetic pleasure. But the perfect lines to create spiders are not helped at all by sight, they are guided by sensitive organs of touch.
These interesting structures are woven by these curious representatives of the biological kingdom, usually at night. And all this is extremely expedient and correct, because at the indicated time of the day most of the enemies of spiders indulge in rest, and no one bothers them with doing their favorite thing.
In such a lesson, they do not need helpers, and therefore spiders are individualistic in life. And do not spend much time communicating with relatives. Thus creating a hunting net, they crawl into an ambush and begin to wait for their prey, as always, in complete solitude.
Sometimes they do not hide especially, but are located in the very center of the web they have woven. Or a guard, sitting, on the so-called signal string, allowing them to feel all the connections of this weaving.
Sooner or later, some victim falls into the trap of a spider. Most often these are mosquitoes, flies or other flying small insects. They are easily entangled in the network, especially since its threads are sticky. And the owner of Putin instantly feels their trembling, as he is able to well capture even the most minor vibrations.
Further, the production is killed. Cross spider bite for such small creatures, it is certainly deadly, and the victim has no chance of salvation when he launches his poisonous chelicera.
Interestingly, small insects themselves can also be dangerous for spiders. Indeed, certain species of flies and wasps, taking advantage of their usual immobility, are quite capable in the blink of an eye to settle on the back of eight-legged predators and lay their eggs in their body.
In this case, the spiders are helpless, they are omnipotent only when their victim is stuck in the web. Spiders themselves cannot get confused in their hunting network, because they only move strictly in certain, radial, non-sticky areas.
The living creatures described are carnivores. In addition to the already mentioned flies and mosquitoes, their aphids can be aphids, various vultures and other small representatives of the world insect. If such a victim fell into the network of this predator, then he has the opportunity to enjoy it right away.
But, if he is full, he is able to leave food for later, entangled with a thin sticky thread. By the way, the composition of such a “rope” is somewhat different than a web thread. Further, the spider hides its food supply in any secluded place, for example, in foliage. And he eats it when he again feels hunger.
The appetite of such spiders is very excellent. And their bodies need a lot of food. The daily rate is so great that it is approximately equal to their own weight. Such needs force the described representatives of the animal world to work accordingly.
The crosses, waiting for their prey, are ambushed with virtually no rest, but even if they are distracted from business, then for a very short time.
In an extremely interesting way, these creatures digest their food. This happens not inside the body, but outside. Just in the body of the victim, wrapped in a cocoon, a portion of digestive juice is released by the spider. In this way, it is processed, turning into a substance suitable for consumption. Further, this nutrient solution is simply drunk by a spider.
It happens that in the network arranged by these eight-legged creatures, the prey is too large, which such a baby is simply not able to cope with. The spider strives to get rid of such problems by deliberately breaking off the network threads that are connected to it.
But if the threat does not stop there, in order to protect himself, he is quite capable of successfully using his chelicera against huge creatures, from his point of view. For example, a frog a quarter of an hour after its bite can be completely immobilized.
But for humans, spiders are dangerous or not? Actually, the poison of these creatures does not produce irreversible changes on the body of all vertebrates. On people, due to the small amount released by these arachnids, toxic substances in comparison with human size, they are not able to act in a serious way. A bitten subject feels only mild pain, which passes rather quickly.
Reproduction and longevity
The life of these creatures takes place on the web. Here, for them, begins the process of reproduction of their own kind. And the time for him is usually the end of autumn. At first spider male cross finds a suitable partner.
He then attaches his thread somewhere on the lower edge of its web. This is a signal that the female immediately feels. She feels special fluctuations of weaving and understands perfectly well from them that this is not someone, but the mating applicant violated her loneliness.
Then she goes down to her stall, than responds to his tokens. After intercourse, males do not remain alive. But the female continues the work begun. She creates a special spider web cocoon and lays her eggs there.
She first drags this house for posterity, but when she finds a suitable place for it, she hangs it on a makeshift thread. Soon cubs appear there, but they do not leave their house, but remain in it for the whole winter. They leave the cocoon only in the spring. But until warm times, their mother did not survive.
Young spiders grow, live the entire warm period, and then the entire reproduction cycle is repeated again. From here it is easy to understand: how many spiders live crosses. The entire period of their existence, even if taken together with wintering, is less than a year.