Weevils, or elephants (genus Curculionidae) - the largest family of beetles, numbering more than 70,000 species, most of which inhabit the tropical regions of the Earth. Their Curculionidae (snout beetles), for which they were called. Most weevils develop from plant tissues within them. Less larvae feed on the outside of the leaf or flower (Hyperini, Cionini). Many developing in the soil, feeding on plant roots, rarely - litter. Few people eat rotting wood (Cossoninae). The vast majority of species associated with herbaceous vegetation, the majority of dicotyledons. Links to monocotyledonous slightly less with spore even less.
In the world fauna has more than 70,000 species, of which Russia about 5000 species.
Usually there are representatives of the length from one to 30 mm, and in the tropics to 50 mm. The body shape of weevils is very diverse, it is: almost cylindrical rod (Lixus). elongated flattened (Larinus, Cionus), orthorhombic form (Curculio, Trigonocolus), convex hemispherical (Orobitius), globular (Ceutorhynchus) or pear (Anthonomus, Catapionus). Color covers varies from yellow, brown to black, sometimes with patches of lighter or darker cuticle on pronotum and elytra, or yellow, reddish-brown legs, a body with less copper, metallic green or blue tint. The upper part of body naked or covered with hairs, voloskoobraznymi scales or broad scales, often with rows of longer setae on the elytra, with white, yellow, brown or black spots or bands, which are beetles are well masked by soil and vegetation. Sometimes the body of beetles covered earthen crust, while the species living near the water is thick, mostly dull glazurevidnye flakes of brown shades.
Males are smaller than females and have a shorter rostrum, its lower bending and greater width than that of females in male antennae are located closer to the head, eyes another form, the elytra less convex, abdominal sternites bent in the middle.
The larvae of weevils are predominantly sickle-shaped body and usually has a white or yellow in color. The development of the larvae may take place in the stems of herbs, roots or feed on litter. Weevils primarily herbivores, less fitosaprofagi. They eat almost all kinds of plants, but are more concerned with bipartite than monocotyledonous. The larvae mine the leaves, their development occurs in fruits, flowers, buds, petioles, young twigs and branches, gnaw through tunnels under the bark, at different depths in healthy and in dried or rotten trees.
Adult beetles often feed on green parts of plants, pollen, fabric flowers or developing fruit. Species such as the genera and Cryptorrhynchus Cossonus gnaw wood, covered with mushrooms and eat the mycelium of fungi. Many wetland weevils, such as the genera Bagous and Ceutorhynchus, fed tissues of aquatic plants, even under water. Weevils are closely linked with certain types of food plants. Polyphagia greater among shirokohobotnyh, ie at more advanced in evolutionary terms.
Many soil weevil larvae prefer shallow roots of plants, including shrubs and trees. Some, for example representatives of the genus Emphytus (Otiorhynchus), damaging the roots of seedlings and saplings. Most damaged seedlings and saplings unwell, are stunted, although over time restore the damaged plant roots and continue to grow. Bring greater harm to the adult beetles weevils, which can destroy seedlings of tree and shrub species, browse the seedlings and saplings, and their kidneys and even the bark of one or two summer seedlings often leading to death.
The larvae can damage field crops, vegetables, garden, forestry and industrial crops and plant stocks, developing in the tissues, fruits and seeds. There are also serious pests. In addition to pests, there are several species of weevils used in biocontrol of weeds.