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There are 50
mosquito species found in Massachusetts;
some are common, and others are found less frequently. Each species has it's own unique combination of characteristics. The
presence of a particular mosquito species is dependent on the type of nearby
wetland or habitat. Examples of different habitats that produce different
mosquito species include permanent swamps, temporary woodland pools, river
flood plains, cattail swamps or artificial containers. The last item can be
almost any container which can hold stagnant water for at least a week in the
summer, including roadside highway drains, old rimless tires, unused swimming
pools, uncovered empty trash cans, and bird baths.
The species of
mosquito found at any one time in an area is dependent on temperature and
season; there are early spring, late spring, summer, and mid-summer species.
Some mosquito species have several generations each summer, so their
populations increase as the summer goes along. Most mosquito species are
active primarily during dusk and dawn or during cloudy warm days. However,
one local species is active all night and some species will bite during hot
sunny days. Three of our local mosquito species will enter protected shelters
such as houses, and it is usually one of these three species that annoy
people while they are trying to sleep.
While some
mosquitoes are indiscriminate about what they bite, most are selective. Some
of our mosquito species feed primarily on humans and other mammals, while
others mostly bite birds, and still others feed on amphibians (such as frogs)
or reptiles (such as snakes). Some species are very aggressive and
persistent, while others are very shy. Finally, some deliver a more annoying
bite that results in more itching.
The chance of
acquiring a mosquito-borne disease in Massachusetts
is extremely rare. However, the species which are believed to transmit
Eastern Equine Encephalitis include some of the most numerous species, which
on given nights can be caught on any suburban or rural property in eastern or
central Massachusetts.
West Nile Virus has been introduced into our area in the year 2000, and
continued research is showing many species of mosquito, including human
biters, adept at carrying and possibly transmitting this disease. Mosquitoes
also transmit animal diseases, and the probability of a pet dog or cat
acquiring heartworm is not so remote. It is recommended that a veterinarian
monitor your pet and administer the proper preventative medication.
Please note:
the sub-genus Ochlerotatus has been elevated to genus, thus affecting
most of the Aedes classifications.
- Aedes albopictus - Aedes albopictus was first collected
in the United States
at a tire dump near Houston,
TX in 1985. The species
spread rapidly through the southern United States and has been
documented in over 25 states over the last decade. The first record of
this species in Mass.
was documented in 2000. Aedes albopictus is a multi-voltine species and should have a seasonal
distribution similar to that of Ochlerotatus triseriatus. Ae. albopictus is an opportunistic container breeder
that is capable of utilizing natural as well as artificial container
habitats. Although the mosquito is most often associated with discarded
tires in this country, it has the ability to adapt to an exceptionally
wide range of confined water sources. The mosquito is known for its
ability to survive in very small collections of water, requiring only
1/4" of depth to complete its life cycle.
- Aedes cinereus - Common late spring and early summer
mosquito pest of humans and other mammals. Larvae are found in late
April and May in tussock and leather-leaf marshes.
- Aedes vexans - Very common summer mosquito. This pest of
humans and other mammals can have several generations each season, so the population may increase during the
summer. Larvae are found in a wide variety of temporary pools and
wetlands. This mosquito is a suspect in the transmission of EEE from
birds to humans. After significant rain events, this mosquito can be
quite numerous and is considered a major pest of man. West Nile Virus
has been isolated from this species in 2000.
- Anopheles barberi - A tree hole breeding mosquito in eastern North America. The larvae are predators of other
mosquito larvae. It has been shown to be a vector of malaria in the
laboratory, but it is not thought to be an important malaria vector in
the wild.
- Anopheles crucians - A mosquito that breeds in semi-permanent
and permanent pools, ponds, lakes and swamps. It may be a vector for
malaria in certain areas.
- Anopheles earlei - Larvae are found in cold, clear water at
the margins ponds and pools containing emergent and floating vegetation.
They are also found in woodland pools, bogs, marshes and along sluggish
streams. Females are dusk- and early-evening biters and will enter
houses to bite.
- Anopheles punctipennis - Found occasionally in the spring and
summer. This pest of humans and other mammals has a mildly annoying bite.
The larvae are found in a wide variety of wetlands including permanent
swamps and along the edges of ponds and slow moving streams. West Nile
Virus has been isolated from this species in 2000.
- Anopheles quadrimaculatus - Common Summer mosquito. A pest of humans
and other mammals that readily enters houses and has a mildly annoying
bite. The population increases during the summer. The larvae are found
in clear water amongst low vegetation or floating debris, in permanent
swamps, and along the edges of ponds and slow moving streams.
- Anopheles walkeri - The larvae of this species occur in
fresh-water marshes containing emergent or floating vegetation. It is
reported that cut-grass shaded by willows or button bushes off the most
ideal larval habitat. Adults have been found resting in dark extremely
moist situations, particularly around the shaded bases of cut-grass and
other shore-line shrubbery.
- Coquillettidia perturbans - Very common mid-June to mid-August
mosquito. An indiscriminate pest of birds, humans and other mammals that
is known to be a vicious biter, and will readily enter homes. The larvae
are unusual in that they are found attached to the submerged roots of
cattails and a few other aquatic plants. This trait makes this species
impervious to control using pesticides that are effective against larvae
of other species. This mosquito is suspected in the transmission of EEE
from birds to humans.
- Culex pipiens - Very common year round mosquito which
primarily feeds on birds. It will readily enter a house, but is
considered shy. It will typically only bite people when they are
motionless, usually while they are sleeping. The larvae are found in
water holding containers and in polluted waters. Culex pipiens
are considered the primary vector of West Nile Virus. West Nile Virus has
been isolated from this species.
- Culex restuans - Culex restuans has a distribution
that ranges from central Canada
south into Mexico.
The mosquito is very common in the eastern and central United States.
Culex restuans undergoes a life cycle that is typical for
domestic Culex. Inseminated adult females enter hibernation in
fall and pass the winter in a period of quiescence. Culex restuans
utilizes an exceptionally wide range of larval habitats. The water used
by this species can vary from nearly clear to grossly polluted.
Culex restuans regularly colonizes temporary ground pools that
remain flooded after they have produced broods of floodwater Ochlerotatus.
Culex restuans is also the first species to utilize water that
collects in discarded tires. The species can often be found in tire
water that is absolutely clear and devoid of leaf litter.
- Culex salinarius - Common summer mosquito. A fierce biting
pest of birds, humans and other mammals which can have several
generations in a summer, so the population may increase during the
season. This mosquito is active all night. Larvae are found in both
fresh and polluted grassy hummock areas of permanent water swamps. West
Nile Virus has been isolated from this species in 2000.
- Culex territans - Culex territans is quite common
throughout most of eastern Europe and is even
found in parts of Africa. In North
America, Cx. territans extends from Alaska
and Canada south
through most of the United
States. Culex territans has a
life cycle that is typical for most Culex species. In late fall,
inseminated adult females feed on carbohydrates and hibernate in
subterranean enclosures where they pass the winter in a state of torpor.
The mosquitoes emerge in very early spring, obtain a blood meal and lay
the first egg rafts of the season. Culex territans is a frog
feeder and it is not uncommon to see this species feeding on Spring
Peepers. Egg hatch, however, may be delayed because of the mosquito's
unique oviposition habits. Unlike most Culex, Cx. territans
females rarely deposit their egg rafts directly on the surface of the
water. This mosquito normally positions the raft up on the bank and
relies on rainfall or rising water levels to flush the eggs onto the
water's surface. Culex territans shares habitat with many of the univoltine Ochlerotatus in early spring, a
variety of Anopheles sp. later in the summer and Uranotaenia sapphirina very late in the season. The species
is occasionally found in containers but cannot tolerate even moderate
levels of pollution. Culex territans is common in farm ponds,
swamps and bogs and roadside ditches. Culex territans is one of
the few species that can be collected from streams. It is not uncommon
to find larvae within the grassy margins of slow moving streams and
specimens are sometimes found in rock pool habitats normally associated
with Ochlerotatus atropalpus.
- Culiseta inornata - Larvae found in a wide range of habitats
including marshes, seepages, ditches, canals ponds, etc. Larvae can tolerate water with a salinity up to 26 ppt. Biting activity on overcast days, dusk
and at night. Flight range is
less than five miles.
- Culiseta melanura - Common spring and summer mosquito. A bird-
feeding mosquito that can have several generations per year, so the population
may increase towards the end of the summer. Larvae are found in holes in
the root structures of white cedar and red maple trees in swamps. This
is an important mosquito species because it is believed to spread EEE
virus through the bird population. This mosquito was not thought to be a
mammal-biter, but recent research has shown a small percentage of it’s bloodmeals are taken from mammals.
- Culiseta morsitans - Culiseta morsitans
is a mosquito of the northern United
States with a distribution that extends through
Canadian Yukon Territory into Alaska.
The mosquito is fairly common in New England and upper New York state.
Records from the Atlantic coast region indicate that the species has
been collected as far south as Delaware.
Culiseta morsitans has a life cycle
similar to that of the northern Ochlerotatus group of mosquitoes.
The species is considered univoltine but
females are long lived and frequently appear in light trap collections
well into the summer. Unlike most members of the Genus Culiseta,
the egg rafts are deposited on damp earth, probably deep within the Carex tussocks that are so common in their
breeding habitat. Mature stands of red maple that grow in 12-18" of
early spring ground water provide typical habitat. Uprooted trees are
common in many of the swamps that support this species and tussocks of
Carex serve as indicators of the
semi-permanent nature of the habitat
- Ochlerotatus abserratus - Very common early spring to early summer
mosquito pest of humans and other mammals. Larvae are found in temporary
spring pools and margins of permanent waters in April. Readily bites in
shaded areas during the day.
- Ochlerotatus atropalpus - Uncommon mosquito in Massachusetts, but can be a pest of
man as our data has shown. This species is known as the "rockpool" mosquito, which describes it's
preferred habitat, but data from New Jersey has shown that it has become
well adapted to artificial containers such used tire casings.
- Ochlerotatus aurifer - Found occasionally in the spring and early
summer. Vicious biting pest of humans and other mammals. Larvae are
found in the spring in open marshes.
- Ochlerotatus canadensis - Common late spring and summer mosquito.
Fierce biting pest of humans and other mammals. Larvae are abundant in
late spring and found occasionally during the summer in woodland pools,
swamp borders and grassy hummock areas. This long-lived mosquito is the
primary suspect in the transmission of heartworm to dogs and a possible
suspect in the transmission of EEE from birds to humans.
- Ochlerotatus cantator - A mosquito more common in salt marsh areas,
but has been collected in the Central Massachusetts
area. Larvae can be found in freshwater habitat that received runoff
from streets and highways that receive salt during the winter. Is
considered a pest of man, but not considered common in this area. when adult samples are found, it is likely that they
developed elsewhere.
- Ochlerotatus communis - Ochlerotatus communis
is a true snowpool species, common throughout
the northern United States
and Canada into Alaska. Throughout
its range, the species is associated with heavily forested areas at high
elevations. Ochlerotatus communis
larvae are most common in deep snowpools
filled with dark colored water in forested areas above elevations of
1500 ft. In most cases, Oc. communis is
the only large mosquito in the pools although in some years, small
numbers of another northern species, Ochlerotatus provocans,
may be intermixed.
- Ochlerotatus dorsalis - Ochlerotatus dorsalis
has distribution that extends over the greater portion of North American
northern Europe and into Asia. In the United States,
the mosquito reaches greatest abundance from the plains states to the
Pacific coast. In the east, it has been reported in lesser numbers
across the Great Lakes states to the east coast states of Massachusetts, Connecticut
and New Jersey.
Ochlerotatus dorsalis overwinters in
the egg stage and the eggs hatch after flooding during the first warm
weather in the spring. Oc. dorsalis is
well known for its capacity to migrate long distances. The adults are
strong fliers and have been traced for 22 miles in Utah
and more than 30 miles in California.
As a result, the mosquito has been recognized as a chance migrant in
some areas of its range. Ochlerotatus dorsalis
larvae occur in a variety of habitats including both brackish and
freshwater. They are found in large numbers on tidal marshes of the
Pacific coast. The species is also common along the margins of the Great
Salt Lake in Utah.
Ochlerotatus dorsalis can be found in a
variety of freshwater habitats including marshes, temporary pools formed
by precipitation, natural springs and irrigation water. The larvae Oc. dorsalis
have been found in association with numerous other mosquito species. In Utah, the species
has been found breeding with 18 other species of mosquitoes including Ochlerotatus
vexans, Culex tarsalis and Culiseta inornata . In New
York, under saline conditions, the larvae have
been found with Ochlerotatus sollicitans.
- Ochlerotatus excrucians - Very common mid spring and early summer
mosquito pest of humans and other mammals. Larvae are found in a wide
range of wetland habitats. This mosquito is a suspect in the
transmission of heartworm to dogs. Isolated specimens have been found throughout
the summer months.
- Ochlerotatus fitchii - Oc. fitchii is
a mosquito of the northern United States
and Southern portion of Canada.
Its range extends from Maine to New Jersey on the eastern seaboard, west to
northern Nevada and north into British Columbia.
Oc. fitchii is a univoltine
species with a typical northern Ochlerotatus life cycle. In Massachusetts,
the single generation of eggs hatch in April and the larvae reach 4th
instar during the early part of May. Egg hatch may be staggered during
the early season and a variety of instars can be collected from
different habitats in the same geographic area. Adults are on the wing
in May, blood feed and deposit their eggs which do not hatch until the
following spring. Oc. fitchii has been
reported from a wide variety of habitats but the species is most common
in semi-permanent bodies of water in open areas that support emergent
vegetation.
- Ochlerotatus grossbecki - Oc. grossbecki
is recognized as a mosquito of the southeastern United States, but the species is found
in Massachusetts
on occasion. The mosquito occurs at low levels throughout the more
southern areas of the state. Oc. grossbecki
is one of the earliest mosquitoes to hatch from overwintering eggs.
Development is rapid, considering the cold water that is present in the
early Spring. Oc. grossbecki
is on the wing before most mosquito control agencies put out their
surveillance traps, however, the species persists until early summer and
can be represented in low numbers in trap collections during May and
June. The larvae of Ae. grossbecki
are most common in flooded woodlands where mature Red Maple and Beech
are the dominant trees. Decomposing leaves add tannins to the aquatic
habitat and in most cases, habitat water is so
dark that a white dipper submerged more than 2 ft below the surface
cannot be clearly detected.
- Ochlerotatus japonicus japonicus - New species found in Mass. in 2000. This species was first
found in New York & New Jersey in 1998, then Connecticut in 1999. This mosquito is
native to Japan, Korea, Taiwan,
and southern China.
It's preferred habitat is artificial containers
and discarded tire casings. It is not believed at this time to be a
voracious biter of man, however research done by CMMCP has shown it can
be a pest. West Nile Virus has been isolated from this species.
- Ochlerotatus sollicitans - Very common summer mosquito found primarily
along the coast. This aggressive mosquito will bite on a hot sunny day
and is known to fly long distances, so it occasionally turns up in our
district. Larvae are found on the edges of salt marshes.
- Ochlerotatus stimulans - Spring mosquito that has been shown by data
collection to be found well into the summer months. Has a singe
generation like all spring mosquitoes, and is not considered a vector of
disease at this time. Readily bites mammals, and can be a common pest in
the spring.
- Ochlerotatus taeniorhynchus - The black salt marsh mosquito is a severe
biter of man and livestock along the southern coasts from North Carolina to Florida
and in the Caribbean. Unchecked
populations can have a major economic impact. While capable of
transmitting eastern equine encephalitis and St. Louis encephalitis in
the laboratory, it is not a major vector of these diseases in nature. It
is, however, an important natural vector of dog heartworm and Venezuelan
equine encephalitis. The black salt marsh mosquito is found on the
coastal plains from Massachusetts to Texas, in California
along the Pacific Coast and in the Caribbean.
It is more abundant in the south. This mosquito breeds in the upper
regions of grass salt marshes where it is generally associated with
spike grass (Distichlis spicata) and salt meadow hay (Spartina patens). In the south,
production also occurs in the high marsh associated with mangroves,
saltwort (Batis maritima)
and glassworts (Salicornia species). It
also breeds on dredge disposal islands along the Atlantic
Intracoastal Waterway. During the mosquito season, a
portion of each egg clutch will hatch when flooded. Productive salt
marsh sites are flooded at irregular intervals by wind or lunar tides,
or heavy rainfall. Bacteria and other microorganisms provide an abundant
food supply. in the field, hundreds to thousands of mature larvae often
form tightly clustered "balls" which are thought to be
associated with feeding, Under optimal conditions, emergence of adults
can occur in as little as six days following egg hatch. Host seeking
occurs in the evening and to a lesser extent in the morning. Females do
not seek hosts to any great extent during darkness. In daytime, hosts
that move near resting females may be attacked. The black salt marsh
mosquito will feed on birds as well as mammals. All populations in Florida exhibit
some autogeny which refers to an ability of
females to develop eggs without taking a bloodmeal. At northern latitudes,
eggs enter diapause in response to decreasing
day length and water temperature; breeding can occur year round in the
extreme south.
- Ochlerotatus triseriatus - Common summer mosquito. A pest of humans
and other mammals. Most of these larvae actually are found in old
rimless tires, although some are found in other shaded artificial
containers and in tree holes. When this mosquito is a pest, it's breeding source is usually close by. West Nile
Virus has been isolated from this species in 2000.
- Ochlerotatus trivittatus - Common summer mosquito. Larvae are found in
floodwater pools in both swamps and marshes. This pest is a persistent
biter, and will even bite during the day.
- Psorophora columbiae
- Psorophora
columbiae, formerly known as Ps. confinnis, is a widespread pest from Florida, where it is known as the 'glades
mosquito," to New York.
Scattered populations exist in Massachusetts
and across the United States
westward to California.
The species is found in Mexico,
Central America, the Caribbean and South America to Argentina.
Psorophora columbiae reaches its
greatest abundance in the rice growing areas of the southwestern U. S.
where astronomical numbers, similar in magnitude to the production of saltmarsh mosquitoes, may occur. Eggs are deposited
on moist soil which is subject to flooding by water from rainfall or
irrigation. The incubation period is about 3-5 days in the rice growing
areas of Arkansas.
The larvae mature rapidly during the hot summer, often developing from
first instar to pupae in as few as 3.5 days. The larvae develop in
temporary shallow freshwater pools and puddles where there is
vegetation. The larvae may occasionally be found in slightly brackish
water. Ideal sites for Production of larvae are ricefields,
grassy roadside ditches, and grassy swales. The normal flight range of
this mosquito is at least 6-8 miles; however, much longer distances have
been recorded. The mosquito is readily attracted to light, and the New Jersey light
trap is commonly used to monitor populations. The females are furious
biters in day or night. Hosts include any warm blooded animal; however
bovine blood seems to be preferred.
- Toxorhynchities rutilus septentrionalis - Predatory mosquitoes in the genus Toxorhynchites are the most common arthropods
which have been used for control of "container-breeding"
mosquitoes. The combination of carnivorous larvae and innocuous adults
is very attractive in biological control. Successful biological control
has been reported using Toxorhynchites
species from Japan,
Southeast Asia, the Caribbean and the United States. Most of the
71 species of Toxorhynchites are found
in forested tropical regions throughout the world. At least one, Toxorhynchites rutilus,
has a subspecies (septentrionalis) that
is found as far north as 40 degrees N latitude in Connecticut
and southern New York.
Limited collections have been made in the CMMCP area in Millbury and
Worcester. The other subspecies of Toxorhynchites
rutilus found in mainland United States, Tr. rutilus,
has been reported only from Florida, Georgia and Louisiana. Toxorhynchites
are unusually large mosquitoes; the wingspan may exceed 12 mm; the body
length may exceed 7 mm. Adults are frequently covered with iridescent
scales and the proboscis has a pronounced 90 degree downward curve.
Fourth instar larvae may be more than 2 cm in length. Adults feed on
plant nectars. A few species are precocious and do not need nectar to
initiate oviposition. Protein used in reproduction is apparently
entirely derived from larval feeding, although some nectars
may provide modest amounts of some amino acids. Cumbersome in flight,
they are most frequently seen resting near treeholes
or engaging in their characteristic elliptical oviposition flight
patterns at the mouth of natural and man-made containers. They are not
known to oviposit in small ponds or other open water such as ground
pools. Larvae feed on the living macroinvertebrates
inhabiting flooded treeholes, bromeliads and
man-made containers. They are dependent on movement for prey location.
Although they are more successful in feeding on mosquitoes, eating as
many as 400 larvae during their larval development periods, they can
successfully complete larval development with artificial protein sources
such as water fleas (Daphnia) or brine shrimp. Cannibalism is not
uncommon, especially in small containers, but containers such as tires
with ample food supplies may support half a dozen or more similarly
sized larvae. Larval behavior is especially intriguing with feeding
dependent on prey size and availability. Wanton killing of prey without
feeding has been reported. All known species are multivoltine. In the United States,
Toxorhynchites generally overwinter as
late larval instars. Diapause is controlled by
day length, rather than temperature. Although the use of Toxorhynchites alone is unlikely to reduce
pest or vector species below operational thresholds, they can be a
valuable tool in areas where containers and treeholes
contribute substantially to the standing crop of mosquitoes. However,
they are highly susceptible to insecticides, and care has to be
exercised in the timing of release of Toxorhynchites
and application of insecticide sprays. Their large size and docile
appearance create the opportunity for them to serve as focal points for
public awareness campaigns aimed at the cleanup of man-made containers
that are used as breeding sites by pest mosquitoes.
- Uranotaenia sapphirina - Uranotaenia sapphirina
is found from southeastern Canada
to Florida along the eastern seaboard
of the United States.
Its range extends into the central states west to North
Dakota and south into Mexico. Uranotaenia
sapphirina has a life cycle that is
similar to many of the Culex species. The adult females enter
hibernation after they have been inseminated in the fall, pass the
winter in a state of torpor and emerge in late spring to initiate a
multivoltine breeding season. The species lays unique egg rafts that
float partially submerged on the water's surface. Larvae are rarely
evident until July, but peak sharply during the month of August. Larvae
persist in prime breeding habitat into the month of September but
decline sharply with the onset of cool weather. The brightly ornamented
adults do not fly far from their breeding site but are readily attracted
to artificial light. Light traps that are placed near suitable breeding
habitat frequently give an overestimation of this species' population
density during the summer months. Uranotaenia sapphirina
is a mosquito that is almost always associated with permanent and semipermanent ponds that support rich stands of
emergent and floating vegetation. In many areas of Massachusetts, Duckweed (Lemna sp.) appears to be an indicator
plant. The larvae often congregate in large numbers among the tiny
leaves and trailing roots of this floating aquatic plant. Water depth
can vary from a few inches to several feet in the swampland utilized by
this species. Uranotaenia sapphirina
larvae usually avoid shade and are usually found in greatest abundance
in sunlit areas of the breeding habitat.
- Wyeomyis smithii - Wyeomyia
smithii belongs to the tribe Sabethini, a group of 12 mosquito genera that share
more biological than taxonomic characteristics. The tribe is well
represented in the New World tropics. Wyeomyia is the only sabethine
genus that occurs in North America. Wyeomyia smithii
has a distribution that extends from Newfoundland
south to Delaware, west to northern Illinois and northwest into Saskatchewan. The mosquito's distribution
corresponds to the range of the northern pitcher plant, Sarracenia purpurea
gibbosa. Another pitcher plant mosquito, Wyeomyia haynei,
is found in the southern pitcher plant, Sarracenia
purpurea venosa,
from Maryland to South Carolina. The range of the two
pitcher plant mosquitoes does not appear to overlap. Wyeomyia
smithii is a multivoltine mosquito that
completes its entire life cycle in the immediate vicinity of its
predacious host plant. The females deposit their eggs directly on the
water within the plant or just above the waterline in older leaves. The
larvae live in the liquid of the plant and feed on the carcasses of
insects and spiders being digested by the plant enzymes. Multiple
generations take place from spring through fall. Late in the season, the
females attach eggs to young leaves, before they become filled with
water. The species overwinters as a larva frozen in a block of ice
within the plant. The overwintering larvae pupate during the month of
May and are usually on the wing by June. Wyeomyia
smithii is an obligate inhabitant of the
predacious pitcher plant and has never been reported from any other
larval habitat.
Additional
species descriptions will be added in the near future. Please check back
soon.
Credit must
be given for the information complied here to Dave Henley at the East
Middlesex Mosquito Control Project, Dr. Wayne Crans at Rutgers University,
Tim Deschamps and Curtis Best at the Central Massachusetts Mosquito Control
Project, as well as the Massachusetts Entomologist group.
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