Insects managed to develop to such a scale thanks to their small size (from 0.2 to 0.4 mm), although the size of some individuals reaches 5 mm. Ticks inhabit the upper layers of soil. Their main difference from spiders is their body, divided into two parts or a whole body. At the ends of their legs, ticks have claws and suckers, with the help of which the parasites are held on their host.
- Dangerous types of ticks
- Popular types of ticks in the regions of our country
- Bed mites
The anterior appendages of parasites (chelicerae) are a piercing-cutting mouth structure.
The second pair of appendages (pedipalps) is free in primitive representatives of the species, but in others they are part of the head, which is movably attached to the body. The pedipalps allow the parasite to attach to the victim. The number of eyes can be from 0 to 5. The body can be soft or protected by shields and shells.
Not all types of ticks are dangerous to humans. The diet of many of them consists of decomposing organisms, so they are one of the links in the complex process of humus formation.
Dangerous ticks!
Some types of ticks cause dangerous diseases in humans and pets.
What types of ticks exist?
There are more than 40 thousand species of ticks in the world, but they can all be divided into three orders:
- parasitiforms - mites that parasitize the body of humans, animals or birds and feed on the blood of their prey,
- acariform - they do not drink blood, live under the skin of a person or in his home and feed on dead skin particles,
- Haymaking mites - these creatures have no relationship at all with humans or animals; they parasitize exclusively on plants.
Each order includes many different species of mites.
By 2011, the number of described tick species was 54,617, of which only 900 species prefer to feed on blood, and 144 are extinct.
Why is it not easy to remove a tick?
The proboscis of insects has an elongated shape. It is equipped with numerous small sharp teeth directed backwards . This design allows the parasite to “anchor” in the host’s tissues and not fall out for a long time. The moving parts of the proboscis are capable of cutting through the skin of feeding animals . After this, the insect invades the host’s body. It feeds by sucking blood, lymph or dissolved tissue.
It is important to note that due to the significant increase in the body of ticks, they must be pulled out very carefully . Firstly, to avoid squeezing the infected insect contents into the wound. Secondly, so as not to tear the insect’s body. Otherwise, the proboscis will remain in the skin, and you will have to take it out additionally. We talked about how to remove ticks in the article: Tick bites: how to protect yourself?
Life cycle of a tick
The most common type of tick that can bite a person or his pet is the ixodid tick . It is with his bites that most people go to the hospital. This tick has a flat body and 4 legs on each side. The head of the tick is a continuation of the body, and is not separate, as, for example, in the cockchafer. A tick that has drunk blood swells and begins to resemble a bean.
Mainly female ticks drink blood; males need it in much smaller quantities. Each saturation with blood brings the female closer to the readiness to reproduce.
The life cycle of a tick includes four stages:
- Egg.
- Larva.
- Nymph.
- Adult.
Let's look at the life cycle of a tick in more detail:
- The breeding season for ticks is summer. It is at this time of year that sexually mature females seek males for fertilization. Under normal climatic conditions, 50–65% of the total females are fertilized.
- The next step is that the fertilized female looks for a temporary host in order to get enough blood.
- After this, the female is ready to lay eggs. This process takes from two weeks to three months. For the oviposition site, female ticks choose litter from fallen leaves. The depth at which they lay eggs is 3–5 cm. The maximum clutch size is up to 20 thousand eggs.
- When the oviposition process is completed, the female lives for a few more days and then dies. This happens because irreversible changes in the digestive system, as well as the collapse of internal organs, occur in her body.
- New ticks may hatch this year or next when the weather conditions are right. When the time comes, the eggs hatch into larvae. They, unlike adults, have three pairs of limbs. During this period, ticks do not attack anyone, but hide in a shelter. They develop their protective cover. Tick larvae at this stage begin to look for food. To do this, they attack small animals, making their way into their burrows, or birds.
- Having sucked blood, the tick larva falls away from its victim and begins to prepare for molting. After molting, she enters the nymph stage. Nymphs gain body weight, grow more developed limbs, and their reproductive system begins to develop. During this period of ticks' life, small animals or small livestock become their victims.
- The feeding process takes an average of a day, after which the tick begins its final molt, as a result of which another adult tick appears in the world, ready to reproduce further.
Egg
Under a microscope, mite eggs resemble fish eggs. This is a large cell, covered with a soft membrane and containing the yolk, cytoplasm and nucleus. The outer shell can be smooth or ribbed. The eggs have different colors and two shells: the outer one is dense, and the inner yolk is thin. The shape of the egg can be:
- round;
- flattened;
- elongated;
- oval.
Each type of tick has its own specific egg shape.
The size of the egg relative to the body length of the mature female is very large. Typically the egg is larger than the last abdominal segment. After the eggs mature, the female lays them in a secluded, damp place.
Reproduction of ticks
Because of this, some species of ticks have developed a very original method of viviparity: postmortem. With this method, after the eggs ripen by autumn, the female does not lay eggs, but dies. The eggs remain overwintering in the female's body. In the spring, the larvae hatch and eat their way out into the wild. One of the reasons why ticks die is procreation. The uniqueness of this method of reproduction, according to experts, arose from the fact that the eggs are too large to be laid without the death of the female.
Interesting!
In two species: bread mites and pot-bellied mites, true viviparity is observed.
Where does a tick live and what does it eat?
The favorite habitat of ticks is damp, shady places. These include forests and parks. However, ticks can be found in the country house, lawn, and some types of ticks even prefer caves or cracks in buildings.
Ticks do not live at heights, but prefer grass and bushes. From here they crawl onto a person or animal and begin to rise, so they can bite a person, for example, behind the ear. Having found a suitable place, the tick begins to screw its nose into the human skin until its head goes deep into the skin. The respiratory organs of a tick are located in the area of its legs.
Ticks feed on blood, but they are not always able to find a suitable donor. Then the ticks begin a “fasting day”, which can last up to 8 years. During such periods, the tick's metabolic process slows down very much.
Ticks are most active in the summer, because it is at this time of year that they reproduce, but the first cases of tick bites are recorded already in mid-spring.
From personal experience I can say that the most evil ticks in Siberia are in April-May. As soon as warm days arrive, hundreds of arachnids go hunting. At this time of year, after every walk with the dog in the nearby forest park, you have to remove 2-4 ticks from yourself and your four-legged friend.
Table: the importance of ticks in nature
| Harm | Benefit |
| They bite livestock on farms. | Predatory mites destroy spider mites. |
| They carry diseases. | An enzyme in tick saliva that prevents blood clotting is of interest to scientific medicine. |
| Some types of mites cause damage to crops and garden plants. | Some types of mites are used to produce mimolet cheese. |
Ticks are far from the top of the food chain; they are eaten by sparrows, starlings, guinea fowl, as well as lizards and toads.
Sexually mature individual
Ticks
The structure of a tick is usually considered using the example of ixodid ticks as the most common in the world. This group is the most dangerous.
External structure
The tick usually has an oblong body, where the thorax and abdomen are fused together. Hungry individuals are flat above and below. Well-fed females resemble a leathery pouch. The tick's "skin" is actually a chitinous cuticle. On the back of arthropods, a compacted cuticle forms a protective shield. In females this shield is located only on the front part of the body; in males it covers the entire dorsal part. Under the cuticle are the internal organs and muscles of bloodsuckers.
Interesting!
Some species of ixodids also have scutes on the underside of the body.
In the photo of the tick under a microscope you can see the lateral appendages of the arachnid. In many species, the length of the appendages is so different that it is often impossible to understand how many legs a tick has. But all species of these animals have only 4 pairs of legs. What may appear to be the front legs are actually the chelicerae and pedipalps of the tick, which are part of the structure of the mouth apparatus.
On a note!
Chelicerae and palps in ticks also belong to the limbs. These limbs may once have been another pair of legs, but today they are included in the mechanism of the oral apparatus.
Head
The head is so small that the proboscis seems attached directly to the body. The piercing-sucking mouthparts of the tick have changed significantly compared to the gnawing apparatus. The tick's proboscis has a hexagonal or rectangular base. The structure of the proboscis is quite complex:
- chelicerae;
- pedipalps;
- hypostome.
The latter in ixodids is equipped with teeth that help to stay on the victim. Chelicerae in some species of arthropods have turned into a kind of scissors. The sucking ones have fused into a hollow stylophoran tube. Stylophore – protection for stylets formed by modified cheliceral fingers. In bloodsuckers, these “fingers” are transformed into a tube through which blood enters the digestive tract.
On a note!
The pedipalps (palps) have only an auxiliary value and are often reduced.
Legs
The adult has 4 pairs, the larva has three. The legs of the mite are homologous to the limbs of insects:
- pelvis;
- swivel;
- hip;
- knee;
- shin;
- paw.
Since the tick clings to the victim first with its front pair of legs, the legs of predatory and parasitic species are equipped with hooks and suction cups that help to stay on the animal.
Appearance of a tick
In most species of ticks, the pelvic part is motionless and fused with the body. Only primitive species retained mobility of the pelvis. Given the microscopic size of the objects of study, it is possible to examine the segments on the legs only through a microscope under high magnification. A close-up illustration of the arachnid’s legs shows that the segments are very similar and it is very difficult to distinguish them from each other.
Throughout its life, a tick's limbs may change. The main anatomical change occurs in the hind limbs. In predatory species they are curved and look like pincers, with the help of which the arthropod is held on the victim. Leading a “calm” parasitic lifestyle of scabies, the legs are thickened, shortened and have powerful suckers. Tetranych mites have glands on their legs that secrete a sticky liquid that helps them move along smooth surfaces.
Internal systems
The diagram shows an dissected female ixodid tick that has drunk blood, indicating the purpose of the internal organs depicted.
The internal life support systems include digestive and respiratory. The circulatory system of ticks is not developed. The analogue of the heart muscle is located on the back and has an oval shape. The aorta comes off from it. The vascular system is not developed, and the blood - a white liquid in the tick - pours into the body cavity.
The digestive system is represented by:
- mouth opening;
- two salivary glands;
- pharynx;
- esophagus;
- intestines;
- anus.
The excretory organs of mites include not only the latter, but also several more. The intestines have a more complex structure:
- midgut with several lateral blind branches;
- small intestine;
- hindgut.
Adjacent to the hindgut is the rectal bladder, which is one of the excretory organs.
The excretory organs, in addition to the rectal bladder, include the salivary glands located in the mouth. Salivary glands are needed by parasites to store an anesthetic secretion, which is used for injection when piercing the skin with the proboscis.
Important!
Thanks to the secretion of the salivary glands, the bite of an arthropod is invisible to the victim.
The rectal bladder is a repository for waste products, as it receives digestion products and dead cells of the midgut. Pathogens found in the intestines also come here. For this reason, tick feces can also be hazardous to health.
Respiratory system
Tick bite
When a tick bites into the skin, it breathes not through the anus, but through the respiratory openings - stigmata on the hind legs. When inhaled, air enters the trachea - thin tubes running along the entire body of the arthropod. The stigmata of ticks are protected by special organs called peritremes. In ixodids, peritremes are plates that are adjacent to the stigmas from the sides and behind. Other groups have tubes of varying degrees of length and shape.
The respiratory system of this subclass of arthropods is very poorly studied. The question of what a tick breathes actually remains open. If we talk about the respiratory organs, then these are the trachea. If we consider the composition of gases, the needs of arthropods have not yet been studied. There is a group of granary mites that can live at a CO₂ concentration of 30%.
Mites in food, dust and on plants
Now let's talk about ticks, which do not feed on blood, but can also cause damage.
Flour mite
This pest feeds on flour and cereals and can spoil a lot of food. The size of the insect is only 0.3–0.7 mm. You can tell that there are flour mites in your products by the mint-like smell and sweetish taste of the product.
Dust mite
This arachnid lives in human homes and feeds on dust and dead skin particles. It is because of this that allergy sufferers and asthmatics suffer. The size of these pests is only 0.5–0.1 mm. You can determine that a dust mite is in your home only by a sudden exacerbation of asthma or the appearance of an allergy.
Spider mite
This small creature parasitizes plants. Spider mites are a nuisance to gardeners and flower lovers and can destroy plants. There are several types of these parasites. Here are the most common of them:
- red spider mite - this pest prefers flowers and is found on roses, callas, orchids,
- cyclamen mite - the favorite victim of this arachnid is, of course, cyclamens,
- wide spider mite - loves cacti, citruses and oleander,
- bulb mite - affects the bulbs of tulips, hyacinths and other flowers underground, gnawing out its core, which leads to the death of the plant,
- Atlantic and Pacific ticks - live in warm regions, feeding on the leaves of citrus fruits and palm trees,
- flat orange mite (flat mite) - mainly violets suffer from it.
Video: which mites harm plants
Why do spiders have webs?
The web that spiders weave is intended not only for building trapping networks, but also for:
- building cocoons for eggs. In this case, the web is used as a construction tool for the other side of life - its continuation. Actually, the construction of trapping nets by spiders is also a way to prolong life, because an individual dies when there is no food. But here we mean maintaining the integrity of the population. This function of the web has a much more global purpose;
- escape in case of danger. Here we are talking not so much about maintaining the integrity of the population as about preserving life. Thanks to the web, the spider can escape from something that poses a potential or obvious threat to it.
As you can see, the web is not only a means of attracting prey, but also a protective mechanism. An example is the use of a spider's web as a tool to build a cocoon. In this case, the spider web performs a protective function for the offspring of the arthropod. As you can see, a web is needed not just to get food.
Which ticks harm humans and animals?
There are several types of ticks that harm humans and animals. Some of them attack humans or animals outside the home, and some live in human habitation. What unites them is that they all love blood. The danger of these ticks is that they carry diseases that can threaten human health and even life. Such diseases include encephalitis, borreliosis, ehrlichiosis and many others. The most common types of such ticks are:
- ixodid tick - bites both humans and their pets and is a famous carrier of diseases, has a flat body measuring 0.5–0.7 cm and a dark red color with a black head,
- argas tick - lives in caves, burrows, crevices of houses, its size ranges from 3 mm to 3 cm, the bites of this tick are very painful,
- gamas mite - parasitizes rodents, birds and is especially common in rural areas, but can also settle in city apartments, especially on the first and last floors, its size is from 0.2 to 4 mm,
- subcutaneous mite - causes the disease demodicosis, a person develops a red itchy rash in the area of the face and scalp,
- scabies mite - lives under human skin and gnaws through a whole system of passages there, causing acariasis (scabies), the infected person develops red rashes on the skin in the groin area, between the fingers, armpits,
- ear mites are a nightmare for cats and dogs, they grow in the ears and cause severe itching, unfortunate animals rip their mite-infested ears into blood,
- bed mite - lives in a person’s bed, feeds on the skin and causes itching, unlike a dust mite, bites a person, although it does not drink blood, like, for example, the ixodid tick.
Video: which ticks harm humans and animals
Symptoms of demodex activation
Subcutaneous mites, if active, cause a special disease - demodicosis. Its symptoms resemble ordinary acne, but there are specific signs indicating the presence of a parasite.
Constant shine and excessive production of sebum (oil) in combination with pimples, red spots and small ulcers indicate a parasitic nature of skin problems. The appearance of bumps on the skin of the face, scales and crusts on the eyelash line are also common manifestations of subcutaneous mites. Itching and the sensation of movement under the skin usually intensify at night. With a long process and lack of treatment, the foci of the disease take on a terrifying appearance, become inflamed and infected.
How to protect yourself from ticks
Despite all the dangers that a tick bite brings, you should not give up walking in the fresh air. In order to protect yourself and your pets from tick bites, it is enough to follow simple rules of protection:
- wear closed clothing with long sleeves and elastic cuffs, such as a tracksuit,
- prefer clothes made of light-colored fabric, this makes it easier to spot ticks,
- use special sprays that are marked as suitable for protection against ticks,
- use special tick collars for dogs and cats,
- When you come home, carefully examine yourself and your pets for ticks.
In humans, ticks are most likely to be found in the groin, behind the ears, armpits and on the stomach. In animals - in the neck, abdomen, and also in places where the fur is thickest.
This year my dog was bitten by several ticks, and they all burrowed into the neck area, where her furry “collar” is. Walking with my child in the spring, I was worried that my daughter wouldn’t be bitten by a tick. Of course, we have an insurance policy for such a case, but we don’t want to take any unnecessary risks. When getting ready for a walk, I put the girl on a turtleneck with a high collar and long sleeves and tucked it into tights, and on top - regular pants and a windbreaker with sleeves with elastic bands. On the head - a hat. Thus, the only exposed areas of the body were the face and hands.
Protecting your home from mites, including dust mites and bed mites, is very simple. This does not require any special effort; it is enough to simply keep the house clean, avoid the formation of dust accumulations, and periodically wash or dry clean mattresses and bedding.
Video: how to protect yourself from ticks
Features of parasite hunting
It is worth noting some behavioral features of insects. It is noteworthy that only those individuals that have reached a certain degree of aggressiveness attack . This is, in particular, determined by the ambient humidity and temperature conditions. Also, the activity of the tick is affected by its internal water balance . If an insect has been sitting in ambush for a long time and has used up the necessary supply of fluid in the body, then it interrupts its hunt. To restore strength, it moves into the lower layers of vegetation, into the litter, where it is again saturated with life-giving moisture. After this, the insect continues its attack.
basically two hunting modes characteristic of ticks. The first is lying in wait tactics. The insect climbs onto the upper parts of the plants and takes a wait-and-see position. The second option is active pursuit. Yes Yes. They are capable of sniffing out and chasing their prey . Therefore, careless lying on the grass under the shade of a tree should be treated with caution. Insects sense their prey at a distance of 5-10 meters and can actively move in its direction. That is why the largest accumulation of parasites is observed where domestic animals are grazed or where there is a recreation area.
How to tell your child about the dangers of ticks
The main thing you should focus on when talking about ticks with children is the age of your interlocutor. You can explain to a child aged 2–4 years that during a walk you should not run on the grass and under bushes, as pests live there and can bite very painfully. Older children can and even need to be explained why ticks are dangerous, besides the painful bite. At 5–8 years old, a child can already understand that these insects can infect their victims with terrible diseases. The consequences of diseases should be described in a gentle form, which will be a good motivation not to look for adventures in the grass. It is quite natural that a child will have questions. For example, is it possible to crush a tick found on clothing or in the grass? It is important to explain that this should not be done under any circumstances, because in this way you can become infected with diseases, since the blood of the insect will get on your hands.
Ticks are not so scary if you know why they are dangerous, what they look like and how to protect yourself from them. In addition, by studying the literature about ticks, you can learn a lot of interesting and useful things about them.
Causes of subcutaneous mites
With healthy immunity, the presence of subcutaneous mites is invisible and does not cause problems. With weakened immunity, the parasite penetrates into the deeper layers of the dermis. Most often, the insect lives on the face of the female half of the population. Those with delicate, light-colored skin, as well as middle-aged and elderly women, are most at risk of infection.
Where do subcutaneous mites come from? Any contact with an infected carrier of the parasite causes the appearance of a mite. Using the same towel, dishes, cosmetics, clothing and accessories, as well as hugging and kissing are the most common ways to become infected and become a carrier of a dangerous parasite. Other causes of subcutaneous mites represent a number of internal factors. Reasons for the activation of subcutaneous mites:
- Disturbances of the endocrine system;
- Constant severe stress and anxiety;
- Diseases and disorders of the digestive system;
- The presence of some additives in the cosmetics used;
- Frequent consumption of alcohol, spices, coffee abuse;
- Periodic exposure to the sun or solarium.
It should be noted that domestic animals can very rarely be carriers, since the insect is not typical for them.
