The weevil beetle belongs to one of the many species of the Coleoptera family. Very often they are called elephants or mowers. Such a harmless name hides one of the most dangerous insects, destroying almost all known species of flora. The weevil family (lat. Curculionidae) belongs to the order Coleoptera, one of the largest among this species of beetles. Their number reaches seventy thousand. Elephants mainly live in tropical countries. About five thousand species of beetles have been recorded in Russia.
Pests of fields, gardens and vegetable gardens
The elephant beetle (another name is the mower) is a representative of the Coleoptera family. The harmless name hides one of the most dangerous insects, capable of destroying almost all existing plant species in the shortest possible time.
Weevils (from the Latin Curculionidae) belong to the order Coleoptera, one of the largest families of beetles. There are more than 70 thousand of them on the globe. The priority habitat for insects is countries with a hot tropical climate. More than 5 thousand species of weevils have been recorded in Russia.
Appearance
Representatives of the fauna are mostly small bugs, not exceeding 8-10 millimeters in length. Only certain species of tropical inhabitants can grow to truly gigantic sizes - up to 5-6 centimeters. The appearance of adults can vary significantly depending on habitat, feeding habits and potential threats. Species classification divides beetles into the following groups:
- by dimensions;
- by body shape (spherical, diamond-shaped, pear-shaped, rod-shaped);
- by the color of the chitinous cover (the color range is wide, some individuals have a specific coating on the skin of pollen or scales).
Anatomical features
The entire family of mowers, depending on the structure of the front part of the head, called the rostrum, can be divided into the following types:
- Long-proboscis. The rostrum is elongated, in most specimens it is curved and thinned towards the apex. The larvae live on plant branches or spreading leaves.
- Short-proboscis. The rostrum is small in size, it does not exceed twice the width of the base. In the ground the larvae feel protected.
In adults, the oral apparatus is located at the end of the proboscis. Elbowed antennae with a characteristic club grow from the apical recesses.
Female insects are larger than males and are physically more advanced. There are species without external sexual differences. An adult female, ready to reproduce, gnaws holes in the tissues of leaves or stems and lays eggs there. There can be 25-30 larvae in one clutch.
Life cycle
Male elephant beetles are distinguished by their ferocious disposition and stage entire battles for the right to fertilize a female, trying to hook each other with their horns and throw them on their backs. A fertilized female lays 12-20 eggs in the trunk of an old rotten tree to a depth of 25 cm. The embryonic stage of egg development lasts about a month, then the larvae appear. They are quite unpretentious in food and feed on any wood rot, quickly gaining weight. In a year and a half, they can gain weight up to 100 g and go through several developmental phases before pupating.
The formation of the pupa occurs within 2-3 months, after which it darkens, and then the process of hatching the beetle begins, which can last up to 2 days. Emerging adults have soft white elytra, which harden and darken within 4 days, and the elephant beetle takes on its final appearance. The lifespan of adults, as a rule, does not exceed 4 months.
Weevil larvae
Long-proboscis representatives of the species lay eggs in apples, nuts and other fruits. Short-proboscis relatives develop in the soil, where they feed on plant roots. The worm-like body is thickened and fleshy. The shape of the larva is curved, resembling the letter “C”. The outer shell is covered with sparse bristles. The head is covered with a dense, dark-colored chitinous shell. The deterioration of the condition of a young individual can be determined by a change in color - it can vary from white to brown. After some time, the weevil beetle larva turns into a pupa. The legs, the rudiments of a head with a proboscis and wings will be clearly visible on it.
Elephant beetle: description
Each type of weevil has a specific name that characterizes its habitat and “taste preferences,” respectively. These are the pear, drupe and apple flower beetles, the striped pea and raspberry-strawberry weevils, the hairy leaf weevil, and the nut fruit weevil (characterized by the longest proboscis, with which it mercilessly spoils nuts). All of them are united by a long proboscis and extreme gluttony.
What does an elephant eat?
The insect is not selective in food; it consumes leaves, stems, and eats the fruits and roots of the plant. Depending on what the elephant beetle eats, entomologists divide insects into the following groups:
- Monophages are pests that consume strictly one type of plant.
- Oligophages are beetles that feed on garden crops that are similar in appearance.
- Polyphages are omnivores that destroy any vegetation in their path.
These features mainly determine the habitats of weevils.
Some representatives of the species can be beneficial to humans. We are talking about mass destruction of weeds. Such insects are widespread in Brazil and Australia. Several types of useful mowers were brought to Russian territory, where to this day they continue to fight against salvinia, which pollutes water bodies.
Nutrition and lifestyle
Elephant beetles appear between September and December. They fly well and are able to travel long distances in search of food, although they prefer to move on the ground and tree trunks. The main activity is at dusk and at night, although sometimes beetles eating food can be seen during the day. But still, more often in the daytime they rest, hiding among the branches and leaves of trees.
Insects feed on the sap of leguminous and rutaceous trees, for which they gnaw the bark with their jaws and drink the secreted sap. They also enjoy eating ripe pineapples, bananas and other tropical fruits. In captivity, an animal can eat one avocado or other fruit of a similar size per day. Interestingly, in the event of a cold snap, beetles can maintain their own body temperature at the desired level, like warm-blooded animals.
Main varieties of elephants
It is impossible to describe all the larvae of weevil beetles and adult individuals living in the territory due to their countless numbers. Below is a brief description of the most common types.
Barn weevil. A small representative of the species with underdeveloped wings. It has spread around the world with grain crops, which it actively eats, thereby posing a danger to the contents of barns. Females make holes in grains of cereals or legumes and lay up to 300 eggs at a time. Damage to the crop is caused by both adults and larvae. Due to the extensive extent of the damage, grain after a weevil invasion is not suitable for food. The barn elephant beetle has several subspecies: rice, corn, and rice broad-proboscis.
Nodule striped weevil. The length of an adult pest reaches 5 millimeters. Affects legumes. The larvae destroy the root system, and mature insects eat the leaves and stems. During the season, the female of the species lays a record number of eggs - up to 3 thousand!
Beet mower. A large beetle with a short trunk. The body is lined with thick ash-gray scales. How dangerous are elephant beetles of this species? They destroy the sugar beet crop. The pest appears on agricultural land in early spring and feeds on weeds before beets germinate. Sexually mature individuals eat young shoots of the sweet crop. The larvae damage the root. As a result, the quality indicators of beets are sharply reduced.
The weevil is a fruit pest. It poses a particular danger to fruit trees, destroying all their parts, from the ovary and young shoots to flowers, bark and wood. The most widespread are vetch, Crimean, cherry, black and other types of garden pests.
Acorn elephant beetle. It is distinguished from its relatives by an elongated thin proboscis, the dimensions of which are equal to the dimensions of the body. The nose ends with strong jaws that turn into a drilling apparatus. Females lay eggs in oak acorns that have reached maturity. Drilling a hole in the fruit sufficient to create a clutch takes up to 8 hours for a female individual. The inside of an acorn is a favorable environment for the growth and development of larvae, which feed on its juicy pulp. Upon reaching maturity, the insects gnaw through the outer shell of the fruit and burrow deep into the soil. In the spring, pupation occurs.
Berry weevil. Destroys harvests of raspberries, strawberries, strawberries, blackberries, grapes and other sweet crops. The most common pest of this group in Russia is called the earthen elephant. It hibernates in winter and parasitizes plant bushes in the spring.
Buckwheat or Ussuri mower. Destroys crops and valuable crops. Adult representatives of the species cause damage to mature kernels, while the larvae eat stems and foliage.
To begin the fight against the weevil and protect the crop from destruction or damage, it is necessary to become more familiar with its development, feeding method and reproduction characteristics.
Reproduction of oak fruit worms
Acorns are necessary for fruit bearers because they contain a large amount of nutrients. To get to these substances, the fruit bearer has to drill into the hard shell of the acorn without interruption for about 6-8 hours. This is quite hard work, requiring great physical effort and tenacity from the female.
Acorns are used by beetles for reproduction.
First, the female makes a drilling point, and then describes first one or another semicircle around it. The surface of the acorn is quite slippery, and the long proboscis makes it impossible to rest against the wall of the acorn. The slightest wrong movement, the proboscis unbends, and the castle hangs in the air. In the early cold autumns there are many such females who die in an absurd way.
The fruit has an unusual proboscis.
If the work is completed successfully, the female turns and, using a red-colored ovipositor, lays her eggs deep in the acorn.
Over time, the eggs form legless larvae, a white-yellow body, shaped like a sickle. For the development of the larva in a secluded house there is everything necessary: food, warmth, safety.
Oak fruit larva.
After 3-4 weeks, the larva independently gnaws through the shell of the acorn. The larva enters the soil, and there it turns into a motionless pupa. And at the end of August, a young acorn elephant emerges from the pupa.
With the first warmth, insects begin to fly, and the life cycle repeats again. The major part in the development of the oak beetle is occupied by a two-year generation, during which the larvae overwinter in the first year, and adult beetles overwinter in the second year.
Basic methods of dealing with elephants
Agronomists and gardeners starting to grow crops must take a set of measures to destroy and prevent the appearance of weevils. It is also necessary to get rid of pests at the household level.
Large agricultural companies practice the following methods of combating elephant beetles:
- Deep plowing and loosening of the soil in the spring-autumn period is a real opportunity to destroy eggs laid in the ground or larvae preparing for wintering.
- Infected plants are removed and burned.
- Practice rational crop rotation.
- Application of modern insecticides.
The measures described above to combat weevils in combination will ensure a significant reduction in the number of insects in the fields and in storage facilities.
Prevention measures
Of course, prevention will not provide a complete guarantee that beetles will not appear on the site. But the number of weevils can be significantly reduced if you follow simple rules.
- follow agricultural practices and care rules;
Weevil beetle.
- choose your neighbors correctly;
- carry out pruning and digging, plowing in the fields;
- remove carrion and litter;
- feed and monitor the health of the plant in a timely manner;
- carry out preventive spring spraying.
Mower in residential premises
The weevil in an apartment or private house is a common phenomenon. In a human home it is always warm, cozy, and there is something to eat. This is the most favorable environment for reproduction. In order not to say goodbye to stocks of grain and cereals, owners of apartments and houses must respond in a timely manner to the appearance of unwanted guests and systematically carry out preventive measures in order to prevent their return.
First of all, all cereal stocks must be sorted out, the flour sifted, and any pests found must be collected and destroyed. An effective way to disinfect damaged cereals is by frying or freezing. The described method also has its drawbacks: after prolonged exposure to extreme temperatures, the room will have to be thoroughly cleaned.
Traditional methods of fighting weevils
Insects with a long trunk do not tolerate ash, mustard, ammonia and laundry soap. Solutions with one of the above components, evenly sprayed over the surface of the plantings, if not completely get rid of the invasion, will significantly reduce the number of pests.
No less effective are infusions of tansy, wormwood and capsicum.
When folk remedies fail, homeowners resort to using chemicals. To prevent fruit poisoning, processing must be carried out in strict accordance with the instructions. The following drugs are popular today: karbofos, Inta Vir, Actellik, Antonem-E, Nemabakt, etc.
Rational application of the pest control methods described above will allow you to get rid of it for a long time and protect the crop.
