-
August
-
Five Star Movement
-
Washington Post
-
Edward Snowden
-
Language acquisition
-
British humour
-
Al Bano and Romina Power
-
Vladimir Putin
-
Artificial Intelligence
-
Artists and repertoire
-
Table tennis
-
List of Wikipedia controversies
-
Joke
-
Prince George of Cambridge
-
Giuseppe Ungaretti
-
International English
-
Mosquito
-
Flying saucer
-
Breakfast cereal
-
Bingo (UK)
-
Multilingualism
-
Religion in ancient Rome
-
Giallo
-
The Shock Doctrine
-
PDF (Portable Document Format)
-
Nazi plunder
-
Nanotechnology
-
Jennifer Lopez
-
Decline of Detroit
-
Firefox OS
-
Burj Khalifa (tallest building in the world)
|
WIKIMAG n. 9 - Agosto 2013
Mosquito
Text is available under the
Creative Commons Attribution-ShareAlike License; additional
terms may apply. See
Terms of
Use for details.
Wikipedia® is a registered trademark of the
Wikimedia Foundation,
Inc., a non-profit organization.
Traduzione
interattiva on/off
- Togli il segno di spunta per disattivarla
The mosquitoes are a
family of small,
midge-like
flies: the
Culicidae. Although a few species are harmless or even useful to
humanity, most are a nuisance because they consume blood from living
vertebrates, including
humans.
The females of many species of mosquitoes are
blood-eating pests. In feeding on blood, some of them transmit
extremely harmful human and
livestock diseases, such as
malaria,
yellow fever and
filariasis. Some authorities argue accordingly that mosquitoes are
the most dangerous animals on Earth.[2]
Introduction
Mosquitoes are members of a
family of
nematocerid
flies: the Culicidae (from the
Latin
culex,
genitive culicis meaning "midge" or "gnat").[3]
The word "mosquito" (formed by mosca and
diminutive ito) is from the
Spanish or
Portuguese for "little
fly".[4]
Superficially, mosquitoes resemble
crane
flies (family
Tipulidae) and chironomid flies (family
Chironomidae); as a result, casual observers seldom realize the
important differences between the members of the respective families. In
particular, the females of many species of mosquitoes are blood-eating
pests and dangerous
vectors of diseases, whereas members of the similar-looking
Chironomidae and Tipulidae are not. Many species of mosquitoes are not
blood eaters, and many of those that do create a "high to low pressure"
in the blood to obtain it do not transmit disease. Also, in the
bloodsucking species, only the females suck blood. Furthermore, even
among mosquitoes that do carry important diseases, neither all species
of mosquitoes, nor all strains of a given species transmit the same
kinds of diseases, nor do they all transmit the diseases under the same
circumstances; their habits differ. For example, some species attack
people in houses, and others prefer to attack people walking in forests.
Accordingly, in managing public health, knowing which species, even
which strains, of mosquitoes with which one is dealing is important.
Over 3,500 species of mosquitoes have already been
described from various parts of the world.[5][6]
Some mosquitoes that bite humans routinely act as
vectors for a number of infectious diseases affecting millions of
people per year.[7][8]
Others that do not routinely bite humans, but are the vectors for animal
diseases, may become disastrous agents for
zoonosis of new diseases when their habitats are disturbed, for
instance by sudden deforestation.[9][10]
Many scientists have suggested that complete
eradication of mosquitoes would not have serious ecological
consequences.[11][12]
Life cycle
Anopheles larva from southern Germany, about 8 mm
long
Image of pitcher plant mosquito
Wyeomyia smithii, showing segmentation and partial
anatomy of circulatory system
Like all flies, mosquitoes go through four stages in their
lifecycles:
egg,
larva, pupa,
and adult or
imago. In most species, adult females lay their eggs in stagnant
water; some lay eggs near the water's edge; others attach their eggs to
aquatic plants. Each species selects the situation of the water into
which it lays its eggs and does so according to its own ecological
adaptations. Some are generalists and are not very fussy. Some breed in
lakes, some in temporary puddles. Some breed in marshes, some in
salt-marshes. Among those that breed in salt water, some are equally at
home in fresh and salt water up to about one-third the concentration of
seawater, whereas others must acclimatize themselves to the salinity.[13]
Such differences are important because certain ecological preferences
keep mosquitoes away from most humans, whereas other preferences bring
them right into houses at night.
Some species of mosquitoes prefer to breed in
phytotelmata (natural reservoirs on plants), such as rainwater
accumulated in holes in tree trunks, or in the leaf-axils of
bromeliads. Some specialize in the liquid in pitchers of particular
species of
pitcher plants, their larvae feeding on decaying insects that had
drowned there or on the associated bacteria; the genus Wyeomyia
provides such examples — the harmless Wyeomyia smithii breeds
only in the pitchers of
Sarracenia purpurea.[14]
However, some species of mosquitoes that are adapted to breeding in
phytotelmata are dangerous disease vectors. In nature, they might occupy
anything from a hollow tree trunk to a cupped leaf. Such species
typically take readily to breeding in artificial water containers, such
as the odd plastic bucket, flowerpot "saucer", or discarded bottle or
tire. Such casual puddles are important breeding places for some of the
most serious disease vectors, such as species of
Aedes
that transmit dengue and yellow fever. Some with such breeding habits
are disproportionately important vectors because they are well-placed to
pick up
pathogens from humans and pass them on. In contrast, no matter how
voracious, mosquitoes that breed and feed mainly in remote wetlands and
salt marshes may well remain uninfected, and if they do happen to become
infected with a relevant pathogen, might seldom encounter humans to
infect, in turn.
The first three stages—egg, larva, and pupa—are largely aquatic.
These stages typically last five to 14 days, depending on the species
and the ambient temperature, but there are important exceptions.
Mosquitoes living in regions where some seasons are freezing or
waterless spend part of the year in
diapause; they delay their development, typically for months, and
carry on with life only when there is enough water or warmth for their
needs. For instance, Wyeomyia larvae typically get frozen into
solid lumps of ice during winter and only complete their development in
spring. The eggs of some species of Aedes remain unharmed in
diapause if they dry out, and hatch later when they are covered by
water.
Eggs hatch to become
larvae,
which grow until they are able to change into
pupae. The
adult mosquito emerges from the mature pupa as it floats at the water
surface. Bloodsucking mosquitoes, depending on species, gender, and
weather conditions, have potential adult lifespans ranging from as short
as a week to as long as several months.
Some species can overwinter as adults in diapause.[15][16]
Eggs and
oviposition
An egg raft of a Culex species, partly broken,
showing individual egg shapes
Mosquito habits of
oviposition, the ways in which they lay their eggs, vary
considerably between species, and the
morphologies of the eggs vary accordingly. The simplest procedure is
that followed by many species of
Anopheles; like many other
gracile species of aquatic insects, females just fly over the water,
bobbing up and down to the water surface and dropping eggs more or less
singly. The bobbing behavior occurs among some other aquatic insects, as
well, for example
mayflies and
dragonflies; it sometimes is called "dapping".
The eggs of Anopheles species are roughly cigar-shaped and have
floats down their sides. Females of many common species can lay 100–200
eggs during the course of the adult phase of their lifecycles. Even with
high egg and intergenerational mortality, over a period of several
weeks, a single successful breeding pair can create a population of
thousands.
Some other species, for example members of the genus
Mansonia, lay their eggs in arrays, attached usually to the
under-surfaces of waterlily pads. Their close relatives, the genus
Coquillettidia, lay their eggs similarly, but not attached to
plants. Instead, the eggs form layers called "rafts" that float on the
water. This is a common mode of oviposition, and most species of
Culex are known for the habit, which also occurs in some other
genera, such as
Culiseta and
Uranotaenia. Anopheles eggs may on occasion cluster
together on the water, too, but the clusters do not generally look much
like compactly glued rafts of eggs.
In species that lay their eggs in rafts, rafts do not form
adventitiously; the female Culex settles carefully on still water
with her hind legs crossed, and as she lays the eggs one by one, she
twitches to arrange them into a head-down array that sticks together to
form the raft.[17]
Aedes females generally drop their eggs singly, much as
Anopheles do, but not as a rule into water. Instead, they lay their
eggs on damp mud or other surfaces near the water's edge. Such an
oviposition site commonly is the wall of a cavity such as a hollow stump
or a container such as a bucket or a discarded vehicle tire. The eggs
generally do not hatch until they are flooded, and they may have to
withstand considerable desiccation before that happens. They are not
resistant to desiccation straight after oviposition, but must develop to
a suitable degree first. Once they have achieved that, however, they can
enter diapause for several months if they dry out. Clutches of eggs of
the majority of mosquito species hatch as soon as possible, and all the
eggs in the clutch hatch at much the same time. In contrast, a batch of
Aedes eggs in diapause tends to hatch irregularly over an
extended period of time. This makes it much more difficult to control
such species than those mosquitoes whose larvae can be killed all
together as they hatch. Some Anopheles species do also behave in
such a manner, though not to the same degree of sophistication.[18]
Larva
Mosquito larvae and pupa resting at water surface
The mosquito larva has a well-developed head with mouth brushes used
for feeding, a large
thorax with no legs, and a segmented
abdomen.
Larvae breathe through
spiracles located on their eighth abdominal segments, or through a
siphon, so must come to the surface frequently. The larvae spend most of
their time feeding on
algae,
bacteria, and other microbes in the surface
microlayer. They dive below the surface only when disturbed. Larvae
swim either through
propulsion with their mouth brushes, or by jerky movements of their
entire bodies, giving them the common name of "wigglers" or "wrigglers".
Larvae develop through four stages, or
instars,
after which they
metamorphose into
pupae. At the end of each instar, the larvae molt, shedding their
skins to allow for further growth.
Pupa
Culex larvae plus one pupa
Anatomy of an adult mosquito
As seen in its
lateral aspect, the mosquito pupa is comma-shaped. The head and
thorax are merged into a
cephalothorax, with the abdomen curving around underneath. The pupa
can swim actively by flipping its abdomen, and it is commonly called a
"tumbler" because of its swimming action. As with the larvae, the pupae
of most species must come to the surface frequently to breathe, which
they do through a pair of respiratory trumpets on their cephalothoraces.
However, pupae do not feed during this stage; typically they pass their
time hanging from the surface of the water by their respiratory
trumpets. If alarmed, say by a passing shadow, they nimbly swim
downwards by flipping their abdomens in much the same way as the larvae
do. If undisturbed, they soon float up again. After a few days or
longer, depending on the temperature and other circumstances, the pupa
rises to the water surface, the
dorsal surface of its cephalothorax splits, and the adult mosquito
emerges. The lower activity of the pupa compared to the larva is
understandable, bearing in mind that it does not feed, whereas the larva
feeds constantly.[17]
Adult
Adults of the yellow fever mosquito
Aedes aegypti, a typical member of the subfamily
Culicinae, the male is on the left, and females are on
the right. Note the bushy antennae and longer
palps in the male.
The period of development from egg to adult varies among species and
is strongly influenced by ambient temperature. Some species of
mosquitoes can develop from egg to adult in as few as five days, but a
more typical period of development in tropical conditions would be some
40 days or more for most species. The variation of the body size in
adult mosquitoes depends on the density of the larval population and
food supply within the breeding water.
Adult mosquitoes usually mate within a few days after emerging from
the pupal stage. In most species, the males form large
swarms, usually around dusk, and the females fly into the swarms to
mate.
Males typically live for about a week, feeding on
nectar
and other sources of
sugar.
After obtaining a full blood meal, the female will rest for a few days
while the blood is digested and eggs are developed. This process depends
on the temperature, but usually takes two to three days in tropical
conditions. Once the eggs are fully developed, the female lays them and
resumes host-seeking.
The cycle repeats itself until the female dies. While females can
live longer than a month in captivity, most do not live longer than one
to two weeks in nature. Their lifespans depend on temperature, humidity,
and their ability to successfully obtain a blood meal while avoiding
host defenses and predators.
Length of the adult varies, but is rarely greater than 16 mm
(0.6 in),[19]
and weight up to 2.5 milligrams (0.04 grains).
All mosquitoes have slender bodies with three segments: head, thorax and
abdomen.
The head
is specialized for receiving sensory information and for feeding. It has
eyes and a pair of long, many-segmented
antennae. The antennae are important for detecting host odors, as
well as odors of breeding sites where females lay eggs. In all mosquito
species, the antennae of the males in comparison to the females are
noticeably bushier and contain auditory receptors to detect the
characteristic whine of the females. The
compound eyes are distinctly separated from one another. Their
larvae only possess a pit-eye ocellus. The compound eyes of adults
develop in a separate region of the head.[20]
New ommatidia are added in semicircular rows at the rear of the eye.
During the first phase of growth, this leads to individual ommatidia
being square, but later in development they become hexagonal. The
hexagonal pattern will only become visible when the carapace of the
stage with square eyes is molted.[20]
The head also has an elongated, forward-projecting, "stinger-like"
proboscis used for feeding, and two sensory palps. The maxillary
palps of the males are longer than their proboscises, whereas the
females’ maxillary palps are much shorter. In typical bloodsucking
species, the female has an elongated proboscis.
The thorax is specialized for locomotion. Three pairs of legs and a
pair of wings are attached to the thorax. The
insect wing is an outgrowth of the exoskeleton. The Anopheles
mosquito can fly for up to four hours continuously at 1–2 km/h
(0.6–1 mph),[21]
traveling up to 12 km (7.5 mi) in a night. Males beat their wings
between 450 and 600 times per second.[22]
The abdomen is specialized for food digestion and egg development;
the abdomen of a mosquito can hold three times its own weight in blood.[23]
This segment expands considerably when a female takes a blood meal. The
blood is digested over time, serving as a source of
protein
for the production of eggs, which gradually fill the abdomen.
Feeding by adults
A mosquito has a battery of sensors designed to track their prey,
including chemical, visual, and heat sensors. Typically, both male and
female mosquitoes feed on
nectar and plant juices, but in many species the mouthparts of the
females are adapted for piercing the skin of animal hosts and
sucking their blood as
ectoparasites. In many species, the female needs to obtain nutrients
from a blood meal before she can produce eggs, whereas in many other
species, she can produce more eggs after a blood meal. Both plant
materials and blood are useful sources of energy in the form of sugars,
and blood also supplies more concentrated nutrients, such as
lipids,
but the most important function of blood meals is to obtain proteins as
materials for egg production.
For females to risk their lives on blood sucking while males abstain
is not a strategy limited to the mosquitoes; it also occurs in some
other insect families, such as the
Tabanidae. When a female reproduces without such parasitic meals,
she is said to practice autogenous reproduction, as in
Toxorhynchites; otherwise, the reproduction may be termed
anautogenous, as occurs in mosquito species that serve as disease
vectors, particularly Anopheles and some of the most important
disease vectors in the genus Aedes. In contrast, some mosquitoes,
for example, many Culex, are partially anautogenous; they
do not need a blood meal for their first cycle of egg production, which
they produce autogenously; however, subsequent clutches of eggs are
produced anautogenously, at which point their disease vectoring activity
becomes operative.[24]
Here an Anopheles stephensi female is gorged with blood and
beginning to pass unwanted liquid fractions of the blood to
make room for more of the solid nutrients in her gut
With regard to
host location, female mosquitoes hunt their blood host by detecting
organic substances such as
carbon dioxide (CO2) and
1-octen-3-ol produced from the host, and through optical
recognition. Mosquitoes prefer some people over others. The preferred
victim's sweat simply smells better than others because of the
proportions of the carbon dioxide,
octenol and other compounds that make up body odor.[25]
The most powerful
semiochemical that triggers the keen sense of smell of
Culex
quinquefasciatus is
nonanal.[26]
A large part of the mosquito’s sense of smell, or olfactory system, is
devoted to sniffing out blood sources. Of 72 types of odor receptors on
its antennae, at least 27 are tuned to detect chemicals found in
perspiration.[27]
In Aedes, the search for a host takes place in two phases. First,
the mosquito exhibits a nonspecific searching behavior until the
perception of host stimulants, then it follows a targeted approach.[28]
Most mosquito species are
crepuscular (dawn
or dusk)
feeders. During the heat of the day, most mosquitoes rest in a cool
place and wait for the evenings, although they may still bite if
disturbed.[29]
Some species, such as the
Asian tiger mosquito, are known to fly and feed during daytime.[citation
needed]
Prior to and during blood feeding, blood-sucking mosquitoes inject
saliva into the bodies of their source(s) of blood. This saliva serves
as an
anticoagulant; without it one might expect the female mosquito's
proboscis to become clogged with blood clots. The saliva also is the
main route by which mosquito physiology offers passenger pathogens
access to the hosts' interior. Not surprisingly the salivary glands are
a major target to most pathogens, whence they find their way into the
host via the stream of saliva.
The bump left on the victim's skin after a mosquito bites is called a
wheal, which is caused by histamines trying to fight off the protein
left by the attacking insect.[30]
Mosquitoes of the genus
Toxorhynchites never drink blood.[31]
This genus
includes the largest extant mosquitoes, the larvae of which prey on the
larvae of other mosquitoes. These mosquito eaters have been used in the
past as mosquito control agents, with varying success.[32]
Mouthparts
Mosquito mouthparts are very specialized, particularly those of the
females, which in most species are adapted to piercing skin and then
sucking blood. Apart from bloodsucking, the females generally also drink
assorted fluids rich in dissolved sugar, such as nectar and honeydew, to
obtain the energy they need. For this, their blood-sucking mouthparts
are perfectly adequate. In contrast, male mosquitoes are not
bloodsuckers; they only drink such sugary fluids as they can find.
Accordingly, their mouthparts do not require the same degree of
specialization as those of females.[33]
Externally, the most obvious feeding structure of the mosquito is the
proboscis. More specifically, the visible part of the proboscis is the
labium, which forms the sheath enclosing the rest of the mouthparts.
When the mosquito first lands on a potential host, her mouthparts will
be enclosed entirely in this sheath, and she will touch the tip of the
labium to the skin in various places. Sometimes, she will begin to bite
almost straight away, while other times, she will prod around,
apparently looking for a suitable place. Occasionally, she will wander
for a considerable time, and eventually fly away without biting.
Presumably, this probing is a search for a place with easily accessible
blood vessels, but the exact mechanism is not known. It is known that
there are two taste receptors at the tip of the labium, which may well
play a role.[34]
The female mosquito does not insert her labium into the skin; it
bends back into a bow when the mosquito begins to bite. The tip of the
labium remains in contact with the skin of the victim, acting as a guide
for the other mouthparts. In total, there are six mouthparts besides the
labium: two
mandibles, two
maxillae, the
hypopharynx, and the
labrum.
The mandibles and the maxillae are used for piercing the skin. The
mandibles are pointed, while the maxillae end in flat, toothed "blades".
To force these into the skin, the mosquito moves its head backwards and
forwards. On one movement, the maxillae are moved as far forward as
possible. On the opposite movement, the mandibles are pushed deeper into
the skin by levering against the maxillae. The maxillae do not slip back
because the toothed blades grip the skin.
The hypopharynx and the labrum both are hollow. Saliva with
anticoagulant is pumped down the hypopharynx to prevent clotting, and
blood is drawn up the labrum.
To understand the mosquito mouthparts, it is helpful to draw a
comparison with an insect that chews food, such as a
dragonfly. A dragonfly has two mandibles, which are used for
chewing, and two maxillae, which are used to hold the food in place as
it is chewed. The labium forms the floor of the dragonfly's mouth, the
labrum forms the top, while the hypopharynx is inside the mouth and is
used in swallowing. Conceptually, then, the mosquito's proboscis is an
adaptation of the mouthparts that occur in other insects. The labium
still lies beneath the other mouthparts, but also enfolds them, and it
has been extended into a proboscis. The maxillae still "grip" the "food"
while the mandibles "bite" it. The top of the mouth, the labrum, has
developed into a channeled blade the length of the proboscis, with a
cross-section like an inverted "U". Finally, the hypopharynx has
extended into a tube that can deliver saliva at the end of the
proboscis. Its upper surface is somewhat flattened so, when pressed
against it, the labrum forms a closed tube for conveying blood from the
victim.[35]
Saliva
For the mosquito to obtain a blood meal, it must circumvent the
vertebrate physiological responses. The mosquito, as with all
blood-feeding
arthropods, has mechanisms to effectively block the
hemostasis system with their saliva, which contains a mixture of
secreted proteins. Mosquito saliva negatively affects
vascular constriction,
blood clotting,
platelet aggregation,
angiogenesis and
immunity, and creates
inflammation.[36]
Universally, hematophagous arthropod saliva contains at least one
anticlotting, one antiplatelet, and one vasodilatory substance. Mosquito
saliva also contains enzymes that aid in sugar feeding[37]
and
antimicrobial agents to control bacterial growth in the sugar meal.[38]
The composition of mosquito saliva is relatively simple, as it usually
contains fewer than 20 dominant
proteins.[39]
Despite the great strides in knowledge of these molecules and their role
in bloodfeeding achieved recently, scientists still cannot ascribe
functions to more than half of the molecules found in
arthropod saliva.[39]
One promising application is the development of anticlotting drugs, such
as clotting inhibitors and capillary dilators, that could be useful for
cardiovascular disease.
It is now well recognized that feeding
ticks,
sandflies, and, more recently, mosquitoes, have an ability to
modulate the
immune response of the animals (hosts) on which they feed.[36]
The presence of this activity in vector saliva is a reflection of the
inherent overlapping and interconnected nature of the host hemostatic
and inflammatory/immunological responses and the intrinsic need to
prevent these host defenses from disrupting successful feeding. The
mechanism for mosquito saliva-induced alteration of the host immune
response is unclear, but the data have become increasingly convincing
that such an effect occurs. Early work described a factor in saliva that
directly suppresses
TNF-α release, but not antigen-induced
histamine secretion, from activated
mast cells.[40]
Experiments by Cross et al. (1994) demonstrated the inclusion of Ae.
aegypti mosquito saliva into naïve cultures led to a suppression of
interleukin (IL)-2 and
IFN-γ production, while the cytokines
IL-4 and
IL-5 are unaffected by mosquito saliva.[41]
Cellular proliferation in response to IL-2 is clearly reduced by prior
treatment of cells with SGE.[41]
Correspondingly, activated
splenocytes isolated from mice fed upon by either Ae. aegypti
or Cx. pipiens mosquitoes produce markedly higher levels of IL-4
and
IL-10 concurrent with suppressed IFN-γ production.[42]
Unexpectedly, this shift in cytokine expression is observed in
splenocytes up to 10 days after mosquito exposure, suggesting natural
feeding of mosquitoes can have a profound, enduring, and systemic effect
on the immune response.[42]
T cell
populations are decidedly susceptible to the suppressive effect of
mosquito saliva, showing increased mortality and decreased division
rates.[43]
Parallel work by Wasserman et al. (2004) demonstrated that T- and
B-cell proliferation was inhibited in a dose dependent manner with
concentrations as low as 1/7 of the saliva in a single mosquito.[44]
Depinay et al. (2005) observed a suppression of antibody-specific T cell
responses mediated by mosquito saliva and dependent on mast cells and
IL-10 expression.[45]
A recent study suggests mosquito saliva can also decrease expression
of
interferon−α/β during early mosquito-borne virus infection.[46]
The contribution of type I interferons (IFN) in recovery from infection
with viruses has been demonstrated in vivo by the therapeutic and
prophylactic effects of administration of IFN-inducers or IFN,[47]
and recent research suggests mosquito saliva exacerbates
West Nile virus infection,[48]
as well as other mosquito-transmitted viruses.[49]
Egg development and blood digestion
Female mosquitoes use two very different food sources. They need
sugar for energy, which is taken from sources such as nectar, and they
need blood as a source of protein for egg development. Because biting is
risky and hosts may be difficult to find, mosquitoes take as much blood
as possible when they have the opportunity. This, however, creates
another problem. Digesting that volume of blood takes a while, and the
mosquito will require energy from sugar in the meantime.
To avoid this problem, mosquitoes have a digestive system which can
store both food types, and give access to both as they are needed. When
the mosquito drinks a sugar solution, it is directed to a crop. The crop
can release sugar into the stomach as it is required. At the same time,
the stomach never becomes full of sugar solution, which would prevent
the mosquito taking a blood meal if it had the chance.
Blood is directed straight into the mosquito's stomach. In species
that feed on mammalian or avian blood, hosts whose blood pressure is
high, the mosquito feeds selectively from active blood vessels, where
the pressure assists in filling the gut rapidly. If, instead of slapping
a feeding mosquito, one stretches one's skin so that it grips the
proboscis and the mosquito cannot withdraw it, the pressure will distend
the gut until it breaks and the mosquito dies.[50][better source needed]
In the unmolested mosquito, however, the mosquito will withdraw, and as
the gut fills up, the stomach lining secretes a
peritrophic membrane that surrounds the blood. This membrane keeps
the blood separate from anything else in the stomach. However, like
certain other insects that survive on dilute, purely liquid diets,
notably many of the
Homoptera, many adult mosquitoes must excrete unwanted aqueous
fractions even as they feed. (See the photograph of a feeding
Anopheles stephensi: Note that the excreted droplet patently is not
whole blood, being far more dilute). As long as they are not disturbed,
this permits mosquitoes to continue feeding until they have accumulated
a full meal of nutrient solids. As a result, a mosquito replete with
blood can continue to absorb sugar, even as the blood meal is slowly
digested over a period of several days.[34]
Once blood is in the stomach, the midgut of the female synthesizes
proteolytic enzymes that hydrolyze the blood proteins into free amino
acids. These are used as building blocks for the synthesis of egg yolk
proteins.
In the mosquito
Anopheles stephensi Liston, trypsin activity is restricted
entirely to the posterior midgut lumen. No trypsin activity occurs
before the blood meal, but activity increases continuously up to 30
hours after feeding, and subsequently returns to baseline levels by 60
hours. Aminopeptidase is active in the anterior and posterior midgut
regions before and after feeding. In the whole midgut, activity rises
from a baseline of approximately three enzyme units (EU) per midgut to a
maximum of 12 EU at 30 hours after the blood meal, subsequently falling
to baseline levels by 60 hours. A similar cycle of activity occurs in
the posterior midgut and posterior midgut lumen, whereas aminopeptidase
in the posterior midgut epithelium decreases in activity during
digestion. Aminopeptidase in the anterior midgut is maintained at a
constant, low level, showing no significant variation with time after
feeding. Alpha-glucosidase is active in anterior and posterior midguts
before and at all times after feeding. In whole midgut homogenates,
alpha-glucosidase activity increases slowly up to 18 hours after the
blood meal, then rises rapidly to a maximum at 30 hours after the blood
meal, whereas the subsequent decline in activity is less predictable.
All posterior midgut activity is restricted to the posterior midgut
lumen. Depending on the time after feeding, greater than 25% of the
total midgut activity of alpha-glucosidase is located in the anterior
midgut. After blood meal ingestion, proteases are active only in the
posterior midgut. Trypsin is the major primary hydrolytic protease and
is secreted into the posterior midgut lumen without activation in the
posterior midgut epithelium. Aminoptidase activity is also luminal in
the posterior midgut, but cellular aminopeptidases are required for
peptide processing in both anterior and posterior midguts.
Alpha-glucosidase activity is elevated in the posterior midgut after
feeding in response to the blood meal, whereas activity in the anterior
midgut is consistent with a nectar-processing role for this midgut
region.[51]
Distribution
Mosquitoes are very widespread, occurring in all regions of the world
except for Antarctica.[34]
In warm and humid tropical regions, they are active for the entire year,
but in temperate regions, they hibernate over winter. Arctic mosquitoes
may be active for only a few weeks as pools of water form on top of the
permafrost. During that time, though, they exist in huge numbers and can
take up to 300 ml of blood per day from each animal in a caribou herd.[11]
Only Iceland does not have mosquitoes.
[52]
Eggs from strains in the
temperate zones are more tolerant to the cold than ones from warmer
regions.[53][54]
They can even tolerate snow and subzero temperatures. In addition,
adults can survive throughout winter in suitable microhabitats.[55]
Means of dispersal
Worldwide introduction of various mosquito species over large
distances into regions where they are not indigenous has occurred
through human agencies, primarily on sea routes, in which the eggs,
larvae, and pupae inhabiting water-filled used tires and cut flowers are
transported. However, apart from sea transport, mosquitoes have been
effectively carried by personal vehicles, delivery trucks, trains, and
aircraft. Sufficient quarantine measures have proven difficult to
implement.
Disease
Anopheles albimanus mosquito feeding on a human arm
– this mosquito is a vector of
malaria, and mosquito control is a very effective way of
reducing the incidence of malaria.
Mosquitoes can act as
vectors for many disease-causing
viruses
and
parasites. Infected mosquitoes carry these organisms from person to
person without exhibiting symptoms themselves. Mosquito-borne diseases
include:
- Viral diseases, such as
yellow fever,
dengue fever and
chikungunya, transmitted mostly by
Aedes aegypti. Dengue fever is the most common cause of
fever in travelers returning from the Caribbean, Central America,
and South Central Asia. This disease is spread through the bites of
infected mosquitoes and cannot be spread person to person.
Severe dengue can be fatal, but with good treatment, less than 1% of
patients die from dengue.
Potential transmission of
HIV was
originally a public health concern, but practical considerations and
detailed studies of epidemiological patterns suggest that any
transmission of the HIV virus by mosquitoes is at worst extremely
unlikely.[58]
Various species of mosquitoes are estimated to transmit various types
of disease to more than 700 million people annually in Africa, South
America, Central America, Mexico, Russia, and much of Asia, with
millions of resultant deaths. At least two million people annually die
of these diseases, and the
morbidity
rates are many times higher still.
Methods used to prevent the spread of disease, or to protect
individuals in areas where disease is endemic, include:
Since most such diseases are carried by "elderly" female mosquitoes,
some scientists have suggested focusing on these to avoid the evolution
of resistance.[59]
Control
Many methods are used for mosquito control. Depending on the
situation, the most important usually include:
- source reduction (e.g., removing stagnant water)
- biocontrol (e.g. importing natural predators such as
dragonflies)
- trapping, and/or insecticides to kill
larvae or adults
- exclusion (mosquito nets and window screening)
Source reduction
World War II era pamphlet aimed to discourage creation of
stagnant water
Source reduction means elimination of breeding places of
mosquitoes. It includes engineering measures such as filling, leveling
and drainage of breeding places, and water management (such as
intermittent irrigation). Source reduction can also be done by making
water unsuitable for mosquitoes to breed, for example, by changing
salinity of water. Some specific measures are:
- For Culex: abolition of domestic and peridomestic sources
of water suitable for breeding, for example removal and disposal of
sewage and other waste water
- For Aedes: eliminating incidental containers such as
discarded tins, crockery, pots, broken bottles, and coconut shells
- For Anopheles: abolish breeding places by filling or
drainage
- For Mansonia: removal of aquatic plants manually or by
application of herbicides
Details of the biology of different species of mosquitoes differ too
widely for any limited set of rules to be sufficient in all
circumstances. However, the foregoing are the most economical and
practical measures for most purposes. The importance of peridomestic
control arises largely because most species of mosquitoes rarely travel
more than a few hundred meters unless the wind is favorable.
Exclusion
In combination with scrupulous attention to control of breeding
areas,
window screens and
mosquito nets are the most effective measures for residential areas.
Insecticide-impregnated mosquito nets are particularly effective
because they selectively kill those insects that attack humans, without
affecting the general ecology of the area.
An ideal mosquito net is white in color (to allow easy detection of
mosquitoes), rectangular, netted on sides and top, without a hole. The
size of opening in net should not exceed 1.2 mm (0.05 in) in diameter,
or about 23 holes per square centimeter (150 per square inch). Window
screens should have copper or bronze gauze with 16 wires per inch.
Natural predators
Dragonfly and
damselfly nymphs and various other aquatic insect predators eat
mosquitoes at all stages of development and dense populations can be
useful in reducing mosquito problems.[60]
Various small fishes, such as species of
Galaxias and members of the
Poeciliidae, such as
Gambusia (so-called mosquitofish) and
guppies (Poecilia),
eat mosquito larvae and sometimes may be worth introducing into ponds to
assist in control.[61]
Many other types of fish are also known to consume mosquito larvae,
including
bass,
bluegills,
piranhas,
Arctic char,
salmon,
trout,
catfish,
fathead minnows,
goldfish, and
killifish.
Although bats
and
purple martins can be prodigious consumers of insects, many of which
are pests, less than 1% of their diets typically consist of mosquitoes.
Neither bats nor purple martins are known to control or even
significantly reduce mosquito populations.[62]
Some
cyclopoid
copepods are predators on first-instar larvae, killing up to 40
Aedes larvae per day.[63]
Larvae of the non-biting
Toxorhynchites mosquitoes also are natural predators of other
Culicidae. Each larva can eat 10 to 20 mosquito larvae per day. During
its entire development, a Toxorhynchites larva can consume an
equivalent of 5,000 larvae of the first-instar (L1) or 300 fourth-instar
larvae (L4).[64][65]
However, Toxorhynchites can consume all types of prey, organic
debris, or even exhibit cannibalistic behavior.
Other natural
predators and
parasitoids include fungi[66]
and nematodes.[67]
Though important at times, their effectiveness varies with
circumstances.
Bacillus thuringiensis israelensis has also been used to control
them as a biological agent.
Mosquito
bites and treatment
Video of a mosquito biting on leg
Visible, irritating bites are due to an
immune response from the binding of
IgG and
IgE
antibodies to
antigens in the mosquito's
saliva.
Some of the sensitizing antigens are common to all mosquito species,
whereas others are specific to certain species. There are both immediate
hypersensitivity reactions (types I and III) and delayed
hypersensitivity reactions (type IV) to mosquito bites.[68]
Both reactions result in itching, redness and swelling. Immediate
reactions develop within a few minutes of the bite and last for a few
hours. Delayed reactions take around a day to develop, and last for up
to a week. Several
anti-itch medications are commercially available, including those
taken orally, such as
Benadryl, or topically applied
antihistamines and, for more severe cases,
corticosteroids, such as
hydrocortisone and
triamcinolone.
Tea tree oil has been shown to be an effective anti-inflammatory,
reducing itching.[69]
Repellents
Insect repellents are applied on skin and give short-term protection
against mosquito bites. The chemical
DEET repels
some mosquitoes and other insects.[70]
Some CDC-recommended repellents are
picaridin,
eucalyptus oil (PMD)
and IR3535.[71]
Others are indalone, dimethyl pthalate,
dimethyl carbate, and ethyl hexanediol.
Evolution
The oldest known mosquito with an anatomy similar to modern species
was found in 79-million-year-old Canadian
amber
from the
Cretaceous.[72]
An older sister species with more primitive features was found in amber
that is 90 to 100 million years old.[73]
Two mosquito fossils have been found that show very little morphological
change in modern mosquitoes against their counterpart from 46 million
years ago.[74]
Genetic analyses indicate the Culicinae and Anophelinae clades may
have diverged about 150 million years ago.[75]
The Old and New World Anopheles species are believed to have
subsequently diverged about 95 million years ago.[75]
The mosquito
Anopheles gambiae is currently undergoing speciation into the
M(opti) and S(avanah) molecular forms. This means some pesticides that
work on the M form will not work anymore on the S form.[76]
Taxonomy of
the Culicidae
Over 3,500 species of the Culicidae have already been described.[77]
They are generally divided into two subfamilies which in turn comprise
some 43 genera. These figures are subject to continual change, as more
species are discovered, and as DNA studies compel rearrangement of the
taxonomy of the family. The two main subfamilies are the Anophelinae and
Culicinae, with their genera as shown in the subsection below.[78]
Subfamilies
and genera
Anophelinae
Culicinae
References
-
^
Harbach,
Ralph (November 2, 2008).
"Family Culicidae Meigen, 1818". Mosquito Taxonomic
Inventory.
-
^
"Mosquitoes of Michigan -Their Biology and Control".
Michigan Mosquito Control Organization. 2013.
-
^
Jaeger, Edmund C. (1959). A Source-Book of Biological
Names and Terms. Springfield, Ill: Thomas.
ISBN 0-398-06179-3.
-
^
Brown, Lesley (1993). The New
shorter Oxford English dictionary on historical principles.
Oxford [Eng.]: Clarendon.
ISBN 0-19-861271-0.
-
^
Biological notes on mosquitoes. Mosquitoes.org. Retrieved on
2013-04-01.
-
^
Taking a bite out of mosquito research, Author Paul Leisnham,
University of Maryland. Enst.umd.edu (2010-07-26). Retrieved
on 2013-04-01.
-
^
Molavi,
Afshin (June 12, 2003).
"Africa's Malaria Death Toll Still "Outrageously High"".
National Geographic.
Retrieved July 27, 2007.
-
^
"Mosquito-borne diseases". American Mosquito Control
Association. Retrieved
October 14, 2008.
-
^
World Health Organisation.
Flooding and communicable diseases fact sheet.
-
^
Wilcox, B.A. & Ellis, B. (2006).
"Forests and emerging infectious diseases of humans".
Unasylva 57.
ISSN 0041-6436.
- ^
a
b
Fang, Janet (July 21, 2010). "Ecology: A world without
mosquitoes". Nature (Nature) 466 (7305): 432–4.
doi:10.1038/466432a.
PMID 20651669.
-
^
"Mosquito Eradication". Science Today – Beyond the
Headlines. California Academy of Sciences. 26.
Retrieved 25 August 2011.
-
^
Wigglesworth V. B. (1933).
"The Adaptation of Mosquito Larvae to Salt Water". J Exp
Biol 10: 27–36.
-
^
Crans, Wayne J.;
Wyeomyia smithii (Coquillett). Rutgers University,
Center for Vector Biology.
-
^
Kosova, Jonida (2003)
"Longevity Studies of Sindbis Virus Infected Aedes Albopictus".
All Volumes (2001–2008). Paper 94.
-
^
Michigan Mosquito Control
Association; Michigan Mosquito Manual, MMCA Edition. Pub.
Michigan Department of Agriculture June 2002
-
^
a
b
Spielman, Andrew; D'Antonio, M. (2001). Mosquito : a natural
history of our most persistent and deadly foe. New York:
Hyperion.
ISBN 978-0-7868-6781-3.
-
^
Huang, Juan. Walker, Edward D.
Vulule, John. Miller,James R. ; Daily temperature profiles in
and around Western Kenyan larval habitats of Anopheles gambiae
as related to egg mortality. Malaria Journal 2006, 5:87
doi:10.1186/1475-2875-5-87
-
^
"Mosquito".
Virginia Tech. Retrieved
May 19, 2007.
-
^
a
b
Harzsch, S.; Hafner, G. (2006). "Evolution of eye development in
arthropods: Phylogenetic aspects". Arthropod Structure and
Development 35 (4): 319–340.
doi:10.1016/j.asd.2006.08.009.
PMID 18089079.
-
^
Kaufmann C and Briegel H (2004).
"Flight performance of the malaria vectors Anopheles gambiae
and Anopheles atroparvus" (PDF).
Journal of Vector Ecology 29 (1): 140–153.
PMID 15266751.
Retrieved June 21, 2009.
-
^
Frequency of Mosquito Wings. Hypertextbook.com (2000-05-31).
Retrieved on 2013-04-01.
-
^
African Safari Travel Blog » Blog Archive » Facts you may not
know about mosquitoes. Safari.co.uk (2011-07-05). Retrieved
on 2013-04-01.
-
^
Sawabe, K.; Moribayashi, A. (2000). "Lipid utilization for
ovarian development in an autogenous mosquito, Culex pipiens
molestus (Diptera: Culicidae)". Journal of medical entomology
37 (5): 726–731.
doi:10.1603/0022-2585-37.5.726.
PMID 11004785. edit
-
^
Elissa A. Hallem; Nicole Fox, A.; Zwiebel, Laurence J.; Carlson,
John R. (2004). "Olfaction: Mosquito receptor for human-sweat
odorant".
Nature 427 (6971): 212–213.
doi:10.1038/427212a.
PMID 14724626.
-
^
"Scientists identify key smell that attracts mosquitoes to
humans".
US News. October 28, 2009.
-
^
Devlin,
Hannah (February 4, 2010).
"Sweat and blood why mosquitoes pick and choose between humans".
London: The Times. Retrieved
May 13, 2010.
-
^
Estrada-Franco, R. G. and Craig, G.
B. (1995). Biology, disease relationship and control of
Aedes albopictus. Technical Paper No. 42. Washington, D.C.: Pan
American Health Organization.
-
^
Wayne J. Crans (1989).
"Resting boxes as mosquito surveillance tools". Proceedings
of the Eighty-Second Annual Meeting of the New Jersey Mosquito
Control Association. pp. 53–57.
-
^
http://www.washingtonpost.com/wp-dyn/content/article/2007/07/27/AR2007072702155.html
-
^
Jones, C. and Schreiber, E. (1994).
"The carnivores, Toxorhynchites". Wing Beats
5 (4): 4.
-
^
"Site down for maintenance". Pestscience.com.
Retrieved 2011-05-31.
-
^
Wahid, I.; Sunahara, T.; Mogi, M.
(2003). "Maxillae and mandibles of male mosquitoes and female
autogenous mosquitoes (Diptera: Culicidae)". Journal of
medical entomology 40 (2): 150–158.
doi:10.1603/0022-2585-40.2.150.
PMID 12693842. edit
-
^
a
b
c
Mullen,
Gary; Durden, Lance (2009). Medical and Veterinary Entomology.
London: Academic Press.
-
^
Richards, O. W.; Davies, R.G.
(1977). Imms' General Textbook of Entomology: Volume 1:
Structure, Physiology and Development Volume 2: Classification
and Biology. Berlin: Springer.
ISBN 0-412-61390-5.
-
^
a
b
Ribeiro, J. M. & Francischetti, I. M. (2003). "Role of arthropod
saliva in blood feeding: sialome and post-sialome perspectives".
Annual Review of Entomology 48: 73–88.
doi:10.1146/annurev.ento.48.060402.102812.
PMID 12194906.
-
^
Grossman G. L. & James, A. A. (1993). "The salivary glands of
the vector mosquito, Aedes aegypti, express a novel
member of the amylase gene family".
Insect Molecular Biology 1 (4): 223–232.
doi:10.1111/j.1365-2583.1993.tb00095.x.
PMID 7505701.
-
^
Rossignol, P. A. & Lueders, A. M. (1986). "Bacteriolytic factor
in the salivary glands of Aedes aegypti".
Comparative Biochemistry and Physiology B 83 (4):
819–822.
doi:10.1016/0305-0491(86)90153-7.
PMID 3519067.
-
^
a
b
Valenzuela, J. G., Pham, V. M., Garfield, M. K., Francischetti,
I. M. & Ribeiro, J. M. (2002). "Toward a description of the
sialome of the adult female mosquito Aedes aegypti".
Insect Biochemistry and Molecular Biology 32 (9):
1101–1122.
doi:10.1016/S0965-1748(02)00047-4.
PMID 12213246.
-
^
Bissonnette, E. Y., Rossignol, P. A. & Befus, A. D. (1993).
"Extracts of mosquito salivary gland inhibit tumour necrosis
factor alpha release from mast cells".
Parasite Immunology 15 (1): 27–33.
doi:10.1111/j.1365-3024.1993.tb00569.x.
PMID 7679483.
-
^
a
b
Cross ML, Cupp EW, Enriquez FJ (1994). "Differential modulation
of murine cellular immune responses by salivary gland extract of
Aedes aegypti".
American Journal of Tropical Medicine and Hygiene 51
(5): 690–696.
PMID 7985763.
-
^
a
b
Zeidner, N. S., Higgs, S., Happ, C. M., Beaty, B. J. & Miller,
B. R. (1999). "Mosquito feeding modulates Th1 and Th2 cytokines
in flavivirus susceptible mice: an effect mimicked by injection
of sialokinins, but not demonstrated in flavivirus resistant
mice".
Parasite Immunology 21 (1): 35–44.
doi:10.1046/j.1365-3024.1999.00199.x.
PMID 10081770.
-
^
Wanasen, N., Nussenzveig, R. H., Champagne, D. E., Soong, L. &
Higgs, S. (2004). "Differential modulation of murine host immune
response by salivary gland extracts from the mosquitoes Aedes
aegypti and Culex quinquefasciatus".
Medical and Veterinary Entomology 18 (2):
191–199.
doi:10.1111/j.1365-2915.2004.00498.x.
PMID 15189245.
-
^
Wasserman, H. A., Singh, S. & Champagne, D. E. (2004). "Saliva
of the Yellow Fever mosquito, Aedes aegypti, modulates
murine lymphocyte function".
Parasite Immunology 26 (6–7): 295–306.
doi:10.1111/j.0141-9838.2004.00712.x.
PMID 15541033.
-
^
Depinay, N., Hacini, F., Beghdadi, W., Peronet, R., Mécheri, S.
(2006). "Mast cell-dependent down-regulation of antigen-specific
immune responses by mosquito bites".
Journal of Immunology 176 (7): 4141–4146.
PMID 16547250.
-
^
Schneider, B. S., Soong, L., Zeidner, N. S. & Higgs, S. (2004).
"Aedes aegypti salivary gland extracts modulate
anti-viral and TH1/TH2 cytokine responses to sindbis virus
infection". Viral Immunology 17 (4): 565–573.
doi:10.1089/vim.2004.17.565.
PMID 15671753.
-
^
Taylor, J. L., Schoenherr, C. & Grossberg, S. E. (1980).
"Protection against Japanese encephalitis virus in mice and
hamsters by treatment with carboxymethylacridanone, a potent
interferon inducer".
The Journal of Infectious Diseases 142 (3):
394–399.
doi:10.1093/infdis/142.3.394.
PMID 6255036.
-
^
Schneider, B. S., Soong, L., Girard, Y. A., Campbell, G., Mason,
P. & Higgs, S. (2006). "Potentiation of West Nile encephalitis
by mosquito feeding". Viral Immunology 19 (1):
74–82.
doi:10.1089/vim.2006.19.74.
PMID 16553552.
-
^
Schneider, B. S. & Higgs, S. (2008).
"The enhancement of arbovirus transmission and disease by
mosquito saliva is associated with modulation of the host immune
response".
Transactions of the Royal Society of Tropical Medicine and
Hygiene 102 (5): 400–408.
doi:10.1016/j.trstmh.2008.01.024.
PMC 2561286.
PMID 18342898.
-
^
"If you flex your muscle when a mosquito bites you, will it
swell up and explode?". The Straight Dope.
1997-08-22.
-
^
Billingsley, P. F. & Hecker, H.
(1991). "Blood digestion in the mosquito, Anopheles stephensi
Liston (Diptera: Culicidae): activity and distribution of
trypsin, aminopeptidase, and alpha-glucosidase in the midgut".
Journal of Medical Entomology 28 (6): 865–871.
PMID 1770523.
-
^
http://visindavefur.hi.is/svar.php?id=2166
-
^
Hawley, W. A., Pumpuni, C. B., Brady, R. H. & Craig, G. B.
(1989). "Overwintering survival of Aedes albopictus
(Diptera: Culicidae) eggs in Indiana".
Journal of Medical Entomology 26 (2): 122–129.
PMID 2709388.
-
^
Hanson, S. M. & Craig, G. B. (1995). "Aedes albopictus
(Diptera: Culicidae) eggs: field survivorship during northern
Indiana winters".
Journal of Medical Entomology 32 (5): 599–604.
PMID 7473614.
-
^
Romi, R., Severini, F. & Toma, L. (2006). "Cold acclimation and
overwintering of female Aedes albopictus in Roma".
Journal of the American Mosquito Control Association 22
(1): 149–151.
doi:10.2987/8756-971X(2006)22[149:CAAOOF]2.0.CO;2.
PMID 16646341.
-
^
"Lymphatic Filariasis". World Health Organisation (WHO)
website. World Health Organisation (WHO).
Retrieved 24 August 2011.
-
^
Muslu, H.; Kurt, O.; Ozbilgin, A. (2011). "Evaluation of
Mosquito Species (Diptera: Culicidae) Identified in Manisa
Province According to Their Breeding Sites and Seasonal
Differences". Turkish Journal of Parasitology 35
(2): 100.
doi:10.5152/tpd.2011.25.
edit
-
^
"Can I get HIV from mosquitoes?".
CDC. October 20, 2006.
-
^
"Resistance is Useless". The Economist. April 8, 2009.
-
^
Singh, R. K., Dhiman, R. C. & Singh, S. P. (2003). "Laboratory
studies on the predatory potential of dragon-fly nymphs on
mosquito larvae".
Journal of Communicable Diseases 35 (2): 96–101.
PMID 15562955.
-
^
Krumholz, Louis A. (1948). "Reproduction in the Western
Mosquitofish, Gambusia affinis affinis (Baird & Girard),
and Its Use in Mosquito Control". Ecological Monographs
18 (1): 1–43.
doi:10.2307/1948627.
JSTOR 1948627.
-
^
Fradin, M. S. (1 June 1998). "Mosquitoes and mosquito
repellents: a clinician's guide".
Annals of Internal Medicine 128 (11): 931–940.
doi:10.1059/0003-4819-128-11-199806010-00013.
PMID 9634433.
-
^
Marten, G. G. & Reid, J. W. (2007). "Cyclopoid copepods".
Journal of the American Mosquito Control Association 23
(2 Suppl): 65–92.
doi:10.2987/8756-971X(2007)23[65:CC]2.0.CO;2.
PMID 17853599.
-
^
Steffan, W. A.; Evenhuis, N. L. (1981). "Biology of
Toxorhynchites". Annual Review of Entomology 26:
159.
doi:10.1146/annurev.en.26.010181.001111.
edit
-
^
Focks, D. A.; Sackett, S. R.; Bailey, D. L. (1982). "Field
experiments on the control of Aedes aegypti and Culex
quinquefasciatus by Toxorhynchites rutilus rutilus (Diptera:
Culicidae)". Journal of medical entomology 19 (3):
336–339.
PMID 7120310. edit
-
^
Kramer, J. P. (1982). "Entomophthora culicis(Zygomycetes,
Entomophthorales) as a pathogen of adultaedes aegypti(diptera,
culicidae)". Aquatic Insects 4 (2): 73–79.
doi:10.1080/01650428209361085.
edit.
-
^
Shamseldean, M. M.; Platzer, E. G. (1989). "Romanomermis
culicivorax: Penetration of larval mosquitoes". Journal of
Invertebrate Pathology 54 (2): 191–199.
doi:10.1016/0022-2011(89)90028-1.
PMID 2570111.
edit.
-
^
Clements, Alan (1992). The biology of mosquitoes – volume 1:
Development, Nutrition and Reproduction. London: Chapman &
Hall.
ISBN 0-85199-374-5.
-
^
"Anti-inflammatory Activity of Tea Tree Oil". Rural
Industries Research and Development Corporation. February 2001.
Retrieved 2011-06-17.
-
^
Syed, Z.; Leal, W. S. (2008).
"Mosquitoes smell and avoid the insect repellent DEET".
Proceedings of the National Academy of Sciences 105
(36): 13598–13603.
doi:10.1073/pnas.0805312105.
PMC 2518096.
PMID 18711137.
-
^
CDC
(2009).
Updated Information regarding Insect Repellents.
-
^
G.
O. Poinar et al. (2000).
"Paleoculicis minutus (Diptera: Culicidae) n. gen., n.
sp., from Cretaceous Canadian amber with a summary of described
fossil mosquitoes" (PDF).
Acta Geologica Hispanica 35: 119–128.
-
^
Borkent, A. and Grimaldi, D. A. (2004). "The earliest fossil
mosquito (Diptera: Culicidae), in Mid-Cretaceous Burmese amber".
Annals of the Entomological Society of America 97
(5): 882–888.
doi:10.1603/0013-8746(2004)097[0882:TEFMDC]2.0.CO;2.
ISSN 0013-8746.
-
^
Smithsonian ScienceDiscovery of new prehistoric mosquitoes
reveal these blood-suckers have changed little in 46 million
years. Smithsonian Science (2013-01-07). Retrieved on
2013-05-05.
- ^
a
b
Calvo, E., Pham, V. M., Marinotti, O., Andersen, J. F. &
Ribeiro, J. M. (2009).
"The salivary gland transcriptome of the neotropical malaria
vector Anopheles darlingi reveals accelerated evolution of genes
relevant to hematophagy" (PDF).
BMC Genomics 10 (1): 57.
doi:10.1186/1471-2164-10-57.
PMC 2644710.
PMID 19178717.
-
^
Lawniczak, M. K. N.; Emrich, S. J.; Holloway, A. K.; Regier, A.
P.; Olson, M.; White, B.; Redmond, S.; Fulton, L. et al. (2010).
"Widespread Divergence Between Incipient Anopheles gambiae
Species Revealed by Whole Genome Sequences". Science
330 (6003): 512–514.
doi:10.1126/science.1195755.
PMID 20966253.
edit
-
^
Harbach, R.E. (2011).
Mosquito Taxonomic Inventory.
-
^
Walter Reed Biosystematics Unit. Wrbu.si.edu. Retrieved on
2013-04-01.
Further reading
- Brunhes, J.; Rhaim, A.; Geoffroy, B.; Angel, G.; Hervy, J.
P. Les Moustiques de l'Afrique mediterranéenne
French/English. Interactive identification guide to mosquitoes
of North Africa, with database of information on morphology,
ecology, epidemiology, and control. Mac/PC Numerous
illustrations. IRD/IPT [12640] 2000 CD-ROM.
ISBN 2-7099-1446-8
- Davidson, Elizabeth W. (1981).
Pathogenesis of invertebrate microbial diseases.
Montclair, N. J.: Allanheld, Osmun.
ISBN 0-86598-014-4.
- Jahn, G. C., Hall, D. W. &
Zam, S. G. (1986). "A comparison of the life cycles of two
Amblyospora (Microspora: Amblyosporidae) in the mosquitoes
Culex salinarius and Culex tarsalis Coquillett".
Journal of the Florida Anti-Mosquito Association 57:
24–27.
- Kale, H. W., II. (1968).
"The relationship of purple martins to mosquito control"
(PDF).
The Auk 85 (4): 654–661.
doi:10.2307/4083372.
JSTOR 4083372.
External links
|
|
1)
scrivi
le parole inglesi dentro la
striscia gialla 2)
seleziona il testo 3)
clicca "Ascolta il testo"
DA INGLESE A ITALIANO
Inserire
nella casella Traduci la parola
INGLESE e cliccare
Go.
DA ITALIANO A INGLESE
Impostare INGLESE anziché italiano e
ripetere la procedura descritta.
|
|