Horned spider, or spiked orb-web spider. Species composition of orb weaving spiders

Class Cheliceraceae
Spider-cross (Araneue er.)
The cross-web spider is a member of the large family of orb-weaving spiders. These spiders weave an amazingly beautiful round web, with which they catch their victims. The spider-cross hunts mainly on flying insects, primarily Diptera and butterflies, helping to clean gardens and forests from pests.
DESCRIPTION
Females, which are significantly larger than males, can reach three centimeters in length. The color of the body of the spider is dominated by brown tones, two zigzag dark lines stand out on the abdomen, converging in the back. The legs are covered with light and dark rings.
■ HABITAT
This genus is widely distributed throughout the world. These spiders prefer high vegetation and hang their webs about a meter above the ground.

NOTES
In Japan, this spider is called "onigumo", which means "monster spider". He owes this nickname to his dark hairy torso and boundless gluttony. Its venom, which is deadly to ordinary spider victims, does not pose a serious danger to humans.

Orb weaving spiders
Spiders are invertebrates and are included in large group arthropods. The body structure and high adaptability allowed them to survive on Earth for millions of years. The order of spiders includes more than 20 thousand species distributed throughout the globe. Of these, more than 2500 species belong to the family of orb-weaving spiders. Many of these species are known under the common
called "garden spiders".

CLASSIFICATION

TYPE Arthropods
Subtype: Cheliceraceae
Class: Arachnids
Order: Spiders

Suborder: Higher spiders
Family: Orb-weaving spiders

The orb-weaving spider family includes spiders of various sizes and colors. The photo shows a representative of the species Argiope bruennichi

deceptive appearance
Representatives of the family of orb-weaving spiders are characterized by a large abdomen and a relatively soft external chitinous skeleton. However, despite the vulnerable appearance, spiders are ruthless hunters, and their poisonous chelicerae are terrible weapons.
The body of the spider is formed by two easily distinguishable sections. The anterior is called the prosoma, or cephalothorax. This department bears six pairs of limbs: two front pairs in the mouth (chelicerae and pedipalps), and the remaining four pairs - walking legs. The back of a spider's body is called the opisthosoma, or abdomen. High elasticity external skeleton allows the abdomen to vary greatly in size. After a hearty meal or before laying eggs, it can double its normal state.
Somewhat harder to see with the naked eye are two morphological features that distinguish spiders from other arthropods: chelicerae and spider warts. Chelicerae are located in front of the mouth and are two hooks with poisonous glands inside. Spider warts are located below the abdomen in front of the anus. A silk thread stands out from them, from which spiders spin their surprisingly complex and beautiful web.
1 - heart. In a spider, the heart is a tube with 3-4 pairs of ostia (slit-like holes), from the front end of which the aorta departs, dividing into two arteries. Of these, the hemolymph flows directly into the body of the spider, and through the ostia enters again into the heart.
2 - Stretched digestive system crosses the entire body of the spider and is represented by the mouth, oral cavity and intestines. The anterior part of the intestine expands into a muscular pharynx, which serves as a pump that draws in semi-liquid food. The midgut forms protrusions that increase the capacity of the intestine.


The brain consists of two sections: the anterior, which innervates the eye, and the posterior, which innervates the chelicerae. Spiders have no middle section, since they do not have antennae or antennae.
3 - The brain consists of two sections: the anterior, which innervates the eye, and the posterior, which innervates the chelicerae. Spiders have no middle section, since they do not have antennae or antennae.
4 - Poisonous glands are placed in chelicerae, and also protrude into the cavity of the cephalothorax. They produce poison with which spiders kill their victims.
5 - excretory system. It is represented by malpighian vessels, which have the form of two blindly closed branching tubules that flow into the intestine at the border of the middle and hindgut
6 - Spider warts. These are modified abdominal legs. At the ends of the warts there are arachnoid tubes, from which the cobweb is secreted.
7 - Ovaries. Organs in which eggs develop. In a pregnant female, the ovaries can occupy a significant part of the abdomen.
8 - Subpharyngeal nerve node
9 - Located under the esophagus and connected to the brain. Is a part nervous system: the nerve chain merged into the cephalothoracic ganglion. Nerve endings come out of it, going to various parts of the body.

1 - The cephalothorax. This section is protected by a special kind of dorsal shield, harder than the rest of the body of the spider. It covers vital organs, including honey.
2 - Abdomen. This is the most most of the body of the spider, covered with an elastic exoskeleton, allowing them to change in size. A characteristic pattern is often present on the back of the spider to aid in species identification.
3 - Walking legs. The spider has four pairs of walking legs. Each leg is formed by seven segments of various lengths. The last of them is called the paw and ends with two small claws. The size of the legs varies greatly in different species depending on the lifestyle.
4 - Pedipalps. They are shorter than the legs and are located in the anterior part of the cephalothorax next to the chelicerae. Formed by six segments and have sensory functions. In males, the last segment serves as a copulatory organ.
5 - simple eyes. Spiders usually have eight simple eyes. With the help of web spiders, they mainly distinguish between the strength and direction of light; wandering spiders have better vision. In general, the vision of spiders is poorly developed.
6 - Chelicerae. These are the oral appendages responsible for nutrition. They are equipped with a sharp sting connected to poisonous glands.

Netting
Spider warts are modified abdominal appendages from which the web is released.

Warts can be formed different amount segments, but the last of them is necessarily located a large number of cobweb-secreting organs, the so-called fusuls, forming concentric circles. The shape, size, and location of arachnoid warts vary between species.

HABITAT
In forests and gardens
The habitat of orb-web spiders is tied to the habitat of flying insects, which form the basis of their diet. Forests, shrubs and urban gardens suit spiders best: the abundance of flowers attract insects here, providing the spiders with the necessary amount of food.


The family of orb-weaving spiders is widespread on our planet and includes 2500 species. Its representatives inhabit almost all corners of the land: from sea ​​coasts up to six thousand meters above sea level. Without a doubt, it was the geographical distribution that determined the diversity of species of the family of orb-weaving spiders. Various natural conditions and the environment forced them to adapt, changing the structure and habits. And yet, the diverse appearance of the representatives of orb-weaving spiders does not prevent them from maintaining a series general characteristics allowing them to be assigned to the same family.
1 - (Nephila clavipes)
The length of the female of this spider reaches four centimeters, and the size of the male is smaller - only up to ten millimeters. The abdomen has a cylindrical shape. Coloration is orange with sparse yellow spots. Dark and light stripes alternate on the legs. In spite of large size, feeds on small prey. Distributed in Central and South America where it lives in forests, swamps and shady gardens.
2- (Argiope bruennichi) The females of this spider reach 25 millimeters in length (up to 40 millimeters with straightened legs), and the size of the males is up to seven millimeters. The color of the spider immediately catches the eye: the abdomen is painted with transverse black stripes on a white-yellow background, for which it is also called the wasp spider. Widely distributed in Europe, South Asia, China, Japan.

3 - an ordinary cross. Araneus diadematus)
The main habitats of the cross-spider are forests, bushes, roadsides and gardens. Females reach 18 millimeters in length, larger than males, whose size does not exceed nine millimeters. On the back of these spiders, a characteristic pattern in the form of a white cross is visible. Widely distributed in Europe North America and most of Asia, including Japan.

4 - Comet Spider. Gasteracantha sanguinolenta) This small spider has six spines on its abdomen and is colored yellow, red and black. Weaves a web at the tops of trees. Found in Central and South Africa.
5 - Asian golden spider. Nephila pilipes)
This spider can reach four centimeters in length. Weaves a golden web. It lives in the forests of Thailand, India and China. Often used for food.
6 - Precious spider. (Austracantha minax) Females of this Australian species reach a length of 12 millimeters, males - a little less. These spiders settle in colonies among the vegetation, hanging the web at a height of one meter above the ground. The abdomen of the spider is covered with thorns and painted in bright yellow and white colors on a black background.

LIFESTYLE
hanging by a thread
The survival of the family of orb-weaving spiders directly depends on the number of flying insects.

This is the only prey that can be caught in a web located at a relative height above the ground. For this reason, orb-weaving spiders prefer to settle in green areas, where the bulk of their potential victims are concentrated.
without haste
The life of spiders may seem too quiet and calm. All they do is wait until the next victim gets into their net. Zoologists call orb-weaving spiders sedentary, since their whole life passes on or near the web, at least after the spiders reach adulthood. The shape of their torso, unlike spiders of other families, such as jumping spiders and wolf spiders, does not allow them to move quickly, and on the ground they are rather helpless. And yet, in a number of cases, orb-weaving spiders leave their guard post and do other things. This happens during the mating season and during the construction of amazing silk cocoons in which the spider wraps its eggs. Many scientists suggest that spiders began to produce silk threads specifically to protect masonry.

mating games
The moment of reproduction, during which the male and female must come into contact, is one of the most dangerous and difficult in the life of spiders, especially males. Usually males are much smaller than females and can easily turn into their prey. To avoid this, male orb-weaving spiders approach the female's web with the utmost care. Having reached her, they pull the threads in a special way to make it clear to the female that we are talking not about the victim, but about a possible partner. When the female allows the male to climb the web, he cautiously approaches her and stands opposite her as shown in the photo above.

From this position, he introduces his pedipalps into the genital opening in the abdomen of the opposite female and deposits a spermatophore there, in which spermatozoa are enclosed. After a short copulation, the male leaves the web at a run to avoid unnecessary complications.

Food
The main prey of orb-weaving spiders is represented by flying insects that fall into the web in flight or jump.

Having found the victim, the spider entangles it with a web, completely immobilizing it, after which it pierces it with its powerful chelicerae and injects poison. After a short period of time, when the poison dissolves internal organs victims, turning them into mush, the spider returns to the prey and sucks out the nutrient mass. In the image on the right, a mantis was caught in the web of a wasp spider (Argiope bruennichi).

Reproduction
Spiders are egg-laying animals. This means that their babies develop outside the mother's body. Females lay their eggs in cocoons, or ootheca, made just before laying. In some species of orb-web spiders, ootheca take on amazing shapes and sizes. The thread from which the cocoon is made differs from the thread that goes to weaving nets. As the cocoon is erected, the female processes the threads with her saliva, strengthening them and giving them a papery structure. This helps to protect the eggs, which spend several weeks or even months in a cocoon under a variety of climatic conditions.

Ravenous hunters
All spiders are predators and, accordingly, excellent hunters, in large quantities destroying insect pests. They have extremely diverse ways of obtaining food: from stalking prey by wandering spiders to building a variety of intricate trapping devices by settled spiders. At the same time, orb-weaving spiders stand out from their counterparts in that they weave the most beautiful and largest webs.


The main hunting skill of orb-weaving spiders is the ability to weave a web. It should be borne in mind that a lot of insects get into the web during the day. With too much "harvest", the spiders have to constantly repair the web.

Although most orb-weaving spiders try to make it invisible, there are some, such as the wasp spider (Argiope bruennichi), which put a cross in the center of their web, or a stabiliment, which is formed by four zigzag web ribbons. At first glance, this does not make sense, since the zigzag unmasks the web. But scientists believe that this is done so that the web is more visible to birds. Seeing a web in flight, the bird will try to fly around it. However, spiders are not only hunters, but also victims. They are especially loved by birds that feed spiders to their chicks. Warblers are considered one of the main hunters of spiders and catch them both on the web and in their hiding places.

Artist's handwriting
Each group of spiders has its own web characteristic shape. The most interesting is the large concentric web of orb-weaving spiders, designed to trap flying insects. There are spiders that don't make any kind of web at all, like jumping spiders. Rough webs in the corners of walls and on tree trunks are characteristic of tangled weaver spiders and six-eyed spiders. Web spiders, which include black Widow, weave networks of irregular shape.

The main enemies of spiders
Birds: Many birds, such as warblers and tits, love to feed spiders to their chicks.
Wasps: Some wasps catch spiders in their webs. They paralyze the spider with a sting, drag it into their hole and lay an egg on the body of the spider. Upon hatching, the larva feeds on the spider as "live canned food".
Bats: Into the Dark the bats unmistakably find spiders and snatch them with precise movement
from the web.

Major casualties
Spiders: Female spiders are larger than males and can sometimes feed on their partners. In addition, there is a special family of spiders Mimetidae, which feed exclusively on spiders of other species.
Flies: They are the main victims of spiders and make up a significant part of their diet.
Grasshoppers: Grasshoppers' abundance and mode of locomotion make them a prime prey for orbweb spiders.
Butterflies: The uneven flight of a butterfly seeking flower nectar often ends up in the webs of a spider.
Dragonflies: The webs of some spiders, such as the wasp spider, are capable of holding even large insects such as dragonflies.

Hunting "skills" carnivorous plants and animals improved along with the development of life on our planet. Predators have always adapted to the behavior of their prey. The most cunning of them have managed to create traps that allow them to catch prey without chasing it, and without even entering into direct confrontation, fraught with injury and damage. Using traps, some species hunt prey that they cannot cope with in an open fight. A significant proportion of these sophisticated hunters are spiders, whose ability to weave silk webs has become proverbial. The web is one of the most durable natural materials. But not only spiders can build traps. There are other creatures that use deceit and cunning to earn their living.

Venus flytrap (Dionaea muscipula)
Flycatcher is one of the carnivorous plants. It grows on peatlands, poor in nutrients, and therefore needs protein food. On the upper surface two rounded leaf valves stick up three sensitive hairs that secrete a very sticky liquid. The flaps of the flycatcher instantly slam shut when an insect hits. The digested prey is absorbed by the cells of the plant.

Antlion (Palpares sp.)
Adult antlions are very similar to dragonflies (left) and catch their prey in flight. The larvae (top right) build amazing traps on the ground.

In the process of its development, a small larva digs a funnel in the sand (bottom right) and hides at its bottom. When an ant or something ground insect approach the edge of the trap, its walls collapse, and the animal cannot climb up. The larva grabs it with its powerful jaws, pulls it into the sand and eats it.

Wasp spider Argiope bruennichi) Wasp spider and spiders similar to it spin the most beautiful webs, reaching two meters in diameter. If such a trap is stretched between two bushes, it occupies almost all the free space and it is very difficult to bypass it.

Nemesia (Nemesia sp.)
Nemesia live on earth and dig underground galleries lined with cobwebs. They spend almost their entire lives in them. The entrance to the mink is closed by a lid, which the spider makes from the web. The lid is almost invisible against the background of the earth. The spider waits at the entrance to the gallery, holding on with its feet to the finest threads of the web scattered near the entrance. As soon as a small invertebrate steps on them, the spider jumps out of its hiding place, grabs the victim and drags it into the hole.

From myths to cinema
The ability of spiders to weave webs has fascinated people since ancient times. No wonder in the ancient and contemporary art characters with spider abilities act as skilled craftsmen or superheroes.
The myth of Arachne has become a favorite subject of classical art. The first depiction of this scene was found on an ancient Greek incense vessel dated to the 7th century BC. In painting, it is captured on the canvases of Rubens and Velasquez, and in literature it is found in Homer and in Ovid's Metamorphoses. Above is an illustration from Antoine Dufour's The Life famous women» (XVI century).


One of the myths Ancient Greece tells about a girl named Arachne, who once lived in Lydia and was a perfect master of weaving. Arachne was so skillful and proud that she was not afraid to challenge Athena herself, the goddess of the arts and the inventor of yarn and fabric, to the competition. Pallas Athena descended from Olympus to earth and accepted the challenge of a proud girl who dreamed of proving that she could weave better than a goddess. Each of the contestants created their own masterpiece. But Athena really did not like the plot depicting the gods, created by Arachne on an immaculately woven canvas. The goddess became angry, tore the fine work and hit the girl. Arachne could not bear the shame, twisted a rope for herself and hanged herself. Taking pity, Athena saved Arachne's life, but turned her into a spider. In Greek "Arachne" means "spider", so when you say modern name arachnids - Arachnida, we involuntarily mention the name of the Lydian girl.

Comic book hero who conquered the TV screen
The idea to give a person the ability to spin a web, just like spiders do, formed the basis of one of the most famous comics - Spider-Man.

According to the plot, the bite of the spider gave Peter Parker the opportunity to indulge in a superhero capable of throwing a web for long distances in order to move from building to building and catch villains who threaten defenseless citizens.
The comic book, which was released in the United States in the middle of the 20th century, served as the plot of several equally successful film adaptations. Unlike real spiders, Spider-Man did not have a spinneret. He released his web from his wrists.

Based on the materials of issue No. 4 Insects and their acquaintances

The family of araneomorphic spiders includes more than 3000 species, united in 170 genera. Diverse, unusual, bright - these are the main characteristics of this family.

One of the largest families, it is second only to jumping spiders. Despite their belonging to the same family, it should be noted that all orb-weaving spiders differ both in appearance and in their way of life. And only one characteristic remains unchanged: specific growths on the front pair of limbs, thanks to which spiders weave an unusual web.

The family of orbweavers includes one of the most common and large species- crosses.

The appearance of spiders

Representatives of this family have a relatively large abdomen and a soft external chitinous skeleton. Spiders are medium in size - 5-8 mm. As usual, the female orb weaver is usually larger than the male. Not surprisingly, males are sometimes afraid to approach females for fear of being eaten.

The color of the spider can be varied, with or without an intricate pattern, but most often there are light brown orb-weaving spiders with a specific pattern on the abdomen.

The body of a spider is composed of two parts: the prosoma and the opisthosoma. On the front, which is popularly known as the cephalothorax, there are six pairs of limbs. The two front pairs are chelicerae and pedipalps, and the last four are walking legs. There are 8 eyes in two rows.


The abdomen of an arthropod is soft and elastic. It has an oval shape, pointed at the end. The size of the abdomen is quite diverse, which is influenced by many factors. After eating or before laying eggs, the abdomen reaches an immense size compared to the usual state. The spiracle is located in the middle of the abdomen.

Where do Orb Weavers Live?


Orb-weaving spiders inhabit almost all corners of our planet. Their habitat depends on the presence of insects that these cute creatures eat. Ideal places for the residence of these spiders are shrubs, gardens and orchards. Plants attract a large number of insects, which spiders love to eat so much.

The web of orbs is a wonderful marvel!


Everyone who has heard at least once about the orbs, probably knows about them. amazing feature web weaving. Unlike many other families, Orbweavers do not strain themselves with a long and difficult process of searching for food. They pull the web and wait until the victim deigns to get into the network. Every day, orb-weaving spiders rebuild their webs, because the new web is more elastic, high-quality and catchy. The web of orbs is wheel-shaped, the threads are stretched radially. These threads are not sticky and serve as a base. Additional sticky threads are adapted to them. One strong thick thread that runs through the entire network is called a signal. In whatever place of the web the spider would not be, waiting for its prey, it holds this thread with two legs. Feeling the barely perceptible vibrations of this thread, he understands - dinner is served!

Man and Orb Weavers

It is not surprising that circle weavers - typical predators and good hunters. Thanks to this quality, they are assistants in the household. They are hunting in a variety of ways, relieving gardens and orchards from insect pests. It is worth mentioning that the webs of these arthropods play aesthetic role, causing delight with its grandeur and uncomplicated beauty.

Spider-cross - the most famous representative of the orbs


Among the family of orb-weavers there are those familiar to us - crosses. Family of orb weaving spiders one of the largest families in the world, it has more than two and a half thousand varieties of spiders. This family includes the most different types spiders, they are all different from each other both in body shape, in color, and in lifestyle. The only similar nuance is the presence of special outgrowths on the front pair of limbs in milestones of spider species belonging to this family, thanks to which they are able to weave special kind cobwebs. The most common and voluminous species of spiders of this family are Araneids, or as they are also called -.

Crosses live almost everywhere, but their largest number is observed on Far East, they can be found mainly in forest areas and in the fields. They weave just huge nets, which sometimes reach as much as two meters in diameter, they are very strong and solid, if some kind of insect gets into such a web, there can no longer be any hope of saving it. In the tropics, spiders are widely known orb weaving spiders, they even weave traps up to eight meters in size, and only females do this, they are very large, they cannot be confused with anyone because of their bright, very original color. Males belonging to this species of spiders are inconspicuous and almost invisible against the background of their females, primarily due to their "compact" size. The web that such spiders spin is striking in its strength, it is very difficult to break it, and besides, it is amazingly elastic, can be stretched to a length three times its original size.

Spider spider found almost everywhere, it got its name due to the pattern on the abdomen, similar to the shape of a cross, the color of such a spider is usually black, but the pattern is made in lighter colors. Although it is not easy to find spiders, their web is found everywhere, to the greatest extent in open spaces, namely in fields and gardens. They are of medium size, males are about one and a half centimeters, females - two and a half. Females lay their eggs where, in her opinion, no danger threatens them, mainly for these needs they choose tree trunks. Quite quickly, young offspring appear from the eggs, which develop simply at a phenomenal speed, and after only a few months it already turns into quite mature independent spiders.

No less interesting for dating and Venezuelan cross, his hallmark is that, unlike many other varieties of spiders, they live together. So, for example, females, laying eggs in cocoons, place them in a common nest, where they stay until the moment when spiders are born.

horned spider, or spiny orb-web spider(lat. Gastercantha cancriformis) belongs to the family Araneidae.

This little spider looks like a crab. Latin name species cancriformis translates as "crab", and the name of the genus is formed from two words gaster and acantha, which means "belly" and "thorn".

Spreading

This species is widely distributed in Costa Rica, Peru, Mexico, Ecuador, Honduras, Guatemala, Cuba, Jamaica and El Salvador. In the USA, it is often found in California and Florida, especially around the city of Miami Beach and along the coast. Atlantic Ocean. Separate populations inhabit many islands in the Caribbean Sea and the Gulf of Mexico.

AT last years the horned spider was also found in Colombia and Dominican Republic. To date, two subspecies of G.c. cancriformis G.c. gertschi.

Behavior

The spiny orbweb spider prefers to settle in mangrove forests and wet areas on trees and shrubs. Differs in enviable diligence. Every evening weaves a new network in the form of a circle, in adult females it can be up to 30 cm in diameter.

It is placed on the branches in an almost vertical position, most often at a height of about 6 m above the ground, and the animal itself, waiting for prey, is at the bottom of its hunting structure.

Smaller males live on threads placed near the female's nets. They do not hesitate to sometimes feed on her trophies, after rhythmically tapping their paws on the threads. Such courtesy allows them to stay alive and not be eaten by mistake. Up to three gentlemen can feed from their girlfriend's table at the same time.

The diet consists of all kinds of flying insects. Fruit flies, whiteflies, beetles and night butterflies become prey.

reproduction

Until now, there is no reliable information about the features of the reproductive behavior of horned spiders in wild nature. All data obtained only as a result of laboratory observations. It is unknown if the female mates in vivo with only one or a few males.

The mating season occurs in late spring or early summer.

The gentleman who decided to continue the family warns the lady about the seriousness of his intentions with four quick strikes along the edge of the net. He repeats them until the beauty demonstrates her attitude towards him. If she does not like the applicant, then she will simply drive him away.

In case of a positive answer, the male approaches his chosen one and, in order not to fall, joins her with a thread. Mating lasts about 35 minutes and is repeated several times with short breaks.

In autumn, the female lays eggs in the amount of 100 to 260 pieces in one oblong cocoon of a golden or less often greenish color. It attaches nearby lower part leaves.

The cocoon is attached first with thin whitish and yellowish threads, and then with thicker and stronger dark green ones. All this structure is additionally equipped with a special canopy.

After graduation construction works mother is dying. Its life expectancy does not exceed one year. Males live for about 3 months and die one week after mating.

Spiderlings hatch in winter and continue to be together for two to five weeks, and then scatter in different directions.

Description

The body length of females is 5-9 mm, and the width of their abdomen is 10-13 mm. The main background of the opisthosoma varies from white to orange, in some regions it can be black. Six spike-like processes extend from it, which are black or red. They are located along the edges of the opisthosoma in a diagonal order. Sometimes the tips of the spikes are colored orange.

The shape of the spines and coloration have many regional differences depending on the habitat. Top part opisthosoma is covered with miniature blackish dots like craters arranged in four rows.

The body length of males is 2-3 mm. It is more elongated than wide. The abdomen is gray, covered with white spots. The spines are weakly visible, they can hardly be distinguished no more than 4-5 pieces. The legs are short.

The bite of this horned spider is not dangerous for humans. It causes short-term pain, swelling, and redness of nearby tissues.

  • Class: Arachnida Lamarck, 1801 = Arachnids
  • Squad: Araneae = Spiders
  • Family Araneidae = Orb-web spiders

From the personal life of orb-weaving spiders

* Read more: Orb-weaving spiders; cross spiders; Curious Facts About Spiders

The evolution of spiders went primarily along the line of changes in behavior, and not in morphology. Therefore, there are so many works on the biology of reproduction, network building and other aspects of the life of spiders. And something new is being discovered all the time.

Arachnologists T. Bukowski and T. Christensen, studying the biology of the North American orb weaver Mecrathena gracilis, which belongs to the group of spiky orbs and has numerous spiky outgrowths on the abdomen, found out two features of their reproduction.

First, the male climbs into the net to the still immature female, shortly before her last molt. He molts fewer times than the female, and becomes sexually mature earlier. This is beneficial: a female that has not yet molted or has just molted is less aggressive. Perhaps, over time, she "gets used" to the presence of a male. Analyzing the condition of males sitting in the nets of females, American researchers found the absence of part of the legs and other injuries in only a small proportion of males. At first, the males behave passively and sit at the edge of the web, apparently fearing the attack of the females. After mating, the male quickly runs away, often even jumping out of the female's web. (Similar male behavior is known in many web spiders, including orb weavers.)

Secondly, mikraten are characterized by double mating: at first - short, and repeated - twice as long. In this case, the male tries to fertilize the female through both of her paired copulatory openings. Most likely, this is necessary in order to guarantee the appearance of exactly her own, and not someone else's, offspring - after all, the female is then able to mate with other males waiting in other corners of her network. Males try to remove competitors by cutting off their web threads, etc.; they themselves, by the way, can also mate with several females.

However, it remains unclear whether the sperm of the first male has an advantage in fertilizing the female, as has been noted in many other spider species. If it does, then the second pairing becomes unnecessary. Perhaps, for the first time, the male “out of excitement” introduces an insufficient amount of sperm? It is also not clear how the male monitors the age of the female. It is hypothesized that from time to time the male visits the growing female, and climbs into her net already "closer to the point" - before the last molt. But so far this hypothesis has not been proven.

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