**3. Diversity among Diptera**

The close association of dipteran flies with humans has led them to be recognized as unpleasant and disturbing creatures, and certainly some flies are responsible for millions of illnesses and deaths among human populations. Yet flies are also among the key components in most ecosystems and known advantageous in many ways. Voluminous flies are of great economic importance because some bloodsuckers are serious pests of humans and other animals. These insects are key vectors of some diseases, although others are pests of cultivated plants. Flies are advantageous as well by operating as predators or parasites of certain insects, scavengers as well as pollinators of plants and killers of weeds harmful to persons. Often called maggots or grubs, dipterous larvae, are found in many habitats (in water, plant tissue and soil, animal matter and decaying plants, below stones or bark, pools of crude petroleum), whereas adults forage on plant or animal juices or other insects. Diptera falls into three big sets, Nematocera (flies with multi-segmented antennae such as crane flies, midges, gnats, mosquitoes), Brachycera (flies with stylate antennae, for instance, horse flies, robber flies, bee flies) and Cyclorrhapha (flies with aristate antennae, such like, flies that breed in vegetable or animal material,

Dipteran insects are plentiful all over the sphere, in the tropics and subarctic, at oceanic level and on elevated peaks. These inhabit seashores to low-tide level, however, a small number move into deeper water and merely one or two midges are actually oceanic (*Pontomyia natans* Edwards in the Pacific). In contrast, wandering flies have been observed at much distant to marine. In general, flies vary in dimensions from robber flies more than 7 cm lengthy to midges of little more than 1 mm long. As a whole, the more-primitive flies (midges, mosquitoes, fungus gnats) are fragile insects and with delicate wings. The more-progressive flies (house flies, blow flies) are commonly bristly, thick and tough, and forceful fliers than gnats and

Even though these have simply two wings, flies are among the greatest aerialists in the world of insects as they can fly forwards and backwards, turn at any place, hover, and even fly upside and down to land on a top boundary. Flies have the uppermost wing-beat rate than any of other animal. It may be as high as 1000 beats per second in case of some small midges. Generally, through the wing-beat frequency of a virgin female, male mosquitoes are attracted. Maggots of certain shore flies (family Ephydridae) live in uncommon habitations, which would destroy other insects. For instance, *Ephydra brucei* survives in warm geysers and springs wherever the water hotness go beyond 112°F. The petroleum fly *Helaeomyia petrolei* Coquillett

both living and dead) [2, 3].

*Life Cycle and Development of Diptera*

**2. General features**

midges.

**Figure 1.** *Wetland ecosystem.*

**2**

Diptera have successfully colonized all continents including Antarctica, and are diverse not only in species richness, but also in their structure, habitat exploitation, life habits and interactions with humankind [5].

Maximum of nourishing and buildup of biomass take place in the larval stages and adults Diptera generally take energy they require to supply their flight muscles. Among those flies that forage widely, their foods contain honeydew or nectar (Blephariceridae and Bombyliidae), vertebrate blood (Culicidae and Glossinidae), pollen (Nemestrinidae and Syrphidae), insect hemolymph (certain Ceratopogonidae) and other biological resources that are liquefied or can be suspended or dissolved in regurgitated fluid or saliva (Muscidae, Calliphoridae and Micropezidae). The grownups of several groups are predaceous (Asilidae, Empididae and some Scathophagidae), while those of a few Diptera (Oestridae and Deuterophlebiidae) that totally lack of mouthparts, do not take food and live only for a short period [6].

Larvae of most species can be considered aquatic for existence, they need moist to wet atmosphere inside living tissues of plants, within decaying organic matters, as parasitoids or parasites of animals, or else are in link with water bodies. Maximum of larvae are free-living and crawl, tunnel or swim vigorously in water (Culicidae, Chironomidae, Chaoboridae, Simuliidae), sediments (Tabanidae, Tipulidae, Ceratopogonidae, Psychodidae), wood (Axymyiidae, Tipulidae, some Syrphidae), fruits (Tephritidae, Chloropidae), or decomposing biological material (Muscidae, Ephydridae, Sphaeroceridae, Sarcophagidae), whereas other larvae dwell in the tissues of alive creatures (Oestridae, Acroceridae, Tachinidae, Pipunculidae) [7].

### **4. Prominence of Diptera**

The utmost essential significance of flies is not based only on limited acquainted families that comprise mosquitoes, tsetse flies, houseflies and other annoyance insects, but rather in the huge numbers of unfamiliar species that are a vital component in food chains upon which much of life rests on. Flies are of considerable ecological importance and their abundance, worldwide distribution and habits combine to make them a nuisance to humans by landing on people or entering homes or businesses. Midges and gnats are common names for a large number of small, non-biting flies and an important part of aquatic food chains. Swarms or clouds of midges in the air are a collective nuisance. Face flies and sweat flies, gather nearby the mouth, eyes and nose, and likewise suck pus and blood from sores and wounds. Such flies constantly move from one individual to the subsequent and in doing so, sometimes can transmit disease-causing pathogens [8].

vertebrates or else whether it has a human parasite that became adapted to live in a

Malaria is a cyclically transmitted significant disease and causal mediator of human malaria, *Plasmodium*, is a cellular protist that feeds in human blood on red blood cells. Its propagative cycles cause repeated attacks of illness. Sometimes sexual forms take place in blood of victims. When this form catches its mode into an appropriate blood sucking mosquito, a different phase of *Plasmodium* arises, making an organism to contaminate one more human host bitten by mosquito species. Further illnesses recognized to be transmitted cyclically comprise encepha-

Some flies larvae are severe pests of agriculture, they forage on young and mature crop plants and check growth otherwise destroy them. Cultured crops, for the reason that they offer to pests with a nearly limitless nutrition resource inside a small space, may be destroyed by uncontrolled density of a pest. In contrast, wild food plants, for the reason that they are mixed and scattered with other varieties, do not generally offer much plentiful of food supply and therefore work as a check on population growth. Fruit flies may result a 20% damage of an oat crop and to the value of the lost oats might be added the price of control actions essential to protect the leftovers. Several crops, particularly ornamental shrubs and fruit trees are of an economic injury if to some extent spoiled by insect invasion, although the life of plant is not threatened. Fruit, although is eatable afterward injured by Mediterranean fruit flies, yet cannot be traded since a limited infected fruits can result in loss of an entire consignment. Larvae of leaf miners and gall midges reduce the saleable

Brown white-tipped brown bee fly *Comptosia walkeri* Edwards (brown in color with golden hairs on body and wings having white stripe on tips) (**Figure 2**) and fly *Comptosia insignis* (Walker) are members of family Bombyliidae. These flies superficially resemble to bees owing to their bodies built stoutly that are shielded with hair and by bearing their long and thin proboscis. These together with their flight lifestyles have gotten them collective name of bee flies or humble flies. Adults may be seen frequently hovering over or resting on blossoms or areas of plain ground in sunlit localities. Adults of bee flies suckle on nectar from a widespread diversity of floras and can be key pollinators of plants. Even though a slight is recognized about

litis, filariasis, yellow fever and other viral infections [12].

*Typical Flies: Natural History, Lifestyle and Diversity of Diptera*

*DOI: http://dx.doi.org/10.5772/intechopen.91391*

price of ornamental plants [8, 13, 14].

**Figure 2.** *Comptosia walkeri.*

**5**

biting fly [11].

The order of true flies contains more species with aquatic stages than any other insect group. Unlike all other invertebrate orders, dipterans contain many species that as adults are harmful or at least annoying to humans. At the top of the list are mosquitoes; however other harmful groups comprise horse flies, black flies, deer flies and biting midges. Various fully-grown dipterans transfer pathogens or parasitic diseases that can be fatal or devastating to persons, such as dengue, malaria, yellow fever, and West Nile virus. Furthermore, other flies (some midges) develop in such great numbers that they may cause allergic responses in persons or else block air conditioning items. Conversely, dipteran larvae are tremendously essential in aquatic food webs and specific groups are raised in hatcheries as fish diet, and several fully-grown dipterans are a vital food for dragonflies and birds such as swifts, swallows, flycatchers and phoebes [9].

In warm countries, eye gnats are an annoyance and although their larvae are plant feeders, the tiny active adults forage on physiological secretions, generally those around the eyes. Additionally, few flies cut the skin of vertebrates and nourish on their blood. Sand flies, mosquitoes, black flies, horse flies and biting midges have developed maxillae and blade like mandibles with piercing stylets. Such piercing organs are evolved only in females, which for egg production usage blood protein, whereas male dos not forage on blood [10].

Other flies groups have developed diverse devices for attaining blood meal. Stable flies, tsetse flies or biting house flies (*Stomoxys*), and some parasitic flies have evolved a tough drill like labium to substitute the soft sponge like mouth part. Both females and males have developed this labium and they forage on blood. A small number of flies correlated to the house fly have a spongy proboscis furnished with minor teeth for scratchy skin around sores and wounds to raise lymph and blood flow. Other insects (robber flies) have evolved piercing proboscis merely used against other insects.

Spread of disease that takes place by use of piercing organs such as a proboscis is reflected as mechanical transmission. In the blood, disease-producing organisms might be picked up by a fly introducing its proboscis into an infested individual. Then disease can be transferred by blood sucking fly, which injects its saliva into the wound of other persons when their skin is pierced. Without anticoagulant properties of saliva, blood sucking would be difficult as the minute hole drilled by proboscis would block with coagulated blood. When mouthparts are contaminated with blood that contains microorganisms, they can be injected together with saliva, into another person; this is termed as direct transmission of disease. One contagious disease caused by a bacterium found in wild rodents is tularemia that may be transferred in this way. Trappers who cut themselves while skinning animals can contract with the disease. The bacterium is also transmitted by deer fly (*Chrysops discalis*), Williston common in wooded trapper country.

In the Middle East and parts of Asia, surra is a disease of horses and camels caused by the protozoan *Trypanosoma evansi* and transmitted by horse flies. Trypanosomes are transferred by tsetse flies that cause sleeping sickness in humans and nagana in animals all over tropical Africa. These trypanosomes essentially pass a portion of their life cycle in the insect prior to they can contaminate a vertebrate host and this is an example of cyclic disease communication. The connection between two hosts, vertebrate and insect and parasitic disease organism is a result of evolutionary adaptation. On the other hand, it is not recognized whether the trypanosome originally has a fly parasite that speeded to humans and other

#### *Typical Flies: Natural History, Lifestyle and Diversity of Diptera DOI: http://dx.doi.org/10.5772/intechopen.91391*

nearby the mouth, eyes and nose, and likewise suck pus and blood from sores and wounds. Such flies constantly move from one individual to the subsequent and in

The order of true flies contains more species with aquatic stages than any other insect group. Unlike all other invertebrate orders, dipterans contain many species that as adults are harmful or at least annoying to humans. At the top of the list are mosquitoes; however other harmful groups comprise horse flies, black flies, deer flies and biting midges. Various fully-grown dipterans transfer pathogens or parasitic diseases that can be fatal or devastating to persons, such as dengue, malaria, yellow fever, and West Nile virus. Furthermore, other flies (some midges) develop in such great numbers that they may cause allergic responses in persons or else block air conditioning items. Conversely, dipteran larvae are tremendously essential in aquatic food webs and specific groups are raised in hatcheries as fish diet, and several fully-grown dipterans are a vital food for dragonflies and birds such as

In warm countries, eye gnats are an annoyance and although their larvae are plant feeders, the tiny active adults forage on physiological secretions, generally those around the eyes. Additionally, few flies cut the skin of vertebrates and nourish on their blood. Sand flies, mosquitoes, black flies, horse flies and biting midges have developed maxillae and blade like mandibles with piercing stylets. Such piercing organs are evolved only in females, which for egg production usage blood protein,

Other flies groups have developed diverse devices for attaining blood meal. Stable flies, tsetse flies or biting house flies (*Stomoxys*), and some parasitic flies have evolved a tough drill like labium to substitute the soft sponge like mouth part. Both females and males have developed this labium and they forage on blood. A small number of flies correlated to the house fly have a spongy proboscis furnished with minor teeth for scratchy skin around sores and wounds to raise lymph and blood flow. Other insects (robber flies) have evolved piercing proboscis merely used

Spread of disease that takes place by use of piercing organs such as a proboscis is reflected as mechanical transmission. In the blood, disease-producing organisms might be picked up by a fly introducing its proboscis into an infested individual. Then disease can be transferred by blood sucking fly, which injects its saliva into the wound of other persons when their skin is pierced. Without anticoagulant properties of saliva, blood sucking would be difficult as the minute hole drilled by proboscis would block with coagulated blood. When mouthparts are contaminated with blood that contains microorganisms, they can be injected together with saliva, into another person; this is termed as direct transmission of disease. One contagious disease caused by a bacterium found in wild rodents is tularemia that may be transferred in this way. Trappers who cut themselves while skinning animals can contract with the disease. The bacterium is also transmitted by deer fly (*Chrysops*

In the Middle East and parts of Asia, surra is a disease of horses and camels caused by the protozoan *Trypanosoma evansi* and transmitted by horse flies. Trypanosomes are transferred by tsetse flies that cause sleeping sickness in humans and nagana in animals all over tropical Africa. These trypanosomes essentially pass a portion of their life cycle in the insect prior to they can contaminate a vertebrate host and this is an example of cyclic disease communication. The connection between two hosts, vertebrate and insect and parasitic disease organism is a result of evolutionary adaptation. On the other hand, it is not recognized whether the trypanosome originally has a fly parasite that speeded to humans and other

doing so, sometimes can transmit disease-causing pathogens [8].

swifts, swallows, flycatchers and phoebes [9].

*Life Cycle and Development of Diptera*

whereas male dos not forage on blood [10].

*discalis*), Williston common in wooded trapper country.

against other insects.

**4**

vertebrates or else whether it has a human parasite that became adapted to live in a biting fly [11].

Malaria is a cyclically transmitted significant disease and causal mediator of human malaria, *Plasmodium*, is a cellular protist that feeds in human blood on red blood cells. Its propagative cycles cause repeated attacks of illness. Sometimes sexual forms take place in blood of victims. When this form catches its mode into an appropriate blood sucking mosquito, a different phase of *Plasmodium* arises, making an organism to contaminate one more human host bitten by mosquito species. Further illnesses recognized to be transmitted cyclically comprise encephalitis, filariasis, yellow fever and other viral infections [12].

Some flies larvae are severe pests of agriculture, they forage on young and mature crop plants and check growth otherwise destroy them. Cultured crops, for the reason that they offer to pests with a nearly limitless nutrition resource inside a small space, may be destroyed by uncontrolled density of a pest. In contrast, wild food plants, for the reason that they are mixed and scattered with other varieties, do not generally offer much plentiful of food supply and therefore work as a check on population growth. Fruit flies may result a 20% damage of an oat crop and to the value of the lost oats might be added the price of control actions essential to protect the leftovers. Several crops, particularly ornamental shrubs and fruit trees are of an economic injury if to some extent spoiled by insect invasion, although the life of plant is not threatened. Fruit, although is eatable afterward injured by Mediterranean fruit flies, yet cannot be traded since a limited infected fruits can result in loss of an entire consignment. Larvae of leaf miners and gall midges reduce the saleable price of ornamental plants [8, 13, 14].

Brown white-tipped brown bee fly *Comptosia walkeri* Edwards (brown in color with golden hairs on body and wings having white stripe on tips) (**Figure 2**) and fly *Comptosia insignis* (Walker) are members of family Bombyliidae. These flies superficially resemble to bees owing to their bodies built stoutly that are shielded with hair and by bearing their long and thin proboscis. These together with their flight lifestyles have gotten them collective name of bee flies or humble flies. Adults may be seen frequently hovering over or resting on blossoms or areas of plain ground in sunlit localities. Adults of bee flies suckle on nectar from a widespread diversity of floras and can be key pollinators of plants. Even though a slight is recognized about

**Figure 2.** *Comptosia walkeri.*

some species, bee flies larvae are thought to parasitize the larvae of other insects and may prey on egg-masses of locusts and grasshoppers [15].

The house fly (*Musca domestica* Linnaeus) (**Figure 4**) can be dangerous because it moves from person to food, drinks, garbage, carrion or feces. It is possibly our most public adult fly and though this is a non-biting fly, it may be of significant prominence as a nuisance. In addition, it has a probable role for mechanical transmission of several sickness causing agents owing to its occurrence in fecal and decomposing organic matters. Through transferring of infective organisms from decomposing material or from infected people, house flies are agents in transmitting of typhoid, dysentery, cholera, summer diarrhea in children, and other intesti-

The house fly is about 6–7 mm in length and females generally bigger than the males. The female may be differentiated from the male by means of comparatively broader space among the eyes (in males eyes mostly touch). The head of adult fly has reddish eyes; thorax bears four narrow black stripes, while abdomen is gray or yellowish with dark midline and irregular dark markings on the sides. The mouth parts of this fly are modified for lapping up of food material. The egg is about 1.2 mm in length, white colored and singly laid; however, eggs are stacked in small clusters. Every female fly may deposit up to 500 eggs in a number of groups containing 75–150 eggs in a period of 3–4 days. The legless maggot emerges from the egg in warm weather within eight to 20 hours. Early instars larvae are 3–9 mm long, typical creamy whitish in color, cylindrical, but tapering toward the head. The larva goes through three instars; a full-grown maggot is 7–12 mm long and has a greasy, cream-colored appearance. The pupal stage, about 8 mm long, is passed in a pupal case formed from the last larval skin which varies in color from yellow, red, brown, to black as the pupa ages. Pupae at 32–37°C, acquire their complete development in 2–6 days, but at about 14°C need 17–27 days. The evolving fly discharges from pupal case by the usage of a consecutively shrinking and swelling sac known as

Generally, warm season situations are ideal for the development of house fly and in as little as 7–10 days, it can complete its life cycle. On the other hand, the

Face fly *Musca autumnalis* DeGeer is a serious pest of cattle though this is a non-

Any member of the order Diptera has evolved a simplified structure and physiological diversity. Dipteran larvae can be differentiated from maximum of other insects by means of their absence of segmented thoracic legs. As a replacement for the customary jointed legs, several crowds have one or more couples of fleshy locomotory prolegs on abdomen and or thorax, each with curled or even hook-like spines. Fleshy tubercles arise in several species and help together in locomotory and sensory tasks. The larva head may be heavily sclerotized and exposed, as in midges, or else toughly condensed and only moderately proud (from time to time only with mouthparts expanded). The abdomen and thorax are generally fleshy, from time to time with dispersed sclerotized plates, and the whole body is usually long and

whereas in subtropical and tropical regions more than 20 generations can take

biting fly. Adults come together in great numbers around the face of cattle and other big ungulates. This has been involved in the spread of 'pink-eye' between cattle and its occurrence in great numbers has been liable for indirect harms in production comprising reduced weight gains and milk production. The adults are at

life cycle may require up to 2 months under suboptimal conditions. In temperate regions, as many as 10–12 generations may occur annually,

nal virus and bacteria causing diseases.

*DOI: http://dx.doi.org/10.5772/intechopen.91391*

*Typical Flies: Natural History, Lifestyle and Diversity of Diptera*

ptilinum, to breakdown through the case.

maximum vigorous from spring through fall.

**5. Anatomy and physiology**

place [39].

**7**

Family Tephritidae comprises peach fruit fly *Bactrocera zonata* (Saunders) mainly pest on peach and other stone fruits; guava fruit fly *Bactrocera correcta* (Bezzi) common on guava, mango and citrus; oriental fruit fly *Bactrocera dorsalis* Hendel recorded on fruits and vegetables; and melon fly *Bactrocera cucurbitae* (Coquillett) that is a major nuisance of cucurbitaceous vegetables (**Figure 3**) [16–19]. Overall, the damage to fruits and vegetables caused by fruit flies results from adults oviposition in hosts and soft tissues of vegetative parts of certain plants, feeding by white legless maggots, and decomposition of hosts tissue by invading secondary microorganisms [20–23]. Integrated pest management (IPM) packages for fruit flies include, mechanical controlling by protective coverings on the host and the destruction of adults with baiting and male annihilation techniques, biological control with biopesticides and parasitoids, cultural control through field sanitation and resistant varieties, using selective pesticides for backup only, and post-harvest control by careful host selection and hot water immersion treatment [24–38].

**Figure 4.** Musca domestica*.*

#### *Typical Flies: Natural History, Lifestyle and Diversity of Diptera DOI: http://dx.doi.org/10.5772/intechopen.91391*

some species, bee flies larvae are thought to parasitize the larvae of other insects

Family Tephritidae comprises peach fruit fly *Bactrocera zonata* (Saunders) mainly pest on peach and other stone fruits; guava fruit fly *Bactrocera correcta* (Bezzi) common on guava, mango and citrus; oriental fruit fly *Bactrocera dorsalis* Hendel recorded on fruits and vegetables; and melon fly *Bactrocera cucurbitae* (Coquillett) that is a major nuisance of cucurbitaceous vegetables (**Figure 3**) [16–19]. Overall, the damage to fruits and vegetables caused by fruit flies results from adults oviposition in hosts and soft tissues of vegetative parts of certain plants, feeding by white legless maggots, and decomposition of hosts tissue by invading secondary microorganisms [20–23]. Integrated pest management (IPM) packages for fruit flies include, mechanical controlling by protective coverings on the host and the destruction of adults with baiting and male annihilation techniques, biological control with biopesticides and parasitoids, cultural control through field sanitation and resistant varieties, using selective pesticides for backup only, and post-harvest control by careful host selection and hot water immersion

*(a)* Bactrocera zonata, *(b)* Bactrocera dorsalis*, (c)* Bactrocera correcta*, (d)* Bactrocera cucurbitae*.*

and may prey on egg-masses of locusts and grasshoppers [15].

*Life Cycle and Development of Diptera*

treatment [24–38].

**Figure 3.**

**Figure 4.** Musca domestica*.*

**6**

The house fly (*Musca domestica* Linnaeus) (**Figure 4**) can be dangerous because it moves from person to food, drinks, garbage, carrion or feces. It is possibly our most public adult fly and though this is a non-biting fly, it may be of significant prominence as a nuisance. In addition, it has a probable role for mechanical transmission of several sickness causing agents owing to its occurrence in fecal and decomposing organic matters. Through transferring of infective organisms from decomposing material or from infected people, house flies are agents in transmitting of typhoid, dysentery, cholera, summer diarrhea in children, and other intestinal virus and bacteria causing diseases.

The house fly is about 6–7 mm in length and females generally bigger than the males. The female may be differentiated from the male by means of comparatively broader space among the eyes (in males eyes mostly touch). The head of adult fly has reddish eyes; thorax bears four narrow black stripes, while abdomen is gray or yellowish with dark midline and irregular dark markings on the sides. The mouth parts of this fly are modified for lapping up of food material. The egg is about 1.2 mm in length, white colored and singly laid; however, eggs are stacked in small clusters. Every female fly may deposit up to 500 eggs in a number of groups containing 75–150 eggs in a period of 3–4 days. The legless maggot emerges from the egg in warm weather within eight to 20 hours. Early instars larvae are 3–9 mm long, typical creamy whitish in color, cylindrical, but tapering toward the head. The larva goes through three instars; a full-grown maggot is 7–12 mm long and has a greasy, cream-colored appearance. The pupal stage, about 8 mm long, is passed in a pupal case formed from the last larval skin which varies in color from yellow, red, brown, to black as the pupa ages. Pupae at 32–37°C, acquire their complete development in 2–6 days, but at about 14°C need 17–27 days. The evolving fly discharges from pupal case by the usage of a consecutively shrinking and swelling sac known as ptilinum, to breakdown through the case.

Generally, warm season situations are ideal for the development of house fly and in as little as 7–10 days, it can complete its life cycle. On the other hand, the life cycle may require up to 2 months under suboptimal conditions. In temperate regions, as many as 10–12 generations may occur annually, whereas in subtropical and tropical regions more than 20 generations can take place [39].

Face fly *Musca autumnalis* DeGeer is a serious pest of cattle though this is a nonbiting fly. Adults come together in great numbers around the face of cattle and other big ungulates. This has been involved in the spread of 'pink-eye' between cattle and its occurrence in great numbers has been liable for indirect harms in production comprising reduced weight gains and milk production. The adults are at maximum vigorous from spring through fall.
