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The Brown Recluse spider is very small but very dangerous – its poison is so strong that without timely medical assistance it can lead to death, while the pain begins to be felt far from immediately, and it can bite a sleeping person. This dangerous creature often lives in abandoned buildings and even residential buildings.

Origin of the Species

The appearance of the first arachnids dates back to the Devonian period – however, these were not at all the same species that inhabit our planet now. Arachnids evolve rather quickly, as a result, old species are dying out, but not just like that, but changing and giving rise to new ones. The oldest arachnids became the first sea creatures to land on land, settled on it, and when other living creatures followed them, they began to lead a predatory lifestyle. The main difference from other living beings was their web, produced by special glands originating from one of the pairs of legs. It is by the use of the web that it is determined when the ancestors of the species of spiders occurred: among the simplest ones, it is used only to create cocoons, while the more developed ones find other uses for it, for example, they put nets or make nests. The Brown Recluse spider is one of those that use the web only for the cocoon.

But this does not mean that the species itself is ancient – like all other species of arachnids, it appeared not so long ago, within several tens of millions of years ago, it just changed relatively little in comparison with its ancient ancestors. In general, the evolution of spiders has been relatively little studied and further research is needed. Scientists have not yet established reliably the chain along which most of them developed, including Brown Recluse. It is only clear that the lifestyle of the Brown Recluse spider is similar to that of its distant ancestors – it is even possible that such a strong poison was necessary for him against some already extinct creatures, and therefore has survived to this day. This species was described in 1940 by V. Gerch and S. Mulayk. Received the scientific name Loxosceles reclusa, assigned to the family Sicariidae.

Appearance and Features

The dimensions of this spider are quite small: with legs up to 20 mm, and without them it is even 5-7 mm. Usually, the female is larger, but the difference is small. The body of the spider is covered with hairs, thick and short, in appearance they can be mistaken for fur. It also differs from most other spiders in that it has only 6 eyes, not 8. By this sign, you can recognize it: it is clearly visible that the spider has only one pair of eyes in the middle, and two more on the sides. Otherwise, it is not much different from some other spiders, which is why they are often confused.Brown Recluse: Species Profile 9

However, there is another important sign: on his cephalothorax, you can see a pattern that resembles a violin. But this picture is difficult to see, you need magnifying devices. Although these spiders are called Brown, in reality not all of them are like that, some are gray or dark yellow. Their web does not have a clear and ordered pattern, and it seems to be woven completely chaotically – in fact, it is so. The web is sticky to the touch. Paws are thin and long. The alarmed Recluse spider pulls in the front pair, rests on the back pair, and lifts the middle one up. So he warns that he is ready to defend himself, this pose is designed to scare off the aggressor.

Interesting fact: It was previously believed that giant spiders lived on Earth in ancient times, but relatively recently it turned out that a mistake was made in the reconstruction of the fossils, and in fact, they are not at all so large. The largest spider lives on our planet to this day – it is the Goliath Tarantula, its length is 28 centimeters.


The main habitat is the southeastern United States from Illinois and Nebraska to Texas and Virginia. In California, it can be found occasionally and only indoors. In the states located within the specified range, it is found quite often. In some places, even too often – sometimes there are real invasions of these spiders. They can be found outside the designated area, but much less often, only if they are accidentally brought in. It is able to live in various natural conditions so that even if during transportation it turns out to be in very distant lands, for example, in Europe, it successfully survives.

There is evidence that he took root in Africa and South America. In addition, in recent years it has been noticed quite often in Australia, it is possible that it has become entrenched on this continent as well. Until the habitat of these spiders outside North America has not yet been reliably established, information about them is fragmentary. He prefers a room as a habitat, it is best if it is warm and dry. At the same time, he was called a Recluse for a reason, but because he does not like company and prefers to settle in abandoned premises, or simply uninhabited, such as summer houses, basements, or attics.

It will not be an obstacle even if the room is unheated: the Brown Recluse is quite capable of surviving the very moderate winter cold inherent in its habitat zone. And yet he does not like the cold, and therefore in winter, living quarters can also move through doors or windows. He prefers to hide from people and live in secluded places: behind baseboards, furniture, radiators. It can also live at a distance from dwellings, in various shelters, for example, in a rock or under logs.

FoodBrown Recluse: Species Profile 10

It hunts exclusively on small insects that are inferior in size to itself, most often significantly. This is due to the fact that he does not set trapping nets, but hunts without them: he hunts down the prey, after which he attacks it and bites, injecting poison. Without the help of the network, it is difficult for him to cope with large prey – it can be dangerous. In his diet:

  • small midges;
  • mosquitoes;
  • mole;
  • small spiders, including fellow tribesmen;
  • and the like.

After the bite, the victim is immediately paralyzed, and she can no longer resist – and most often dies after a few moments since the poison in this spider is very strong. This method of hunting is still less effective than using a net, and therefore a Brown Recluse sometimes has to be left without food for a very long time. His body is accustomed to such a situation – he can store nutrients for future use for several weeks or even a month and a half in advance. He hunts at night, during the day he usually rests in secluded places – he does not like sunlight at all and tries to avoid it.

Interesting fact: Usually spider venom is poisonous to the extent necessary for food. So, if a spider feeds on insects the size of a fly, it is just enough to quickly immobilize it. The larger the prey a spider hunts, the stronger its venom.

But with this species everything is completely different: it hunts for very small animals, but its poison is extremely toxic even for humans. For researchers, it still remains a mystery for what reasons, in the course of evolution, he began to produce such a powerful poison.

Features of Temperament and Lifestyle

The spider always tries to dwell in solitude so as not to be disturbed. This means that even if he settled in an apartment, he cannot be found somewhere in a conspicuous place, except perhaps during a hunt.

During the hunt, the spider can move far from the nest, especially if it does not live indoors, but in nature. If there is little prey in the place where he lives, he may even move to another. But long walks on the hunt are characteristic primarily for males, they also roam more often, but for females it is much easier to climb and spend almost all the time in the nest, trying not to leave it.

Since he prefers to hide from people and is active at night, you can usually meet him exactly at night when he hunts – most often spiders bite people precisely because they disturb them, not noticing in the dark. A spider can show up in a shoe drawer or in a closet, and sometimes hunting can even take him to bed. If they do not encounter people, then they live quite a long time by the standards of spiders – on average 3-4 years, sometimes they can even reach the age of 6 years. During this time, the female manages to lay eggs many times, so if you leave the Brown Recluse alone, at some point you can find that there is already a whole family of them – therefore it is better to fight them right away, without waiting until there are a lot of them.

Social Structure and Reproduction

These spiders almost always live one at a time, however, the possibility of the formation of groups is not excluded. The reasons why these spiders, usually avoiding the society of congeners, sometimes begin to live in groups, moreover, in large ones, have not yet been reliably established. But one can only pity the owners of the premises in which such a group settled: it will be very difficult and dangerous to fight them, there are cases of real invasions, and for the owners, they sometimes ended very sadly, because these spiders are extremely poisonous.Brown Recluse: Species Profile 11

At the same time, spiders are usually not prone to attacks on people, and indeed on any creatures other than prey: they only bite if they think they have been attacked. The problem here is that due to the small size of the spider, people sometimes simply do not notice it – and also due to the fact that meetings often take place in the dark. For example, a spider can attack if you accidentally pinch its limb. In addition, females can be very aggressive if a person approaches their nest with a clutch – they can bite, even if he does not take any aggressive actions.

Reproduction can occur several times a year – after fertilization, the female lays eggs in a cocoon, several dozen, sometimes up to fifty. After that, it stays nearby all the time and protects the clutch, even practically ceases to hunt. After hatching, the spiders grow rapidly for the first time, and after about a month they begin to live separately. They reach gender maturity by about a year.

Natural Enemies of Brown Recluse Spiders

Although this is a very poisonous and dangerous predator, there are also larger, more agile opponents who are not afraid of its poison, who already feed on it. These include:

  • centipedes;
  • crickets;
  • geckos;
  • wolf spiders;
  • and some others.

When living in nature, the spider is threatened by many dangers, which is why, despite effective reproduction, the population of Brown Recluse spiders remains quite stable – a very large number of them are exterminated by predators. This is especially true for young spiders, it is much easier for predators to hunt them than on those who have already gained experience, who have learned to hide and defend themselves, and have become very dangerous adult Recluse spiders. After all, an unsuccessful hunt for such a poisonous spider can end in the death of the hunter himself!Brown Recluse: Species Profile 12

But in apartments, there are much fewer threats to them, because in them these spiders can reproduce quickly. Other spiders become the most terrible enemy in them, because although a Recluse spider is dangerous for humans, by the standards of many other spiders it is relatively small in size, inferior in dexterity and strength. Since these spiders are very dangerous, they are often purposefully fought with, using poisonous substances to remove them from houses or utility rooms. Removing them from homes in the US states that are part of the range of these spiders is one of the main activities of pest control specialists.

Interesting fact: In the United States, about 7,000 people suffer from bites of this spider every year. Its poison is very dangerous, while at first, the bite may seem insignificant – usually, there is almost no pain from it, and it is comparable to a mosquito. It starts to hurt after 3-4 hours, and more severe consequences occur after 7-8 hours.