Culicinae
   HOME

TheInfoList



OR:

The Culicinae are the most extensive subfamily of
mosquito Mosquitoes, the Culicidae, are a Family (biology), family of small Diptera, flies consisting of 3,600 species. The word ''mosquito'' (formed by ''Musca (fly), mosca'' and diminutive ''-ito'') is Spanish and Portuguese for ''little fly''. Mos ...
es (Culicidae) and have
species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...
in every continent except Antarctica, but are highly concentrated in tropical areas. Mosquitoes are best known as parasites to many
vertebrate Vertebrates () are animals with a vertebral column (backbone or spine), and a cranium, or skull. The vertebral column surrounds and protects the spinal cord, while the cranium protects the brain. The vertebrates make up the subphylum Vertebra ...
animals and vectors for
disease A disease is a particular abnormal condition that adversely affects the structure or function (biology), function of all or part of an organism and is not immediately due to any external injury. Diseases are often known to be medical condi ...
. They are holometabolous
insects Insects (from Latin ') are hexapod invertebrates of the class Insecta. They are the largest group within the arthropod phylum. Insects have a chitinous exoskeleton, a three-part body (head, thorax and abdomen), three pairs of jointed ...
, and most species lay their eggs in stagnant water, to benefit their aquatic larval stage.


Introduction

The
subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...
Culicinae is the largest subfamily of
Culicidae Mosquitoes, the Culicidae, are a Family (biology), family of small Diptera, flies consisting of 3,600 species. The word ''mosquito'' (formed by ''Musca (fly), mosca'' and diminutive ''-ito'') is Spanish and Portuguese for ''little fly''. Mos ...
, a
family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...
of
Nematocera The Nematocera (the name meaning "thread-horns") are a suborder of elongated fly, flies with thin, segmented antenna (biology), antennae and mostly aquatic larvae. This group is paraphyletic and contains all flies except for species from suborder ...
dipterans. There are 3,046 species of Culicinae mosquitoes, in 108
genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...
and 11 tribes. Members of the Culicinae subfamily are small flies with fore wings for flight and hind wings reduced to halteres for balance. The mosquitoes also have long, slender, legs and
proboscis A proboscis () is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular arthropod mouthparts, mouthparts used for feeding and sucking. In vertebrates, a pr ...
-style mouth parts for feeding on vertebrate blood or plant fluids. Only the females are blood feeders, requiring a high quality protein meal before they can oviposit. Because the mosquitoes are well adapted for finding hosts, the females can move quickly from one blood meal to another, and when injecting their saliva, can inject pathogens picked up from other hosts and thus efficiently spread disease.


Lifecycle

Culicinae mosquitoes are holometabolous, going through four distinct life stages: egg,
larva A larva (; : larvae ) is a distinct juvenile form many animals undergo before metamorphosis into their next life stage. Animals with indirect development such as insects, some arachnids, amphibians, or cnidarians typically have a larval phase ...
, pupa, and adult. The duration of each stage is species-specific, but all Culicinae mosquitoes are multivoltine. The egg, larval, and pupal stages are aquatic. Adults leave the water by flight to find plants or vertebrates on which to feed.
Oviposition The ovipositor is a tube-like organ used by some animals, especially insects, for the laying of eggs. In insects, an ovipositor consists of a maximum of three pairs of appendages. The details and morphology of the ovipositor vary, but typica ...
can occur in natural reservoirs of salt water or
fresh water Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salt (chemistry), salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include ...
, or temporary pools, but oviposition sites are generally stagnant. All '' Psorophora'' and some ''
Aedes ''Aedes'' (also known as the tiger mosquito) is a genus of mosquitoes originally found in tropical and subtropical zones, but now found on all continents except Antarctica. Some species have been spread by human activity: ''Aedes albopictus'', ...
'' species oviposit on soil where the eggs remain, unhatched, till flooded. Many species associate closely with humans, using accumulated ground water in developed areas for oviposition. Some species use plant cavities for oviposition. These species can, as larvae, drill into the plant for air.


Eggs

Culicinae eggs are laid in groups by adult females, often numbering over a hundred. Most species lay the eggs on the surface of stagnant water. The female lays the eggs vertically and side by side, held together by a sticky substance excreted to coat the eggs, head end down, creating an egg raft that is convex below and concave above with ends that are typically upturned. Species that use this form of egg-laying typically hatch as first
instar An instar (, from the Latin '' īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the exoskeleton in order to ...
larvae within a few hours of laying. Oviposition on the surface of stagnant water is most common, but some species of ''Aedes'' and all ''Psorophora'' deposit their eggs in areas that will flood. Eggs are laid and embryological development occurs, but the eggs do not hatch till flooded. After flooding, the eggs will hatch within two to three days.


Larvae

Culicinae larvae are adapted to almost every aquatic environment worldwide, excepting flowing streams and open areas of large water masses. Larvae have three body regions –
head A head is the part of an organism which usually includes the ears, brain, forehead, cheeks, chin, eyes, nose, and mouth, each of which aid in various sensory functions such as sight, hearing, smell, and taste. Some very simple ani ...
,
thorax The thorax (: thoraces or thoraxes) or chest is a part of the anatomy of mammals and other tetrapod animals located between the neck and the abdomen. In insects, crustaceans, and the extinct trilobites, the thorax is one of the three main di ...
, and
abdomen The abdomen (colloquially called the gut, belly, tummy, midriff, tucky, or stomach) is the front part of the torso between the thorax (chest) and pelvis in humans and in other vertebrates. The area occupied by the abdomen is called the abdominal ...
– as well as having compound eyes and antennae on their heads. The same body regions can be found in Culicinae adults, but the form of each region is very different in the larvae and adults. The larvae have four
instars An instar (, from the Latin ''wikt:instar#Latin, īnstar'' 'form, likeness') is a developmental stage of arthropods, such as insects, which occurs between each ecdysis, moult (''ecdysis'') until sexual maturity is reached. Arthropods must shed the ...
from hatching to pupation that occur over four days to two weeks. Culicinae larvae can be distinguished from larvae of other subfamilies by the presence of the posterior siphon. The siphon is used for breathing and breaks the water surface, so the larvae can take in air. Most species hang from the surface of the water, anterior end down, so the siphon stays at the water surface. Some species of '' Mansonia'' and '' Coquillettidia'' use the siphon differently, piercing underwater
plants Plants are the eukaryotes that form the kingdom Plantae; they are predominantly photosynthetic. This means that they obtain their energy from sunlight, using chloroplasts derived from endosymbiosis with cyanobacteria to produce sugars f ...
to take
oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...
. Larvae eat small aquatic organisms and plant material in the water using brush-style and grinding mouth parts. A few species are
predator Predation is a biological interaction in which one organism, the predator, kills and eats another organism, its prey. It is one of a family of common List of feeding behaviours, feeding behaviours that includes parasitism and micropredation ...
y and have additional mouth parts for grasping. Larvae use jerks of their bodies for locomotion, combined with
propulsion Propulsion is the generation of force by any combination of pushing or pulling to modify the translational motion of an object, which is typically a rigid body (or an articulated rigid body) but may also concern a fluid. The term is derived from ...
using the mouth bristles. They are sensitive to the conditions of the water in which they live, including light, temperature, and many other factors, and are also subject to predation and depend on aquatic vegetation to hide from predators.


Pupae

Culicinae pupae are aquatic and do not feed, but they do require air intake. All pupae must come to the water surface for air, with the exception of '' Mansonia'' and '' Coquillettidia'' species. Pupae are exarate, allowing movement of the exposed abdomen. Thrashing of the abdomen can move the pupae quickly, sideways or downward, but as soon as movement of the abdomen stops, the pupae return to the surface of the water. The pupa naturally rises to the surface of the water due to an air pocket between the wing cases that make it lighter than water. Pupation lasts as little as one day to as much as several weeks, because some diapause can occur.


Adults

Adult mosquitoes are about equal in proportions of males and females, but males emerge from the pupal stage before females. Males stay near the breeding ground and mate soon after the females emerge. Females only need to mate once, then store sperm to use over their lifetimes. After mating, adults leave the breeding ground and can fly great distances. Culicinae adults inhabit almost every environment, and both males and females feed on plant sugars. Females also feed on animal blood, which most species need before they can lay eggs. After a blood meal, females take two or more days to digest the blood before oviposition. After egglaying, females begin searching for another host for a blood meal. Different species of mosquitoes have preferences to blood meals from specific species of hosts, but can feed on other species. Adults have three body regions, with narrow membranes joining the segments, and are two to 15 mm in length. The first body region, the head, holds the large compound eyes,
proboscis A proboscis () is an elongated appendage from the head of an animal, either a vertebrate or an invertebrate. In invertebrates, the term usually refers to tubular arthropod mouthparts, mouthparts used for feeding and sucking. In vertebrates, a pr ...
-style mouth parts, and plumose antennae. The antennae of males are more plumose than those of females, to catch pheromones to find a mate. The thorax is covered in scales and setae helpful in species identification. Attached to the thorax are three pairs of long, slender legs, a pair of fore wings used for flight, and hind wings reduced to halteres for balance. The abdomen is slender, but membranous so it can swell when feeding. The abdomen has 10 segments, but only eight are visible. The last two segments are reduced and used for
reproduction Reproduction (or procreation or breeding) is the biological process by which new individual organisms – "offspring" – are produced from their "parent" or parents. There are two forms of reproduction: Asexual reproduction, asexual and Sexual ...
. The lifespan of adult Culicinae can vary greatly based on environment, predation, and
pest control Pest control is the regulation or management of a species defined as a pest (organism), pest; such as any animal, plant or fungus that impacts adversely on human activities or environment. The human response depends on the importance of the da ...
.


Feeding

Culicinae adults of both sexes feed on plant sugars, such as
nectar Nectar is a viscous, sugar-rich liquid produced by Plant, plants in glands called nectaries, either within the flowers with which it attracts pollination, pollinating animals, or by extrafloral nectaries, which provide a nutrient source to an ...
. Feeding on blood is only practiced by females, to gain a high-
protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residue (biochemistry), residues. Proteins perform a vast array of functions within organisms, including Enzyme catalysis, catalysing metab ...
meal for egg production. The mouth parts of females are adapted for piercing the skin of hosts, whereas the similar mouth parts of males are incapable of piercing skin. When feeding on blood, females use their large compound eyes to initially find a host. When near a host, females can detect changes in light and odors. They can then land and use their probosces to feel for a place to bite. To feed, they pierce the skin and inject saliva containing an
anticoagulant An anticoagulant, commonly known as a blood thinner, is a chemical substance that prevents or reduces the coagulation of blood, prolonging the clotting time. Some occur naturally in blood-eating animals, such as leeches and mosquitoes, which ...
and an anesthetic. The anesthetic reduces pain so the host does not detect the bite, and the anticoagulant prevents blood from clotting so they can continue to feed. Pathogenic organisms contained in the saliva injection by the female mosquitoes can quickly spread diseases.


Taxonomy

The subfamily Culicinae has 3,046 species in 108 genera that are sorted into 11 tribes. The tribes and genera they contain are shown below, with the number of species in each genus noted. ;Aedeomyiini; * '' Aedomyia'' (7 species)


Aedini


Culicini

* '' Culex'' (844) * '' Deinocerites'' (18) * '' Galindomyia'' (1) * '' Lutzia'' (8) ;Culisetini * '' Culiseta'' (37)


Ficalbiini

# '' Ficalbia'' (8) # '' Mimomyia'' (45) ;Hodgesiini * '' Hodgesia'' (11)


Mansoniini

# '' Coquillettidia'' (57) # '' Mansonia'' (25) ;Orthopodomyiini * '' Orthopodomyia'' (35)


Sabethini

;Toxorhynchitini * '' Toxorhynchites'' (88) ;Uranotaeniini * '' Uranotaenia'' (267)


References

* * Bay, D.E.; Harris, R.L. (1988). ''Introduction to Veterinary Entomology: A Guide to Livestock Insects:'' 43–51. Robert Harris Publisher. {{Authority control Nematocera subfamilies