At present, probably about 1.5 ... 2 million different species of insects live on the globe. In order to understand this huge variety of forms, it is necessary to systematize them, that is, to establish family relationships between various types, combine them according to the degree of kinship into subordinate systematic categories, or taxa, and arrange these categories in a certain ordered system. These tasks are performed by one of the branches of biology called systematics. The task of systematics is not only the definition (diagnosis) and an accurate description of the species, but also the classification, i.e. the creation and correct location of various taxa in a single natural system of the animal world. Thus, classification is a synthetic stage of taxonomy.
The concept of the form
The main taxonomic unit in taxonomy is a species, which, according to G. Ya. Bei-Bienko (1971), is an integral system of similar individuals occupying a certain geographical area and, when crossed, give fertile offspring that retains similarity with their parents. Related species are grouped into genera, genera into families, families into orders, and orders into classes. As applied to insects, the enumerated number of taxa is insufficient. In order to better reflect the specifics of family relations between individual groups insects, use a number of additional systematic units. In general, the following series of taxa are used in the classification of insects: class, subclass, infraclass, division, superorder, order, suborder, superfamily, family, subfamily, tribe, genus, subgenus, species, subspecies.
To designate all taxa, international, Latin nomenclature is used, and for the species it is binary, i.e., it consists of two words - the generic and specific names: for example, Pieris brassicae L. - cabbage white (letter L. abbreviated the name of K. Linnaeus - the scientist who first described this species); Pieris rapae L. - turnip whitefish; Pieris napi L. - blueberry whitefish, etc. The genus of whitefish (Pieris), together with other genera (Colias, Aporia, Euchloe, etc.), is united in the family. whites - Pieridae. In this case, the Latin name of the family is always formed from the root of the name of the type genus (in this case, Pier) and the ending - idae (ending plural meaning "similar"). Uniform endings have also been introduced for other taxa. For example, the names of orders of primary wingless insects end in ura (oura - in Greek tail), orders of winged insects - in ptera (ptero, pterus - wing), superorders and superfamilies - in oldea, subfamilies - in inae, etc.
The view is not indivisible. One of the properties of a species is its existence as a system of intraspecific forms. The main intraspecific forms include subspecies, ecotype and population.
Subspecies, sometimes also called a geographical race, represents a change in species associated with a mismatch in the conditions of existence in various parts area of its distribution (range). Subspecies are stable, but often unsharp morphological features, and sometimes differences in the annual cycle and environmental responses. Trinary nomenclature is used to designate subspecies; for example, the migratory locust (Locusta migratoria L.) has a number of subspecies: the main subspecies is L. migratoria migratoria L., the Central Russian locust is L. migratoria rossica Uv. et Zol., eastern migratory locust - L. migratoria manilensis Mey. and etc.
Ecotype- an ecological race that occurs when a species settles in new habitats that differ markedly in conditions external environment. Ecotypes, as a rule, are not morphologically isolated and differ only in ecological and physiological reactions (they have different threshold points of the photoperiodic reaction, change food specialization, etc.). For example, the mallow moth, whose caterpillars in the republics Central Asia feed on wild mallows and have no economic importance, when moving to Transcaucasia, it switched to cotton, formed a special cotton form and became one of the serious pests of this crop.
population is a group of closely related individuals of the same species, forming separate settlements, and is the basic unit of existence of a species in nature.
Species are unequal among themselves in their structure. Thriving, widespread species that have a complex set of intraspecific forms - subspecies, ecotypes, populations, are called polytypic, while species with a limited range, represented by only a few, and sometimes only one population, are called monotypic. An example of a polytypic species is the aforementioned migratory locust, a monotypic species is the wingless grasshopper steppe stalk (Sago pedo Pall.).
2. Insect classification
1. A section of biology that develops a theory of classification and recognition of animal and plant organisms.
2. The most important task of systematics is to establish related relationships between various organisms and combine them according to the degree of kinship into subordinate systematic categories, or taxa, on this basis, a classification of each specific group of organisms is developed.
Class(classis)
Subclass (subclassis)
Infraclass (infraclassis)
Division
Superorder (superordo)
Detachment(ordo)
Suborder (subordo)
Superfamily (superfamilia)
family
Subfamily (subfamilia)
Tribe (triba)
Genus(genus)
Subgenus (subgenus)
View(species)
Subspecies
Insect classification
Subclass lower, or primary wingless - Aprerygota
A. Infraclass entognathous - Entognatha
1) Detachment of protura, or bessyashnye - Protura
2) Podura detachment, or springtails - Podura
3) Detachment diplura, or two-tailed - Diplura
B. Infraclass tizanur - Thysanurata
4) Detachment of tizanura, or bristletail - Thyzanura
Subclass higher, or winged - Pterugota
Department with incomplete transformation - Hemimetabola
Superorder ephemeroid - Ephemeroidea
5) Mayfly squad - Ephemeroptera
Superorder Odonatoid - Odonatoidea
6) Dragonfly detachment - Odonatoptera
Superorder orthopteroids - Orthopteroidea
7) Squad of cockroaches - Blattoptera
8) Mantis squad - Manteoptera
9) Order termites - Isoptera
10) Stonefly Squad - Plecoptera
11) Embiy Squad - Embioptera
12) Grilloblattida detachment - Grylloblattida
13) Squad of stick insects - Phasmatiptera
14) Order Orthoptera - Orthoptera
15) Detachment Hemimerida - Hemimerida
16) Order leather-winged - Dermaptera
17) Zoraptera detachment - Zoraptera
Superorder hemipteroids - Hemipteroidea
18) Squad of hay eaters - Psocoprtera
19) Squad of lice - Mallophaga
20) Louse Squad - Anoplura
21) Order Homoptera - Homoptera
22) Detachment of bedbugs - Hemiptera
23) Order of thrips - Thysanoptera
Superorder coleopteroids - Holometabola
24) Order of beetles - Coleoptera
25) Windwing order - Strepsiptera
26) Detachment Neuroptera - Neuroptera
27) Camel Squad - Raphidioptera
28) Large-winged order - Megaloptera
Superorder mekopteroidnye - Mecopteroidea
29) detachment of scorpion flies - Mecoptera
30) Order of caddisflies - Trichoptera
31) Butterfly Squad - Lepidoptera
32) Order Hymenoptera - Hymenoptera
33) Flea Squad - Aphaniptera
34) Order Diptera - Diptera
Insects are one of the most numerous classes of the animal world. They have their own structural and lifestyle features that distinguish them from other animals. Of the existing classes of invertebrate animals, insects are distinguished by complex neuropsychic activity, which is clearly expressed in social insects - bees, wasps, termites, ants.
Insects will fall into the phylum Arthropods, which, in addition to them, includes several more classes, the main ones being Arachnids, Crustaceans and Millipedes. In addition to insects themselves, representatives of other classes are often considered as pests of plants (Table 1.2).
The superclass Insects is divided into two classes - Hidden jaws And open jaw- and 34 detachments, of which three belong to the first class, and the rest - to the second. The first class includes Springtails, Sewingless, Twintails. These are small insects without real transformation. Some of their representatives sometimes harm plants, mainly seedlings or greenhouse and indoor flowers.
All species of interest to us belong to the second class - Open-jawed (Ectognata). They are divided into subclasses Primary wingless (Apterygota) (Bristletails) and Winged (Pterygota) (all others). The subclass Winged includes two infraclasses: Ancient-winged (Palaeoptera), which includes the orders of Mayflies and Dragonflies, and New-winged (Neoptera), which includes all other orders of insects. The main ones are as follows.
Order Orthoptera. Insects with gnawing mouthparts and often hopping hind legs. The forewings are usually narrow, leathery, the hindwings are reticulate and fan-shaped. Representatives of the detachment (medvedka, grasshoppers, locusts, fillies) harm various types of plants.
Detachment Leather-winged, or Earwigs (Dermaptera). The oral apparatus is gnawing. Forewings strongly shortened, leathery; hindwings wide, membranous. Sometimes the wings are missing. At the end of the abdomen there are cerci in the form of pincers. They harm ornamental plants in greenhouses, conservatories and gardens. The representative is the common earwig.
Order Homoptera. The mouth apparatus is piercing-sucking, in the form of a proboscis, sometimes much longer than the body. The wings are membranous, at rest folded roof-like. There are many pests of ornamental plants in the detachment: cicadas, psyllids, whiteflies, aphids, mealybugs, scale insects. Often serve as carriers of viral plant diseases.
Order Hemiptera, or Bedbugs (Heteroptera). The mouth apparatus is piercing-sucking, in the form of a segmented proboscis, bent under the body. The front wings are semi-rigid, the hind wings are membranous. All bugs emit a specific smell. Among them there are dangerous plant pests and predators that feed on phytophages.
Order Fringed, or Thrips (Thysanoptera). Small insects 0.5-5.0 mm long. The oral apparatus is piercing-sucking. There are two pairs of wings, narrow, membranous, with long hairs along the edge. Dangerous pests of ornamental plants. Representatives of these units develop with incomplete transformation.
Order Coleoptera (Coleoptera). The most numerous order of insects, including up to 250 thousand species. The oral apparatus is gnawing. The wings are heterogeneous: the front ones are rigid (elytra or elytra) serve to protect the second pair of membranous wings. Larvae with a well-pronounced head, with three pairs of pectoral legs or legless. The doll is free.
Ground beetle family(Carabidae). Beetles of various sizes with filiform antennae and running legs. Larvae with three pairs of thoracic legs. Most species are predators, occasionally harming plants (corn beetle). The beetle-beetle destroys a huge number of butterfly caterpillars.
Nutcracker family(Elateridae). The body of the beetles is elongated, the posterior angles of the pronotum are drawn back, the prothorax has a rigid process directed backwards and inserted into a depression on the mesothorax. Beetles that have fallen on their backs jump, making a characteristic click. Antennae serrate or comb. Click beetle larvae are yellowish-brown, hard, called wireworms, and have three pairs of underdeveloped legs. They live in the soil, feeding on the roots of plants, damaging tubers, bulbs of flower crops.
Zlatka family(Buprestidae). Beetles of various sizes with a flat, elongated body, tapering towards the posterior end. The head is retracted into the prothorax; antennae short, serrated. The color is often metallic, shiny. The larvae are white, flat, with an elongated body and a strongly expanded prothorax.
Ladybug family(Coccinellidae). The body is hemispherical. The beetles are brightly colored - black, red, yellow with red and black spots. Beetles and larvae are predators, but there are herbivorous forms.
Mustachio family(Cerambicidae). Beetles with an elongated body. Antennae filiform, serrated, bristle-shaped, sometimes pectinate, longer than half of the body. The larvae are white, with an elongated flattened body, slightly tapering towards the posterior end, with short pectoral legs or with calluses. Some are very harmful to ornamental plants. Representatives - poplar barbel, willow barbel, oak barbel.
Leaf beetle family(Chrysomelidae). Beetles with a short convex body. Antennae shorter than half the body, filiform, beaded. Legs walking, sometimes jumping. The larvae are small and have three pairs of thoracic legs. Both larvae and beetles often harm ornamental plants. Representatives - Colorado beetle, viburnum and poplar leaf beetles.
Weevil family(Curculionidae). The head is elongated into a rostrum of varying length and thickness. The body is elongated; antennae crank-shaped, walking legs. Larvae are white, fleshy, curved, headless, legless. Representative - furrowed weevil.
Family(Attelabidae). The beetles are similar to weevils, but have a metallic shiny color, the antennae are not articulated, with a short anterior segment. Often harmful to ornamental plants. The representative is a polyphagous trumpeter.
Family Bark beetles(Scolytidae). Small beetles with valky cylindrical body. Maximum length body 9 mm. Color from brown, brown to black, shade matte or shiny. Antennae geniculate-clavate. Larvae are white, curved, legless. The pupae are open and white. Dangerous pests of trees, often leading to their death. Representatives - birch sapwood, bark beetle-typographer, ash beetle.
Family Lamellar(Scarabaidae). Beetles of medium and large sizes, cranked antennae, with lamellar club. The front legs are semi-digging. Elytra cover the entire abdomen or the last segments remain open. Larvae are white, s-curved, with three pairs of well-developed pectoral legs. The last abdominal sternite bears rows of spines and setae, by which the species can be identified. Representatives - May, June Khrushchev, bronze.
Order Lepidoptera, or Butterflies (Lepidoptera). The oral apparatus is sucking, sometimes it is absent. Wings two pairs, membranous-scaly. Caterpillars with a well-developed head, three pairs of thoracic legs and 2 to 5 false ventral legs. There are many ornamental pests in the detachment that damage all parts of the plant. Representatives - gypsy moth, willow volnyanka, winter moth.
Family Scoops, or Nights(Noctuidae). The body of butterflies is covered with thick hairs. Antennae filiform or bristle-like, pinnate in males. The forewings are narrow, the coloration is often inconspicuous. Caterpillars with 3-5 pairs of false ventral legs, glabrous or with short sparse hairs. Representatives - pine scoop, polyphagous scoop.
Moth family(Geometridae). The body is slender, narrow, the front wings are triangular, wide. In females of some species, wings are absent or shortened. Caterpillars have two pairs of false abdominal legs, so they move by bending the body in a loop, hence the name - moths. Representatives - pine moth, winter moth.
Family Cocoonworms(Lasiocampidae). butterflies medium size or large, with a massive body covered with thick hairs. The forewings are larger than the hindwings. The mouth apparatus is reduced (butterflies do not feed). Antennae pinnate in males and combed in females. Caterpillars with three pairs of false ventral legs. Pupae in a loose cocoon. Some species are harmful to ornamental plants. Representative - ringed silkworm.
Volnyanka family(Lymantriidae). Butterflies with a massive body covered with hairs look like cocoonworms. Caterpillars with 5 pairs of false abdominal legs, warts covered with hairs on the body. Representatives - golden tail, willow volnyanka.
Corydalis family(Notodontidae). Butterflies of medium and large size, active at night. The body is massive; the wings are relatively narrow, at rest laid in a roof-like manner. Caterpillars are naked or covered with hairs, with 5 pairs of false ventral legs. The representative is a silver hole.
Belyanki family(Pieridae). Diurnal butterflies of medium size, painted white, yellow or yellow-red; wings are raised at rest; antennae club-shaped. Caterpillars are naked, with 5 pairs of false ventral legs. Representative - hawthorn.
Family Ermine moths(Hyponomeutidae). Small butterflies with white front wings and black spots on them. Forewings comparatively narrow, widened towards outer margin; hindwings dark, fringed. Caterpillars are naked, light, with sparse hairs. They live in colonies on hardwoods, braiding leaves, branches and trunks with a dense white cobweb. They pupate in white cocoons with pointed ends. Representatives are euonymus and bird cherry spider moths.
Family Carpenters(Cossidae). Large night butterflies, the body is covered with dense hairs. The forewings are larger than the hindwings. The oral organs are reduced. Caterpillars are naked, with sparse hairs, with 5 pairs of false ventral legs. Damage to tree branches and trunks. Representatives - corrosive woodworm, willow woodworm.
Glassware family(Sessidae=Aegeriidae). Small and medium butterflies with transparent wings, so they look like hymenoptera. The wings are folded roof-like. The body is slender, the antennae are filiform. Caterpillars whitish, glabrous, with sparse hairs, dark head, with 5 pairs of false ventral legs. They live under the bark, in the trunks of trees and shrubs. Representative - poplar glass.
Order Hymenoptera (Hymenoptera).
Family True horntails(Siricidae). Medium and large insects with an elongated cylindrical body, long filiform antennae, gnawing mouthparts. The hindwings are shorter than the forewings; at the end of the abdomen there is a horn-shaped process; females have a real ovipositor. Larvae are white, cylindrical, with short thoracic legs, with a sharp horn-like stepped process at the end of the body. Representative - birch horntail.
Family True sawflies(Tenthredinidae). Numerous family, subdivided into subfamilies. Insects of different sizes and colors. The head is well developed; mouth apparatus gnawing; antennae varying in length and shape, sometimes pinnate in males. The wings are well developed, the hind wings are smaller than the front ones. The females have a short, serrated ovipositor. The larvae are brightly colored, with three pairs of pectoral and 6-8 pairs of false ventral legs. Representatives - spruce sawfly, red pine sawfly.
Order Diptera (Diptera). This includes flies and mosquitoes. The wings are membranous, only the first pair is developed, the second pair is turned into halteres. The oral apparatus is cutting, varnishing. The larvae are often legless with a reduced head. The pupa is free, in puparia. Some species are harmful flower crops. Representatives - narcissus fly, onion fly.
Representatives of the above groups develop with complete transformation.
Knowledge of taxonomy is necessary for proper diagnosis - identification and identification of malicious and beneficial insects. In the class of insects, 34 orders are distinguished, the most significant of them in agricultural practice are presented below (Protection of plants from pests, 2002).
Class Insects - Insecta. Subclass Primary wingless - Arterygota.
A small group of insects with a complete absence of wings retain the vestiges of ventral limbs. Mostly small, secretive insects, saprophages, herbivorous or carnivorous. Representatives: springtails, bristletails.
Subclass Winged - Pterygota.
Includes the vast majority of insects. Wings, as a rule, are developed, and in case of absence, signs of structure associated with wings are preserved. There are no abdominal limbs. Orders of winged insects are combined into two large divisions, differing in the type of development.
Department Insects with incomplete metamorphosis - Hemimetabola. Order Orthoptera - Orthoptera.
Large and medium sized insects. The body is elongated, often laterally compressed. Antennae long, usually filiform or setiform. The oral apparatus is gnawing. The front wings are elongated-rectangular, leathery. Hind wings wide, fan-shaped, membranous. Venation is reticulate. Hind legs jumping. The females have an ovipositor. Males have developed vocal apparatus. They live mainly in grassy and tree-shrub vegetation. Many are agricultural pests. The detachment is divided into suborders: long-whiskers - grasshoppers, crickets, bears and short-whiskers - locusts.
Order Hemiptera or bugs - Hemiptera.
Order Homoptera - Homoptera.
Diverse in appearance, mostly small insects. The antennae are usually filiform or setiform. The oral apparatus is piercing-sucking. Both pairs of wings are membranous, less often the forewings are leathery. The forewings are more developed than the hindwings. The venation is membranous. Often there are wingless forms. Some species have developed jumping legs. Many have wax secreting skin glands. Most live on grassy and woody vegetation. All homoptera are herbivores. There are 5 suborders in the detachment: cycads, fleabane, whiteflies, aphids, coccids (worms and scale insects). Each of them has agricultural pests (dark cicada, apple sucker, greenhouse whitefly, pea aphid, comma-shaped scale insect).
Order Fringed-winged or thrips - Thysanoptera.
Small insects with an elongated narrow body. Antennae short filiform. The mouthparts are piercing-sucking with a short proboscis and three piercing setae. The wings are elongated, very narrow, membranous, fringed. Venation membranous, poorly developed. Walking legs, with small retractable suckers at the ends of the legs. Females often have an ovipositor. Most thrips are herbivorous (wheat thrips, linen thrips, tobacco thrips).
Insects with incomplete metamorphosis also include orders of mayflies, dragonflies, cockroaches, praying mantises, earwigs, termites, stick insects, lice, and others.
Order Insects with complete metamorphosis - Holometabola.
Order Coleoptera or beetles - Coleoptera.
Sizes from small to large. The oral apparatus is gnawing. Powerful protective rigid forewings (elytra). The hind wings are elongated, membranous with membranous venation. In flight, only the rear wings work. In addition to normal, walking and running legs, some representatives have swimming, digging and jumping legs. Larvae of diverse structure - worm-like and campodeoid-shaped, with or without legs. Most pupae are open. There are many predators in the detachment that destroy harmful insects (most ground beetles and ladybugs, rove beetles). Many different agricultural pests are known in families: lamellar (bread beetles, may beetles), click beetles (striped, sowing), dark beetles (sand lingering beetles, flour beetles), barbels (black spruce, sunflower), leaf beetles (Colorado potato beetle, bread, beet and cruciferous fleas, piavitsa), grains (pea, bean), weevils (beet, nodule, apple flower beetle), etc.
Detachment Reticulate - Neuroptera.
Diverse, medium-sized insects with an elongated thin body and large membranous wings with reticulate venation. The oral apparatus is gnawing. Most terrestrial, moderate flight. All lacewings are predators and can be beneficial by destroying pests. Most famous representatives: lacewings, antlions.
Order Lepidoptera or butterflies - Lepidoptera.
Insects with a relatively thin body and large membranous wings with scaly pubescence. Sizes from small to large. The oral apparatus is sucking. The forewings are slightly more developed than the hindwings. The venation is membranous. Legs are simple, walking. Larvae caterpillar-like, pupae covered. Adults fly actively, most feed on nectar. Most caterpillars are terrestrial, less often soil caterpillars, feed on various parts of plants. The largest number of pests is known in the group of families of moths (clothes, grain, apple, cabbage moths), leafworm families (apple and pea codling moths), moths (meadow and stem moths), whites (cabbage and turnip), cocoonworms (ringed silkworm), moths (winter), volnyanka (gypsy moth), scoops (winter, gamma, grain, cabbage).
Order Hymenoptera - Hymenoptera.
Order Diptera - Diptera.
Main tasks. Insects are the most numerous group of animals in the world. Currently, there are 1.5-2 million species. In order to understand this huge variety of species, it is necessary to systematize them, that is, to establish kinship relationships between different species, combine them according to the degree of kinship into subordinate systematic groups, or taxa, and arrange these groups in a certain ordered system. For this, special sections of entomology serve - the taxonomy and classification of insects.
The main task of insect taxonomy is to divide the vast diversity of individuals that exist in nature into easily recognizable groups, to identify diagnostic characters for these groups, and to establish permanent differences between similar groups. The task of classification is the creation and correct arrangement of various taxa in a single system of the animal world. If systematics represents the analytical stage of the work of a taxonomist, then classification is its synthetic stage.
The ultimate task of taxonomy and classification is to create not just a system, but natural system animal world. Therefore, if earlier, when determining the relationship of organisms, taxonomists were based almost exclusively on morphological characters, then modern taxonomists comprehensively use all available criteria, up to molecular and cellular ones.
The concept of the form. The main taxonomic unit in taxonomy is a species, which, according to the definition of G. Ya. Bei-Bienko (1980), is a separate integral system of similar individuals that own a certain geographical area and, when crossed, give fertile offspring that retain similarities with their parents. If we compare this modern definition with. the one given to the mind by K. Linnaeus in the 18th century. (a species is a collection of individuals that differ from each other no more than children from parents), then a simplified interpretation of the latter is striking only by morphological criteria. At present, in addition to morphological (similarity of individuals), when characterizing a species, geographic (settlement of a certain part of the territory of the earth), physiological (fertile offspring when crossing), genetic (preservation of similarity with parents) and ecological (holistic system of similar individuals, i.e. e. polytypicity of the species) criteria.
intraspecific forms. Intraspecific forms arise under the influence of environmental variability. In accordance with the peculiarities and depth of this influence, a number of specific forms arise. In political flourishing species this internal structure more complex than those of monotypic, less prosperous and without subspecies. The main intraspecific forms include subspecies, ecotype and population.
A subspecies, sometimes also called a geographical race, represents a change in species associated with a mismatch in the conditions of existence in different parts of its range. Subspecies differ from each other in stable, but often indistinct morphological characters, and often in differences in the annual cycle and ecological reactions. In places where populations meet, the differences between subspecies are smoothed out and disappear. Such a gradual transition from one geographical form to another is called clinal variability. If a changeable row, or wedge, is tied to a narrow area with natural obstacles (mountains, water sources), then the subspecies are well separated; if the wedge is strongly stretched over a vast territory, then, in essence, there is no new subspecies, but there is only a gradual change in characters in the widespread subspecies.
To designate a species, a binary nomenclature is used, consisting of two words - genus and species. For example, Locusta migratoria L. is a migratory locust, and the letter L. is an accepted abbreviation of the name of a scientist, in this case K. Linnaeus, who first described this species. Trinary nomenclature is used to designate a subspecies. For example, five subspecies are known for the migratory locust: L. migratoria migratoria L. is the main subspecies, L. migratoria rossica Uv. et Zol. - Central Russian locust, L. migratoria gallica Rem. - Western European, L. migratoria migratoroides Reich, et Fairm - African, L. migratoria manilensis Mey. - Eastern migratory locust.
Ecotype - an ecological race that occurs when a species settles in new habitats that differ markedly in environmental conditions. Ecotypes, as a rule, are not morphologically isolated and differ only in ecological and physiological reactions, i.e., they have different threshold points of the photoperiodic reaction, have different cold resistance, change food specialization, etc. Thus, the mallow moth, whose caterpillars in the republics of Central Asia feed on wild mallows and have no economic importance, when moving to the Transcaucasus, it switched to cotton, formed a special cotton ecotype and became one of the serious pests of this crop. Blood aphids introduced into early XIX in. from North America to Europe, populated an apple tree in a new place and lost the ability to develop on its primary host, the American elm.
A population is a collection of individuals of the same species that occupies a certain area of a territory for a long time and reproduces itself over a period of time. more generations. A population is the basic unit of a species' existence.
Main taxa and their designation. Related species are grouped into genera, genera into families, families into orders, and orders into classes. As applied to insects, this series of taxa is insufficient. To more fully reflect the specifics of kinship relations between individual groups of insects, a number of additional systematic units are used. In general, the following series of taxa are used in the classification of insects: class, subclass, infraclass, division, superorder, order, suborder, superfamily, family, subfamily, tribe, genus, subgenus, species, subspecies.
To designate all these taxa, except for Russian, international Latin nomenclature is used, and, as noted above, it is binary for a species, and trinary for a subspecies. Close genera, for example, the already mentioned genus Locusta, as well as the genera Acrida, Dociostaurus, Calliptamus and many others, are united in the family of true locusts - Acrididae. In this case, the Latin name of the family is always formed from the root of the name of the type genus (in this case, Acrid) and the ending - idae, representing the plural ending, denoting "similar".
Uniform endings have also been introduced for other taxa. Thus, the names of orders of primary wingless insects end in yoke (oiga - in Greek tail), orders of winged insects - in ptero (ptero, pterus - wing), superorders and superfamilies - in oidea, subfamilies - in inae, etc.
At present, the class insects is usually divided into two subclasses, which, according to G. Ya. Bei-Bienko, include 34 orders.
96. Class Insects: general characteristics, systematics, medical significance. Epidemiological classification of insects with examples.
Type Arthropoda Arthropoda. Subtype Tracheal-breathing Tracheata Class Insects Insecta
This is the most numerous class of animals in terms of the number of species. Their total number reaches 1 million.
The body of insects is divided into 3 sections: head, thorax and abdomen. The head segments (there are 5 of them) carry 4 pairs of limbs: the 1st pair - shackles (antennas), the 2nd and 3rd pairs - the jaws (the lower ones - carry sensitive palps), the 4th - the lower lip (fused lower jaws).
Insects, depending on the lifestyle and mode of nutrition, can have different types of mouth apparatus: gnawing, piercing-sucking, licking, etc. There is 1 pair of simple or compound eyes on the head.
Insects are six-legged animals that develop cuticular folds - wings - on the thoracic segments. Each segment of the chest corresponds to a pair of walking legs, which consist of 5 segments. The segments of the abdomen of the limbs are not borne, with the exception of those modified into copulatory appendages (cerci, styli).
Insects have very complex musculature that enables very fast movements. Chitin carries appendages - hairs, glandular bristles, odorous and poisonous glands.
Of the features internal structure it should be noted a more progressive structure of the central nervous system: the fusion of the head ganglia into the brain, consisting of 3 sections: two hemispheres, visual lobes and mushroom bodies.
A feature of the digestive system is the presence of salivary glands.
The excretory system is the Malpighian vessels that empty into the posterior intestine.
Respiratory organs - trachea.
The circulatory system is poorly developed, not closed. Blood - hemolymph - does not carry formed elements, but performs only a trophic function.
The development of insects occurs with metamorphosis. In some, the metamorphosis is complete, with the replacement of larval organs by imago organs at the pupal stage; in others, it is incomplete (the larva looks like an adult, and the pupal stage is absent).
Epidemiological classification
I Domestic insects
Temporary.
Detachment Bed bugs heliptera
Bed bug Cimex lectularius - it is known that pathogens of many vector-borne diseases can remain viable in the body of bugs for a long time: rickettsia typhus and relapsing spirochetes, visceral leishmaniasis and plague. However, there is no evidence for the role of bed bugs in the transmission of these infections.
Order Flea Aphaniptera
Human flea Pulex irritans - a carrier of plague pathogens
Permanent.
Order Lice Anoplura
Clothes louse Pediculus vestimenti - carries pathogens of relapsing and typhus
Pubic louse Phthirus pubis - causes pediculosis
2.Mechanical carriers
Order Cockroaches Blattoidea
Black cockroach Blatta orientales
Red cockroach Blattella germanica - carry pathogens of GI infections, viruses, bacteria, diphtheria, protozoan cysts, helminth eggs, etc.
The Musca domestica housefly is more dangerous than cockroaches, like fur. carrier,
II Pathogens
Wolfart fly Wohlfahrtia magnifica - larvae cause myiasis in mammals, mainly in sheep, but also in cattle, goats, horses and rarely in humans.
Order Diptera Diptera
Family Mosquitoes Culicidae - carry pathogens of encephalitis and tularemia, malaria
Mosquito family Phlebotomidae - carry different types of leishmania, pappatachi fever viruses
The horsefly family Tabanidae - in the northern latitudes are carriers of anthrax and tularemia pathogens, and in the tropics - loiasis pathogens.
The Simuliidae family of midges - carry pathogens of onchocerciasis
The Ceratopogonidae family of biting midges carry pathogens of some filariasis.