Views: 8724
10.05.2017
Since ancient times, the invasion of voracious locusts has been considered a terrifying natural disaster. Some flocks, when flying from place to place, form huge clouds of insects in the sky, the area of which can reach thousands of square kilometers and number several billion individuals. The pest devours all the vegetation along its route, so after its invasion only bare soil remains.
The locust is omnivorous and feeds most actively in the early morning and late evening, eating leaves, flowers, young shoots and fruits of plants. During the course of a day, an adult can cover a distance of fifty (!) kilometers, which makes it very dangerous in a crowd large number relatives.
A massive revival of locusts and the formation of a large swarm of pests occurs approximately once every ten to fifteen years. During this period, a huge flock can cover a distance of three hundred to a thousand kilometers per day (if there is a fair wind) and simultaneously occupy an area of about two thousand hectares of land.
The attack of huge swarms of locusts was first mentioned in the chronicles of Rus' dated 1108. As a result of this invasion, terrible famine occurred everywhere. They say that trouble does not come alone, and massive insect attacks were repeated in 1094, 1095, 1103 and 1195.
In 1824, locusts raged in the Kherson, Ekaterinoslav and Tauride provinces.
As part of the fight against this harmful scourge, Alexander Sergeevich Pushkin, among other officials, was sent to the south of Ukraine. Returning from a business trip on May 28, the poet submitted a report to the office with the following content:
Locust
Collegiate Secretary Alexander Pushkin.
Locusts are extremely voracious. Every day, an adult insect eats as much plant food as it weighs, so it is not for nothing that the locust attack became the eighth Egyptian plague and a sign for Pharaoh so that he would finally allow Moses to lead the people of Israel out of Egypt ( Ref. ).
Even now, the locusts, no, no, will manifest themselves. This happens especially often on the African continent, which is facilitated by the hot climate.
The last significant locust outbreaks occurred in the North Caucasus (in 2010 and 2015), and the largest outbreak was recorded in 1875 in the United States, when a huge swarm of insects caused colossal devastation in the state of Texas.
In Ukraine, no evidence of mass reproduction of locusts has yet been recorded, but if average temperature air will continue to rise (and such a trend is visible), then the factor global warming may cause outbreaks of a sharp increase in the locust population in our area.
Locusts are found everywhere, except that they are difficult to detect in the northern regions of the globe, since they are a heat-loving insect and in natural conditions, with the onset of cold weather, the number of insects sharply decreases.
When flying, locusts make a creaking sound, so when a huge colony of insects flies, the sounds of individual individuals merge, amplifying many times, and become an eerie rumble, which from a distance resembles the roar of summer thunder.
Adult (imago)
Total locust family ( lat. Acrididae) has about ten thousand species of insects, but the most harmful are two forms: Asian and migratory ( lat. Locusta migratoria).
The appearance of the locust is unsightly and resembles a large grasshopper or cricket, only with more powerful jaws.
The body of an adult migratory individual can reach six centimeters in length, and the largest can be over fifteen (up to twenty) centimeters.
The wings of an adult insect are greenish with brown spots, the rear ones are transparent and have a green or yellow tint.
The appearance of the winged form of the flying locust is preceded by an ordinary green filly - a single one, which can easily be found on an ordinary sun-drenched lawn with wildflowers.
One adult locust lives from eight months to two years and has two life stages, forms or phases of development. These forms are very different from each other in appearance and physiology and in the nature of behavior, therefore they for a long time attributed to various types locust family.
Currently, scientists perceive both forms as the same species.
Single phase of insect development
The single locust is larger in size and has a rich light green body color, which is why it received the nickname “Green Filly”. This phase of locusts is mostly harmless, since the insect leads an inactive lifestyle and has only one life goal: to maintain the population of insects of its species. Therefore, as long as there is enough food and everything in the locust’s life is going well, the filly lays eggs, giving birth to green fillies similar to themselves. But as soon as food becomes insufficient (usually this happens in dry years), the locust begins to actively lay eggs, the DNA of which contains a “march” program for searching for food and the density of larvae begins to increase in arithmetic progression. Soon they begin the transition to the second (gregarious) phase of development.
· The gregarious phase of insect development
The gregarious phase of locusts is extremely dangerous. At this stage, the insect acquires a more saturated color, and the body undergoes metamorphosis. The imago becomes more adapted to long flight, and thus the filly turns into a locust.
Adult insects of the gregarious phase begin to cluster into dense flocks as they reproduce.
Scientists entomologists conducted an interesting experiment, during which several mirrors were placed in front of a sedentary female green filly. Soon, constantly bumping into her reflections and conflicting with them, the female began to lay eggs with a nomadic life programmed into them. As it later turned out, the green filly turns into a locust of the gregarious phase due to a banal lack of protein, which causes the female to sharply increase the population of flying individuals.
In years with abundant food and moderate weather conditions Without significant temperature fluctuations, single individuals do not cause much harm to plants, so you should only be wary of the gregarious phase of the birth and development of insects.
Reproduction
With the onset of the first cold weather (usually in October), the locusts die, but before that they lay eggs for wintering, creating egg capsules or capsules (clutches) in which they place from fifty to one hundred eggs. The capsule is produced from the female gonads and has the appearance of a foamy liquid, which, having hardened, becomes a reliable shield for the eggs, thanks to which they do not freeze.
During the summer, one female gives birth to one to three generations of insects.
In the spring, as the earth warms up, larvae emerge from the eggs. white, which soon darken and begin to feed on vegetation. Over the course of about a month, sometimes a little more, the insect larva goes through five developmental stages (instars) until it turns into an adult insect.
The mass reproduction of locusts in the gregarious phase is directly related to weather conditions. Trying to maintain water and protein balance in the body, the flock must continuously feed, so it constantly moves in search of fresh food.
A lack of protein turns some of the insects of the colony into predators and, thus, dividing the flock into two groups. One part, running away from its brethren, seeks food, constantly searching for new vegetation, and the other part at this time replenishes protein reserves, eating, including its relatives.
Pest control
Agrotechnical measures
Preventive measures against locusts (in those areas where there is a high probability of a massive invasion of harmful insects) must be carried out thoroughly and deep processing(ploughing) the soil, which destroys the egg capsules.
Chemical methods of control
Effectively protecting plantings in the face of unprecedented gluttony and mass numbers of locusts is possible only with the use of chemical methods plant protection.
If there is a mass concentration of locust larvae in one area, use pesticides with a validity period of at least thirty days. To treat and kill insects, they take such preparations as “Karate”, “Confidor”, “Image”, but it is possible efficient use poisons to combat the Colorado potato beetle.
A good result is shown by the systemic drug “Clotiamet VDG”, which provides reliable protection against locusts for three weeks. This poison is good because it can be effectively used in a tank mixture with other microfertilizers, protective agents and plant growth stimulants, but it is necessary to first test for compatibility with other chemicals.
Preparations such as “Gladiator” and “Damilin” effectively destroy locusts (both larvae and adult insects). The insecticide "Damilin" has negative impact on larvae, slowing down their development and disrupting the timing of the formation of the chitinous body shell, as a result of which the insects die.
The big advantage of the drug is its low toxicity.
Locust is dangerous insect, capable of destroying plants in their habitat. Outwardly, it resembles the famous grasshopper. Crickets are similar to her because they belong to the order Orthoptera. Its body size is larger and its flood flows are different.
The locust insect is the most dangerous pest field, meadow, garden plants. Gathering in flocks numbering millions of individuals, they suddenly appear in a new place and leave behind a bare area. It is difficult to resist, its benefits are minimal, so you need to know how to fight.
Many people saw the locust, studied its description, and looked at photographs. She lives almost everywhere. These jumping green insects are easy to spot along the road, in a forest clearing, in a vegetable garden, in the north. They sit peacefully on the leaves, chirp, do not bring any benefit, but do not harm the farm either.
The filly lives alone, posing no danger. As soon as locusts unite in swarms, they turn from a harmless individual into a formidable pest, whose gluttony is immeasurable. Their droppings, which remain after an invasion of leaf beetles, are also considered toxic.
Appearance
The body length of locusts is 3 - 7 cm. Females are slightly larger in size than males. Body coloration varies. Easily adapt to habitat conditions. They camouflage themselves with the surrounding vegetation, so they can be green, yellowish, brown, or olive. The longer the life expectancy, the darker the color of the locust. Quickly changes color when it joins a flock.
The large head is connected to the body almost motionlessly. It seems that this is a single indivisible organ. Large eyes stand out on the head, long elastic antennae stand out. Each insect has two pairs of wings. The front ones are dense, have noticeable brownish-brown or black spots, the rear ones are transparent, with a green or yellowish tint visible on them.
The flying insect has powerful jaws. It gnaws and crushes thick stems and powerful leaves.
While in the larval stage, it crawls along the stems. Growing up, it begins to jump, then flies. Thanks to its strong hind legs, it makes jumps. There are species of locusts that cannot fly when they become adults.
Habitat
Different types of locusts have adapted to life in certain regions. It appeared in Russia a long time ago, sometimes destroying entire fields. Most common in the southern regions.
It is found in Africa, has reached Europe, and lives in the Sahara Desert and the steppes of Kazakhstan. She is not afraid of the cold of Siberia or the humid climate of New Zealand. Habitats are often warm steppes. Doesn't like the Arctic at all.
Nutrition
Locusts hide in flowers, among tall grass, under leaves. Here an abundance of plant food is found for locusts. They consume almost any part of the plant. They do not disdain small leaves, stems, and young shoots. Flying insects daily eat green vegetation, the mass of which is approximately twice the body weight.
During its life, one locust eats up to 350–500 g of food. In some places, there are individuals that feed on poisonous plants, becoming potentially dangerous food for birds. In color, they differ from other species in the brightness of their color, warning of the presence of poison. They look very attractive, as the photograph proves.
Uniting in hordes, they become dangerous. A swarm of locusts flies about 50 km per day in search of food. Small insects, slightly larger than a grasshopper, develop a voracious appetite. They destroy vegetables and fruits, gnaw reeds, and destroy grain fields. After their invasion, everything disappears. Only stones, concrete, and asphalt will survive.
Living in a flock, they can eat weak individuals. This type of eating is driven by a lack of protein in food. With a lack of nutrition, the number of pests decreases. Entire species disappear when diseases spread within a group.
Many people are interested in where green locusts come from in huge numbers? The female is capable of laying hundreds of eggs, which will produce many larvae. Its reproduction and residence are unusual, as are the stages of locust development, which is worth noting in the description.
Locusts live in two stages:
- gregarious;
- single.
When living alone, the green filly is inactive. It's practically harmless. In autumn it lays eggs in a special hole in the soil. During the winter they remain in the ground, and in the spring young white individuals appear.
The filly larva needs food, so they begin to feed heavily. With rapid development, changes occur: they turn into imagoes, change color.
Anticipating a dry year, poor in food, changes occur in the female’s reproduction. Locust eggs are initially programmed to search for food in hiking conditions. Adult adults form flocks, while larvae form numerous swarms.
Mating precedes the reproductive stage. The male attracts females to his society by secreting a special hormone. As soon as the female approaches, he jumps on her back and clings tightly. A spermatophore is released into the base of the clutch. This is how the locusts begin breeding.
An insect goes through mandatory stages of development. The female lays eggs
pre-preparing the egg capsules. There are up to 100 eggs in one capsule. In winter they do not freeze out because the insect envelops them with a special foamy liquid for preservation. In the spring, a larva emerges from each egg laid. Its development continues intensively. After a month, an imago-like individual without wings is formed. Over the course of a month and a half, the emerging larvae transform 5 times until they turn into adult locusts. During the summer months, three generations of young animals can be produced.
Types of locusts
It is difficult to list all the varieties of locusts. There are quite a lot of species. Since the insect reproduces quickly, it periodically occupies new territories where there is enough food. Each type has its own characteristics.
An unusually voracious Moroccan locust, feeding from morning to evening. She has a distinctive cross on her back, her legs are red on the bottom and yellow on the top. Eggs are laid by females in egg pods, which they dig in unplowed fields.
There are up to 36 eggs in one cocoon. When migrating, they unite in huge flocks. From a distance, such a horde moves like a black cloud. The length of the flock can be up to 200 km. They instantly eat up an entire field or garden. They gnaw the stem at the base, destroying plantations of reed, tobacco, cereals, and cotton. Moroccan locusts quickly develop mutations, making them impossible to control. She is not afraid of insecticides.
Asian
The Asian locust has an unsightly, boring color. The color of the cover is from brown to greenish-yellow. Length up to 6 cm. Lives in Korea, Mongolia, Afghanistan, China, and is sometimes found in the Caucasus and Europe. Can fly, lives mainly in herds. Females lay about 1,500 eggs. In the month of March, larvae emerge from eggs.
Young fillies are black or yellow in color; those living in a flock are orange with black dots. Harmful agriculture, eating grain crops. They destroy fields of rye, soybeans, corn, barley, potatoes, alfalfa, rice, and melon. They eat bushes.
Desert
The desert locust lives in Africa, Pakistan, and India. There is little food in this place, so they eat everything that comes in their way. They are believed to be an unusually voracious species of locust. They often fly across the ocean to find food. Migrations are typical during the breeding season. The color is yellowish lemon.
Individuals living alone have a body color similar to the color of grass and sand. Black and brown spots are visible on the lids of desert locusts. Reproduction times vary. They can produce up to four offspring per year. They are not afraid of poisons.
Italian
The representative of the Italian locust is the Prussian. According to the description, it resembles a gray grasshopper with wings colored slightly pinkish. They prefer to live in Italy, but it is unknown where they come from in Central Asia, the Caucasus, and Altai.
Eats potatoes, sunflowers, melons. Loves to destroy fields with cereals and legumes. small insect(up to 4 cm in length) eats green mass twice its own weight.
Egyptian
There are rare insects. These include the large Egyptian locust, which lives in the Sahara. Its body reaches a length of 8 cm. Local residents talk a lot about the benefits of the insect, who add dried insects to bread cakes.
There are many recipes where this insect is marinated, fried, or cooked in sauce.
Knowing what a locust looks like, it is unlikely that anyone will confuse this harmful insect with a harmless grasshopper.
During the time of the prophet Moses, although in fact this insect struck terror into people before. Mention of locusts is found in Sumerian writings dating back 8,000 years ago. The plague of locusts and the famine that it entails was a real disaster for humanity, comparable to wars, pestilence and floods.
Flying monster
Swarms of locusts are the largest in nature. A record number of these insects was observed in the west in 1874.
Locust clouds covered 500,000 km 2, an area equal to two states of Colorado.
According to preliminary estimates, the number of locusts in this swarm was 12.5 trillion, weighing 25 million tons. If a swarm of locusts catches a fair wind, it can cover a distance of 500 kilometers in just 24 hours.
In one day, one locust can eat as much as its own weight. In 1988, a small swarm of locusts from Africa flew across the Atlantic and overran the Caribbean.
However, nature is not able to constantly satisfy such exorbitant appetites, so the new generation of locusts has to be content with a more modest diet. But there comes a time when the locusts again unite in a swarm, preparing for new invasions.
Favorable conditions
The locust belongs to the family of true locusts ( Acrididae) from the suborder Orthoptera. When there is an abundance of food, it leads a solitary lifestyle, but when certain conditions(usually due to a lack of food in hot, dry years) begins to reproduce so intensively that too much of it accumulates in one place. Some generations die from lack of food, while others flock together.
Due to the conflict with the “neighbors,” the hormonal balance of the locust changes. The nymphs acquire not a green, protective color, but a black and yellow color and go in search of new sources of food. Gradually the flock grows - more and more individuals join it. Individual members of the flock obey the movements of their closest neighbors. When the number of insects becomes high enough, the flock turns into a well-coordinated squad, moving in a single stream. Thus begins the invasion.
During the “march,” the nymphs molt and turn into winged, sexually mature individuals. Usually the flock moves during the daytime. As darkness falls, insects land and begin to consume food. There are only a few types of terrain that are immune to locust infestations. So, she does not fly in the rain and stays away from the jungle - she does not like the leaves of tropical trees. Locusts are capable of rising to a height of about 2000 m, but not higher - it is too cold there, so the swarm cannot overcome mountain ranges.
Migratory locusts do not always form swarms. Usually she leads the lifestyle of a harmless “grasshopper”.
There are billions of locusts in one swarm. They usually appear after dark, and by morning there is nothing left of the crops.
One locust eats only 2g of food per day, but a swarm of a billion insects consumes 200 tons!
a brief description of
Name: migratory or Asian locust
Latin name: Locusta migratoria.
Size: up to 5.5 cm.
Method of movement: jumps and flies.
Geography: Asia, Africa, sometimes Europe.
Food: green plants.
Lifestyle: crowded, gregarious.
Life expectancy of locusts: 5 months.
The locust insect lives everywhere, except Far North and Antarctica. You can meet him in a forest clearing, in a city park, in a ditch by the side of the road, in a vegetable garden. In its own way, this is a unique creature in which two development programs are genetically embedded. While the locust lives as a hermit, unaware of its own kind, it is completely harmless. But as soon as she sees her closest relatives, the spirit of collectivism awakens in her. Insects unite in numerous swarms and cause devastating damage to farmers.
General characteristics of the pest
Locust sizes vary from 3 to 7 cm. Females are larger than males. The body is oblong, attached to it are rigid elytra and a pair of translucent wings, which remain invisible when folded. The color is very variable and depends on the age, conditions and lifestyle that the locust leads:
- Even individuals emerging from the same oviposition may differ in coloring.
- What a locust looks like is also determined by the phase of its development.
- In the European zone, single individuals are predominantly yellow, brick, green, olive, brown in color, which helps to camouflage against the background of the surrounding vegetation.
- The older the individual, the darker its color becomes.
- If the locust joins the swarm, it acquires the same color as the rest of the team members.
The locust belongs to the order Orthoptera of the locust family.
The large head is not particularly mobile. Large crescent-shaped eyes and a rectangular, almost square muzzle of the locust give the insect a good-natured appearance. The gnawing mouthparts are represented by powerful jaws that help gnaw through even the thickest and most durable stems. The insect gnaws leaves with its upper mandibles, and only then crushes them using its lower mandibles.
A distinctive feature of locusts from their closest relatives: crickets and grasshoppers is their short whiskers, their length does not exceed half the body.
The pinkish hind legs are well developed, which allows the locust to jump at a distance of 20 times its length. It is no coincidence that insects are endowed with jumping abilities. In the larval stage, they still cannot fly and their motor capabilities are limited to crawling and jumping. Some species do not exhibit flight activity even as adults.
How long locusts live depends on conditions environment. Rainy seasons provoke the development of fungal plant diseases, which leads to insect infection and death. Natural enemies: wild wasps, beetles, birds can also shorten life expectancy. Humans also make their contribution by destroying pests. If the locusts are in optimal conditions and did not become anyone’s victim, then it can live from 8 months to 2 years, depending on the species.
Insect diet
For the most part, locusts spend their time on leaves, flowers, and grass. Locusts are the most vegetarians without any obvious food preferences. Most species do not care what kind of crop it is - wild or agricultural. They feed on the leaves of plants, trees, shrubs, and all ground parts of plantings. Only some species have a preference herbaceous plants. During its life, an insect eats an average of 300-350 g of plant mass, and the daily volume is twice its own weight.
For certain species they serve as food poisonous plants. As toxic components accumulate in the locust's body, it becomes poisonous. These individuals are characterized by bright, flashy colors, which seem to warn of the danger of everyone who wants to feast on locusts.
When insects gather in swarms, what the locusts feed on depends on the objects that come across its path. In this case, even thatched roofs, reeds, not to mention vegetables, grains, melons. As eyewitnesses say, during insect attacks, locusts only devour bricks and iron.
The insect is bred as food for various exotic animals. Therefore, the question of what locusts eat at home does not surprise anyone. In insectariums they are fed twice a day with grain, green herbs, and some owners even prepare sprouted wheat for their pets.
How do locusts reproduce?
Females begin laying eggs in late summer, in autumn. To do this, she makes a hole in the soil and lays her eggs in it. A special secretion is released from a special gland, which, like foam, fills all the holes between the eggs and creates a strong, reliable protection. Once hardened, the ovipositor appears in the shape of a long tube called an egg capsule.
One female makes several clutches, after which she dies. In European latitudes, the eggs spend the winter in the ground, and with the arrival of warmer weather, white larvae emerge from them. They are distinguished from their parents by their tiny size and underdeveloped wings. After a few hours, the larva acquires a characteristic color and begins to feed intensively. After 4-6 weeks, having undergone 4 molts, it turns into an adult.
In warm tropical climates, females lay eggs year-round and the number of generations per year can be 6-8.
Phases of development
As has already been noted, locusts have two development options: solitary and gregarious, which are strikingly different from each other.
Single cycle
The locust filly, as single individuals are called, develops freely with an abundance of food and leads an inactive, shy lifestyle, which is why it was previously systematized as separate species. Single individuals are characterized by camouflage coloration and pronounced sexual dimorphism. The filly does not cause significant harm.
In fact, a single phase of locust development is necessary for the preservation of the population. The female lays eggs and when the food supply becomes insufficient to feed all the larvae, the locust moves on to another stage of development.
Herd development
Association in swarms is observed in hot, dry years, when locusts begin to experience a shortage of food and moisture. According to recent studies, a lack of protein provokes females to intensively lay so-called “campaign” offspring.
Interesting! In laboratory conditions, many mirrors were placed in the area of a sedentary filly. Seeing her reflections, the female began to actively lay eggs according to the “walking program”.
Gathering into a large tribe, intense friction against each other, the visibility of their own kind, the smell of fellow tribesmen causes a powerful production of serotonin in the nervous system.
Due to the release of the hormone, individuals literally undergo dramatic morphological changes in a matter of hours:
- change of color;
- increase in size;
- leveling of sexual dimorphism.
Clusters of adult flying locusts are called swarms; the larvae form swarms. The population moves, as if on command, in one direction. Weakened individuals are eaten along the way by their fellow tribesmen. Adult locusts are capable of long flights and cover from 90 to 140 km per day.
The length of the flocks is measured in tens of kilometers, and the number can reach several billion individuals. The weight of such “collectives” reaches tens of tons.
The locust invasion cannot go unnoticed. The sound of approaching insects is comparable to the sound of thunder, and the flock itself covers the sun.
On its way, the flock devours literally everything, even the thatched roofs of houses, vineyards, orchards, vegetable and grain plantations. Just decades ago, locust attacks caused famine. Now the flocks are causing colossal losses to farmers. In 2015, a locust invasion in Russia destroyed an area comparable to the territory of an entire state, for example, Romania.
Types of locusts
There are many types of locusts. Most of them quickly adapt to new conditions and develop new territories.
The largest locust
This is the largest locust of all migratory species. The size of females reaches 8 cm, males are slightly smaller - 6 cm. Color can vary from dirty yellow to brown. There are many veins on the wings. Lives mainly in the Sahara and Hindustan.
The most saturated bright yellow in larvae and males. The mating process of bright individuals is very interesting. The male begins to chirp furiously, attracting the female. Female who liked it musical accompaniment, kindly allows the male to climb on her back. Mating continues for several hours. Some cavaliers like to mount the female so much that they continue to do this even at the moment when the female is busy laying eggs. Life expectancy is only 8 weeks.
Asian locust
The Asian migratory locust has inconspicuous colors in brownish, greenish, and yellowish tones. The wings are also not characterized by bright colors. The insect can be found throughout Europe, Asia, the south of the Caucasus, Siberia, Korea, and China.
Egyptian locust
This is the largest locust found in Europe. The body length of females can reach 7-8 cm. Only the South American locust can compete with its size. According to some sources, they grow up to 20 cm in length, but there is no exact evidence of this.
The Egyptian locust is distinguished by its gray, olive, greenish, and yellow color. Shins are bright orange color. Terrorizes Europe, North Africa.
The benefits and harms of locusts
The greatest damage is caused by swarms of locusts that destroy fields and plantings. However, the average person, who does not care about the safety of the crop, is more interested in the answer to the question of whether locusts bite. The insect eats exclusively plant food and does not bite humans, unlike its fellow grasshopper.
An equally pressing question is whether locusts are eaten. Orthoptera are the most commonly consumed insects after ants. IN African countries it is fried and mixed into flat cakes. Arab women several centuries ago they could prepare 2 dozen dishes from locusts. Cooking recipes have lost their relevance due to a shortage of ingredients.
In California, during locust outbreaks, entire feasts were held. The captured insects were soaked in a marinade, then crushed and prepared into soups. The Japanese marinate in soy sauce and fried. In a word, there are many recipes for cooking locusts, but not everyone can appreciate its taste, not so much because of inaccessibility, but because of disgust.
Locusts and grasshoppers: how to distinguish
Locusts and grasshoppers have several differences:
- The locust's body is long, while the grasshopper's is shorter and wider at the sides;
- The grasshopper's whiskers are longer;
- the grasshopper is active at night, and the locust during the day;
- locusts eat plants, and grasshoppers eat insects;
- The grasshopper's muzzle is oblong, the locust's is rectangular.
Steppe (Asian) migratory locust Locusta migratoria. (Acrididae, Caelifera)
Distribution area: Asia, Southern Europe, North Africa. Habitat: mostly soil, sometimes shrubs.
Dimensions: females - 6 cm, males - 4 cm Food sources (adults): grasses, cereals Food sources (larvae): grasses, cereals Duration of development: in the egg - 15 days, larvae - 30 days.
Lifespan: 8 weeks The migratory steppe locust has long been a scourge for people living in tropical and subtropical regions. When mass reproduction suddenly begins, these insects become pests. Millions of these insects attack the fields of peasants and devour everything growing on them. At present, the reasons for the irregularly recurring mass reproduction of the steppe migratory locust are still not clear. To study this dangerous phenomenon, scientists different countries A long-term scientific project is being carried out.
At normal reproduction rates, migratory steppe locusts are peaceful, sedentary insects that do not cause harm. Only during mass reproduction does hunger force these insects to wander: larvae move on the ground, and adults fly through the air. This behavior of larvae can be observed in captivity if they are deprived of food sources.
The color of insects varies from light gray to light brown with dark gray and brown spots. Light gray veins stand out on the wings. Females and males can fly. Upon reaching sexual maturity, the color of the body and legs of males becomes yellow. The color of the larvae is brown and black.
Biology. In its distribution area, the steppe migratory locust Locusta migratoria lives in dry steppes and agricultural lands created on them, feeding mainly on grasses and cereals. It is most active in bright sunlight and high temperatures.
During mating, males make chirping sounds to attract females. Mating lasts several hours, the males are on the backs of the females. At this time, copulation occurs. In some cases, males remain sitting on females while laying eggs.
To lay eggs, the female makes holes 8-12 cm deep in the soil. In this case, the abdomen, like a telescope, extends to this length. The channel in the soil is filled with foamy secretion, into which the female lays an average of 40-50 eggs. After hardening, the foam forms a cocoon, which provides protection for the eggs - both from enemies and from drying out.
The larvae emerging from the eggs free themselves from the cocoon and crawl to the surface. Larvae size
6 mm, they are white in color, with a soft body. After the cuticle hardens, the growth phase begins. The transformation is complete, that is, the larvae look like adult locusts.
Desert migratory locust Schistocerca gregaria (Acrididae, Caelifera)
Distribution area: North Africa, border regions of the Sahara. Habitat: grasses and shrubs.
Dimensions: females - 8 cm, males - 6 cm
Food sources (adults): grasses, blackberries (Rubus spec), leaves of shrubs and trees. Food sources (larvae): grasses, blackberries (Rubus spec), leaves of shrubs and trees
Duration of development: in the egg - 18 days, larvae - 35 days. Life expectancy: 8 weeks.
The color of insects is dirty yellow. The wings are dark brown with veins. Females and males can fly. At the onset of puberty, the color of the body and legs of males becomes bright yellow. The color of the larvae is bright yellow, green and black.
Biology. The desert migratory locust Schistocerca gregaria in its distribution area lives in the border regions of deserts and semi-deserts, feeding on grasses, cereals and foliage. It is most active in bright sunlight and high temperatures.
During mating, males make chirping sounds to attract females. Mating lasts several hours, the males are on the backs of the females. In some cases, males remain sitting on females while laying eggs.
To lay eggs, the female makes holes 8-12 cm deep in the soil. In this case, the abdomen, like a telescope, extends to this length. The channel in the soil is filled with foamy secretion, into which the female lays an average of 40-50 eggs. After hardening, the foam forms a cocoon, which provides protection for the eggs - both from enemies and from drying out.
The larvae emerging from the eggs free themselves from the cocoon and crawl to the surface. The size of the larvae is about 6 mm, the color is white, the body is soft. After the cuticle hardens, the growth phase begins. The transformation is complete.
"Foam Locust" Autarches milharis (Pyrgomorphidae, Acridoidea, Caelifera)
Distribution area: Indo-Malay archipelago. Habitat: bushes. Dimensions: females - 7 cm, males - 5 cm.
Food sources (adults): blackberries (Rubus spec), swallowtails (Asclepiadaceae). Food sources (larvae): blackberries (Rubus spec.) swallowtails (Asclepiadaceae)
Duration of development: in the egg - 4 months, larvae - 3 months. Life expectancy: 4 months.
The color is bright, variegated (black, white, orange green, red). This splendor of flowers serves as a warning to enemies that Pyrgomorphidae are unpalatable, smell bad, and produce a substance that has a repulsive odor (Skaife, Lebger, Bannister, 1981). In addition, these insects protect themselves with a foamy liquid secreted from an opening at the base of the hind legs. The coloration of the elytra is olive with yellow spots. The pronotum behind the head is orange, on the upper side of the body it is black, and on the sides it is white. The head is painted in black and white colors, below - bluish-green. The chest is red, the abdomen is black and red with a ring-shaped pattern. Females have 4 hard horny outgrowths on their abdomen. Males are smaller than females. They have a soft, blunt growth on their abdomen.
Insects of this species lack the chirping organ (Schrillorgan). The hearing organs are well developed, located behind the thoracic region of the body in the middle of the first visible abdominal ring. They can be distinguished by the naked eye; they appear as round depressions on the body of the insect (Skaife, Lebger, Bannister, 1981).
Biology. Insects of this species and two the following types They lead a diurnal lifestyle and live on the branches of bushes, along which they slowly move. Mating also occurs on a plant that serves as a food source for the insects.
Females descend to the ground to lay eggs. The female presses the end of the abdomen to the surface of the soil and, turning slightly, screws it into the ground. The female begins to lay eggs when the abdomen is immersed in the ground in such a way that the head, chest and legs are pressed to the surface. The eggs are oblong in shape, covered with a foamy secretion that binds pieces of earth and forms a kind of capsule.
The larvae emerging from eggs are covered with a shell that protects them when moving through upper layer soil. Immediately after emerging to the surface, the larvae shed this shell and quickly climb onto the plant that serves as their source of food.