There are a lot of pests that interfere with a person’s normal life. They attack him in a house or apartment, destroy or spoil food in the bins, in the beds. This extensive list also includes weevils or elephants. You can effectively deal with a pest only by knowing the characteristics of its behavior and habitat. There are more than 5 thousand species of weevils, but not all of them are harmful to humans.

Division by type

The main difference is in the location of the oral apparatus and its appearance. Short rostrum (Adelognatha) in short-proboscis pests, long - in long-proboscis (Phanerognatha) elephants. The length and type of the proboscis determine the type of larva in the weevil.

• In insects with a short proboscis, larval worms grow and reach sexual maturity in the soil, feeding on plant debris, small filamentous roots of plants.
• Most of the long-proboscis is characterized by the development of larvae in the tissue mass of plants, which serves as a source of nutrition and protection from external adverse factors. Much less often, worms crawl out, damaging flowers or leaves.

Weevil larvae without legs. The body is thickened, fleshy. Depending on the type, they different color: red, cream, white, tan.

Weevils also differ from each other in such characteristics:

• the size;
• food ration;
• body shape and color.

Unlike larvae, adult beetles lead a hidden night image life. They are active in search of food at night, hiding in the soil at dawn. Some varieties of weevils develop in fruits on trees, in young shoots. Under the tender bark, they gnaw through passages to a fairly large depth.

Attention! Despite the diversity of species, all pests are united by an indefatigable appetite and the appearance of the mouth apparatus - the proboscis.

"Beach" for legumes

The erroneous opinion that beans and other legumes do not "like" the pest is refuted by the nodule weevil and its bristly "brother" - the pea elephant. The insect can be found on all plantations with growing legumes, except for the northern territories. It endures winter on lands under decaying remains of leguminous plants or in the soil layer. Shows activity in early spring. It feeds on young greens of cotyledon leaves, vetch buds, clover, peas, etc. In a dry season, with a lack of moisture, weevils are especially dangerous, because. deplete plant shoots. The larvae go deep into the ground and destroy the internal filling of nodules on the roots of leguminous plants, leaving only a shell from them.

stone fruit pest

Cherries most often, cherry plums, plums, apricots, less often, are affected by the cherry weevil, harming their generative organs. It is also called a cherry pipe. After overwintering in the soil litter, the beetles rush to the swollen buds. Mass attacks on cherries and other stone fruits are carried out during the flowering period. First, the juicy tissue of the kidney is eaten, then the young green leaves. The ovary is gnawed from the inside. Kidneys crumble. The laying of eggs by the female occurs in the pericarp. The hatched larva develops by feeding on the nucleolus of the bone. Fruits lag behind in development. For the period of cherry ripening, the ripened larva from the damaged fruit goes into the ground, preparing for wintering. Deep digging under the crown of a tree, the use of chemicals at an early stage immediately after flowering, the mechanical destruction of damaged buds are the main methods of dealing with cherry trumpeter.

From whom to save rice

The rice weevil is a typical pest of grain and products made from it. He does not refuse dry fruits, tobacco, bakery products. It is found everywhere in the southern regions of Russia. Particularly susceptible to low temperatures. It tolerates the lack of moisture in feed well (adult beetles can eat food with 8% moisture content). Under favorable conditions (southern regions) produces up to 8 generations per year, while in temperate climate no more than two generations develop. Differs in high fecundity - up to 580 eggs.

"Garden suffering" or beet weevil

Headache for farmers. Spoils the tender shoots of garden plantings, as well as their roots. Withstands winter. Leaves an area infected with eggs and larvae for several years. Covers Europe, Central Asia. Feels great in Siberia. It is easily recognizable by its long rostrum, light gray shiny scales with numerous dark spots. Oblique markings crossing the back obliquely are noticeable. Having laid a clutch of eggs (from 20 to 200 pieces), the female dies. After a week, the larvae that appear quickly gain weight by eating the roots of plants. "Dislike" to the beet pest is associated with damage to various varieties of beets, eaten by them to the ground.

Strawberry diseases from weevil

Strawberry weevil causes irreparable damage to beds by eating flower buds. As a result, about 90% of the strawberry crop can be destroyed. Raspberries also suffer - losses reach half of all berries. Gets blackberries, rosebuds. Therefore, these crops should be planted as far apart as possible. Activating with the first fine days (air temperature +10°С, soil +13°С), beetles first eat leaves, then feed on dust particles of unripe buds. At the same time, strawberry varieties with female flowers and underdeveloped stamens suffer less, because. they have a smaller supply of food for the larvae. After mating, the female gnaws a hole in the buds, laying an egg in each, gnawing the pedicel. Damaged and brownish underdeveloped inflorescence falls off. If we take into account that about 50 eggs are laid in total and the same number of buds die off, then it is clear how the yield drops.

A disaster for the bins

The barn weevil harms grain, products of its processing, both in the stage of development of the beetle and the larva. Adult individuals feed on grain, flour products. Eggs are laid in grain. And the larva itself develops, eating away the nutrient medium inside it. Breeding in large quantities, barn pests eat large volumes of the product. Especially in granaries, bakeries, food bases, confectionery shops, etc.

Who are the oaks afraid of

This type of pest, like acorn weevil, develops exclusively in fruits. It is easily identified by a long thin proboscis of the same length as a diamond-like body 5-8 mm in size. A particularly strong jaw drilling apparatus perforates the thick acorn shell. From the eggs laid in the fruit, the larvae develop, feeding on the cotyledons and the juicy embryo. Damaged acorns are easily recognizable by their characteristic brown spots, wrinkled shell and underdevelopment. Fallen oak fruits should be collected immediately after the fall, until the larvae come out of them. Healthy acorns are stored in cool rooms. The oak weevil has natural enemies: titmouse, nuthatch, pika.

Attention! The main harm from weevils is that in any phase of development they eat and damage plants. Therefore, they are considered the most dangerous and common pests.

Knowing the features of development, habitat of weevils, it is possible to predict their activity, as well as plan measures to combat the pest.

Morphology

Imago. Weevil, 4 - 8 mm long, with elytra sharply tapering towards the top. Rostrum thin, long, curved. Antennae covered with sparse hairs. Body and elytra with long yellowish-brown, reddish-brown or grayish-yellow scales.

Slightly noticeable spots are usually present on the elytra. On the back, in the area of ​​the seam, there is no comb of hairs.

Scutellum nearly square, wide.

All hips are equipped with teeth.

sexual dimorphism. Different-sex individuals differ in the structure of the genitals. Secondary sexual characteristics:

Female. The rostrum is longer than that of the male.

Egg oblong shape. Covers are white. Dimensions 0.75 - 0.8 x 0.32 - 0.38 mm.

Larva fleshy, crescent-shaped with a brown head. Length 6 - 8 mm. The covers are yellowish-white.

chrysalis, like all beetles, develops in the cradle. It is free, soft, white with easily distinguishable parts of the future beetle.

Development

Imago. With a two-year generation, which is usual for middle lane European part, summer begins at the end of April - May and lasts until September. Until mid-July, beetles undergo additional feeding, damaging young leaves, shoots and flowers of various deciduous tree species. By the time acorns are formed, they accumulate on fruit-bearing oaks, where they damage the acorn cotyledons.

mating period. Egg laying is observed simultaneously with the release of the acorn from the cupule and their achievement of half of the normal size. Laying lasts until September. Females lay one or several eggs under the acorn shell or in a plush. In low-yielding years, up to 20 eggs can be laid in one acorn. Usually from 3 to 8. The fertility of one female is 120 - 150 pieces.

Egg. The development of the embryo lasts from 10 to 15 days.

Larva develops in the stomach for 23-30 days, feeding on the cotyledons, gnawing their passages and filling them with excrement. At the end of this period, she gnaws a hole in the shell and goes into the soil. Acorns damaged by weevils fall off. Some of the larvae remain in the acorns and end up in storage. In the soil, the larva constructs a cradle, which is a kind of soil extension with smooth walls. With annual generation, some of the larvae pupate in the same summer. Most larvae hibernate inside the cradle and pupate only the following summer. Some larvae can, being in a state of diapause, winter twice.

chrysalis develops within a month.

Imago. With a yearly generation, young beetles hibernate in cradles and emerge from the ground the next spring. With a two-year generation, young beetles hatched in the summer do not linger in the soil, but immediately come to the surface.

Development features. In some areas of the range, beetles emerge twice: in spring (overwintered adults) and in summer in the first half of August. Kind of light-loving. First of all, acorns of edge and single trees are damaged. Prefers clean, sparse stands.

Morphologically related species

By morphology ( appearance) the imago is close to the described pest. Curcuionucum). Main differences: elytra on the posterior clivus have a protruding comb of hairs, antennae with dense hairs.

In addition to this species, the Cherry fruit beetle is often found ( Curcuiocerasorum), also similar in morphology to the adult acorn weevil ( Curcuio glandium).

Geographic distribution

acorn weevil distributed in the European part of Russia, in the Caucasus in Siberia, and in Western Europe throughout the oak growing area.

Maliciousness

acorn weevil damages oak acorns and hazelnuts. Harm the larvae. Damaged acorns are easily identified by brown spots at the injection sites. They crumble earlier than healthy ones, as a rule, wrinkled, underdeveloped, inside with dark excrement.

With the development of more than one larva in the stomach, the ability to germinate is lost. Under favorable development conditions, the pest destroys more than 50 - 80% of the acorn crop.

Acorn weevil - (oak, oak fruit) - Curculio (= Balaninus) glandium Marsh.

Systematic position: Coleoptera order, weevils family Curculionidae.

Damages

– acorns various kinds oak. The nature of the damage - the larvae first gnaw a soft pad at the base of the acorn, then grind into the cotyledons, which severely damage or sometimes destroy. Damaged acorns are clearly visible by brown spots at the injection sites. They crumble earlier, are usually wrinkled, many are underdeveloped, inside of them there is a dark compressed, and subsequently structureless feces.

Maliciousness

In some years, the weevil destroys up to 90% of the acorn crop. The strongest abscission of infected acorns is observed in August.

Spreading

Everywhere in oak forests.

Favorite stations

The greatest infestation of acorns is observed in sparse plantations, on separate trees.

Generation

Most often, two-year, one-year and three-year generation is rare. With a two-year generation, the weevil does not have a pronounced periodicity of appearance.

Diagnostic signs

by phases of development.

Bug

and 5-8 mm long, rhombic in shape. Body color dark brown to black. The elytra are covered with grayish-yellow hairs. The semicircular head is elongated into a conspicuous thin, slightly curved rostrum, which in the female is longer than the length of her body. The rostrum of the male is much shorter. The forelegs are notched. Scutellum almost square, body wide. The elytra are short triangular, narrowed from the shoulders.

Eggs

white oval. The larvae are whitish-yellow with a brown head, crescent-shaped, fleshy, 9-10 mm long. Thoracic segments with 5 rows of dark setae.

chrysalis

free, yellowish-white, somewhat curved, 9-11 mm long and 4.5-5.0 mm wide. It has a noticeable long rostrum. There are only 4 setae on the dorsal side of the abdominal segments.

Phenology

The flight of beetles begins at the end of April - in May and lasts until September. Until mid-July, beetles undergo additional feeding and damage delicate leaves, shoots and flowers of various tree species (oak, birch, linden, etc.), and then accumulate on fruit-bearing oak trees, where they damage the cotyledons of acorns, plunging the rostrum into them. In the second half of July, when the acorns emerge from the plush, which has reached half its normal size, egg laying begins, which lasts until September. The female lays one or several eggs under the acorn shell, sometimes in the plush. In low-yielding years, up to 20 eggs can be laid in one acorn, more often 3-8. The egg stage lasts 10-15 days. The development of the larva in the stomach lasts 23-30 days, after which it gnaws a hole in the shell and goes into the soil, where it remains up to next year and pupates in July-August. At the end of August, young beetles appear, which remain in the soil until spring. Often some of the larvae enter diapause and remain to overwinter a second time.

Duration of outbreak

Representatives of this group are not characterized by outbreaks of mass reproduction. The number of pests of fruits and seeds depends primarily on the characteristics of the fruiting of fodder species and is characterized by much less sharp fluctuations than in openly living insects. Reconnaissance supervision should be carried out in August-September when examining fallen acorns. Damaged acorns are clearly visible by brown spots at the injection sites. They crumble earlier, are usually wrinkled, many are underdeveloped, inside of them there is a dark compressed, and subsequently structureless feces.

Control measures

Treatment of trees with insecticides in late June - early July, during the period of additional feeding of beetles. In seed farms - collection and destruction of fallen infected acorns before the larvae emerge from them, careful sorting of acorns during harvesting, temporary storage of collected acorns in cold rooms with wooden floors. In fruit-bearing plantations in harvest years, grazing of pigs is recommended until healthy acorns begin to fall. It is also necessary to attract and protect insectivorous hollow-nesting birds (nuthatch, pika, titmouse).

Weevils are largest family in the living world, there are, according to some estimates, 70,000 species. BUT
all chordate animals - all animals, birds, fish and others - only 55,000. The whole type of chordate animals “fits” in one family of elephants. Such diversity is simply hard to imagine. Unique diversity is created by variation within a similar organization. Yes, kind Apion- small weevils "with a pinhead", however, without going beyond Moscow, you can collect 600-700 species, and with the region - so for 2000. And this is just one genus.

In fruits and seeds live larvae of weevils-fruit-bearers from the genus Curculio, to which
the acorn weevil also applies - length 5-8 mm, from dark brown to black, elytra
covered with grayish-yellow hairs, with a very long "trunk" - the rostrum. Antennae, like
all weevils, cranked. Years of beetles in late April-May - and until September. Until mid-summer, beetles feed additionally, eat young leaves, shoots and flowers. different trees- oak, birch, linden, etc. Then they flock to fruit-bearing oaks. Females eat a long passage in the stomach, in which they lay eggs one at a time, less often several. Several eggs per acorn are laid when there are few acorns. The egg stage lasts a week or two. Damaged acorns, not ripe, fall off.

The development of the larva lasts three to four weeks, then it gnaws a hole in the acorn shell and goes deep into the soil, where it pupates. In August, young beetles appear, but they do not emerge from the soil, they hibernate. Only in spring they appear on the surface. Sometimes some larvae are in diapause and hibernate for two winters. Therefore, the duration of the development of beetles is different. Most often, however, the generation lives for two years, the larvae hibernate the first winter, the beetles hibernate the second.

First of all, it must be said about the most noticeable detail - the "nose" of these beetles. It's not a nose
of course, but the head elongated into a thin tube, and on the top of this tube are the same mouthparts as in all beetles. Why eat with such a thin apparatus, if you can, like other beetles, "eat in your mouth"?

In weevils, the "trunk" is a replacement for the ovipositor. Elephant females have a soft ovipositor, and eggs should
lay in very hard substrates - for example, fruits. Here is an acorn weevil laying
them in the stomach. To do this, the female gnaws with her thin long nose passage in the hard shell of the stomach. The beetle, working with its jaws, clings with all its might to the smooth surface of the acorn.
Short middle and front legs do not reach the surface of the acorn, so the beetle stands on its hind legs, resting on the "floor" with its proboscis. If the female slips, her legs will break off, the “trunk” immersed deep in the acorn will spring up and ... the female will hang upside down on her own nose above the surface of the acorn - her legs cannot be reached. Waiting for her then painful death on your own nose.

If everything goes well, the female, after 8 hours of continuous work, safely withdraws from
of the “trunk” hole made, then it turns around and places the egg with a soft ovipositor in
the “mine” made by the mouth parts.

It seemed like an extremely strange device. All other insects get by somehow - either
have a hard ovipositor, or choose softer places for oviposition. But weevils have a "nose"
serves as a functional replacement for the ovipositor - and only so. There is indirect evidence that this explanation is not fiction. There are many short-proboscis weevils - well, at least
light green Chlorophanus viridis, usual with us. Their head is very weakly elongated or even completely “snub-nosed” - and at the same time, females always have a hard ovipositor, with which they cut a hard surface in order to then lay eggs in it. And so it always is - either the nose is long, or the ovipositor is hard.

This means that this is how everything is arranged in this group ... But at the same time, let's not forget that the nose instead of the ovipositor serves only females, and males wear a huge schnobel “for beautiful ladies". Grasshopper has fat
females are forced to have a sound apparatus that they do not use - males need it, and they "inserted" the sound apparatus into the development of females. In the family of weevils, the females "revenge": the selection pressure towards the acquisition of the rostrum was so strong, the "nose" was so firmly imprinted in the embryonic development of these beetles that both males and females receive it from them. They pulled the nose of the males, one might say.

Many larvae of weevils feed on the leaves of plants, like those of leaf beetles. But they “diverge” from leaf beetles: leaf beetle larvae usually live openly and feed on the surface of the leaf, and weevil larvae more often eat through passages inside the leaf. Of course, weevils also have other types of food. Other elephants eat plant flowers, especially their pistils and stamens, many eat seeds (elephants Larinus live only in the inflorescences of Compositae), many weevils feed in the soil on the roots in the manner of the beetles ( Phyllobius, Polydrosus) - in a word, weevils regularly play all possible "roles" of herbivorous beetles.


During courtship, the males of some elephants quietly “squeak” and “chirp”, charming the females. Alone
of them make sounds, rubbing the elytra on the abdomen, while others prefer, on the contrary, to rub
thigh on the edge of the elytra, like a locust. The tricks of elephants extend even further: most
species, frightened, immediately tuck their legs and "dead" fall into the grass, where to find them -
hard work. It lies motionless, the color is discreet... Many other beetles also pretend to be dead - pretenders, peanuts, dead eaters... But there are also "bold" creatures: seaside
Metialma signifera in case of danger, it immediately flies away, “lying on the wing” easily, as if it were not a beetle, but some kind of nimble fly. The vast majority of weevils are diurnal beetles, but even here
there are exceptions: Deracanthus inderiensis, living in the sands of Kalmykia, is active at night when it is not so hot.
http://www.zin.ru/Animalia/Coleoptera/images/alter/deracanthus_odontocnemus_sp.jpg
(I give a link, because the photo is large - but the beetle is beautiful)

Larvae of weevils from the genus Balanobius ( Balanobius pyrrhoceras) live in galls - special
growths of plant leaves that hide insect larvae. Gall formation - complex
the process of interaction between an insect larva and a plant, from which both receive a certain
benefit, and a gall is built by the plant in response to the release of certain chemical substances.

Usually galls build larvae of flies and hymenoptera. Beetles usually do not form galls, and
Balanobius larvae live in foreign galls. The female lays eggs in the galls of the galls on the oak, and the weevil larva gets a ready house and table. In the same way, a larva of a related species
Balanobius salicivorus lives in sawfly galls ( Pontania) on willows, and some small weevils from the genus Apion and Brachomyx pinati live in galls on pine needles.

Some species lay unfertilized eggs, from which only females hatch. Such
the phenomenon is called thelytoky, in contrast to arrhenotoky, which is common, for example, in bees, in which, on the contrary, male drones are hatched from unfertilized eggs.

The most common in Russia is the pine weevil Hylobius abietis, Smolevka
Pissodes pini, large willow weevil Lepyrus arcticus, catkin weevils
notaris. Some species are pests in warehouses. From such bad bugs
the most famous rice weevil Sitophilus granarius- a common stock pest,
who lives about the same as a black beetle-hrushchak.

There are also weevils living together: rotten Cossonus linearis do not diverge from
"tasty" bitch, the females lay more and more new eggs, the "colony" will reach the number of several
thousand copies until the twig is eaten clean. However, the miracles of the elephant hostel are still
ahead...

The oak fruit has an outgrowth on its head that looks like a proboscis. This proboscis is nothing more than a beetle's mouth apparatus with powerful and strong jaws, like a diamond.

It is because of the proboscis that this beetle is called an elephant. It is also called acorn weevil.

The habitat of the oak fruit

Oak fruits - quite large group insects, there are more than 30 thousand species. They live in areas with mild winters, while too hot climates are also not suitable for them. In this regard, oak fruits will be most widely used in Europe and the European part of our country. In addition, the acorn elephant feels good in southwest Asia and in North Africa.

These beetles live in forests, gardens, fields and swamps. Almost all oak fruits are pests because they eat plants, including fruit trees and cultivated ones.

Lifestyle of acorn weevils

These beetles are no different large sizes, their body length is about 5-8 millimeters, the proboscis has the same length. oral apparatus equipped with teeth of a gnawing-drilling type, with the help of which the beetles eat, and also gnaw out minks for their offspring. Strong teeth allow for drilling holes in tough acorns. The female lays her eggs at the bottom of the acorn.

In summer and spring, acorn weevils eat young shoots, and in autumn they look for oaks.

Reproduction of oak fruits

Acorns are necessary for fruit-bearing because they contain a large number of nutrients. To get to these substances, the progenitor has to drill 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.

First, the female makes a drilling point, and then around it describes one or another semicircle. The surface of the acorn is rather 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 females who died in such an absurd way.

If the work is completed successfully, the female turns and, with the help of a red-colored ovipositor, lays her eggs in the depths of the acorn.

Over time, legless larvae form from eggs, a white-yellow body, which resembles a sickle in shape. For the development of the larva in a secluded house there is everything necessary: ​​food, warmth, safety.

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 appears from the chrysalis.

With the first warmth, insects begin to fly, and life cycle repeats again. Most in the development of the oak fruit beetle, a two-year generation takes place, during which the larvae overwinter in the first year, and adult beetles in the second year.