Aedes taeniorhynchus (Syn.: Ochlerotatus taeniorhynchus), auf Deutsch auch Schwarze Salzwiesenmücke (engl. Black Salt Marsh Mosquito) genannt, ist eine in Amerika beheimatete Stechmückenart. Innerhalb der Sammelgattung Aedes gehört diese Art zur Untergattung Ochlerotatus.[1]
Aedes taeniorhynchus kommt auf Salzwasserwiesen der Küstenebenen von Massachusetts bis Texas vor. Sie leben ebenfalls auf den Inseln des Atlantic Intracoastal Waterways.[2] Ein weiteres Verbreitungsgebiet ist Mittelamerika und der karibische Raum bis an die Atlantikküste Kolumbiens und Venezuelas. Feuchtwarmes Tropenklima begünstigt die Ausbreitung von Aedes taeniorhynchus.[2]
Adulte Exemplare der Schwarzen Salzwiesenmücke sind dunkelfarben. Der Rücken ist schwarz und die Seiten sowie die Abdominalsegmente besitzen weiße Streifen.[2]
Aedes taeniorhynchus gehört innerhalb der Gattung Aedes zur Untergattung Ochlerotatus. Ochlerotatus wurde im Jahr 2000 von John F. Reinert als eigene Gattung aus der Gattung Aedes herausgelöst,[3] aber 2015 von anderen Autoren wieder mit dieser vereinigt. Die Gruppe der Stechmücken, die zuvor der Gattung Ochlerotatus angehört hatten, wird nun wieder in die Untergattung Ochlerotatus gestellt. Daher ist für die Schwarze Salzwiesenmücke auch der Name Aedes (Ochlerotatus) taeniorhynchus geläufig.[1][4]
Aedes taeniorhynchus lebt häufig in Gemeinschaft und im selben Habitat zusammen mit der Östlichen Salzwiesenmücke (Aedes sollicitans). Die Art tritt auch zusammen mit Anopheles bradleyi, Anopheles crucians und Anopheles atropos auf.[2] Diese Stechmückenart bewohnt die unteren Regionen der Salzwassermarschwiesen, wo Distichlis spicata und Spartina patens vorkommen. Im südlichen Verbreitungsgebiet findet man die Mücken in den Mangrovensümpfen, und an Wuchsorten von Salicornia und des Kreuzblütlers Batis maritima. O. taeniorhynchus. Die Weibchen sind in der Lage 100 bis 200 Eier entlang der Wasserlinie in Senken, regenwasserbestandenen Niederungen, Salzwassermarschen oder Mangrovensümpfen abzulegen. Die Entwicklung der Mücken wird vom unregelmäßigen Wasserstand sowie von Wind und Tide beeinflusst. Obwohl die Art im Salzwasserlebensraum lebt, ist ihre Entwicklung vom Süßwasser abhängig.[5] Unter günstigen Umweltbedingungen schlüpfen die Insekten nach sechs Tagen. Die Tiere sind bereits zwei Tage nach dem Schlüpfen geschlechtsreif und bilden in der Dämmerung Schwärme über Bäumen und Sträuchern. Der Lebenszyklus dieser Stechmückenart wird von Regen- und Trockenzeiten bestimmt. Aedes taeniorhynchus hat ein enormes Reproduktionspotential. Ein Weibchen legt in der Regel in seiner Lebenszeit 100 Eier ab, davon schlüpfen etwa 50 % weibliche Tiere. Geht man davon aus, dass die daraus schlüpfenden Weibchen wiederum 100 Eier ablegen, dann entstehen daraus bereits 5000 Mosquitos. Es ist somit möglich, dass innerhalb von nur zwei Generationen 250.000 Stechmücken entstehen.[6] Wanderbewegungen von Aedes taeniorhynchus sind mit Windgeschwindigkeit, Windrichtung, Landschaftstopographie und dem Vorkommen von Blütennektar korreliert. Es wurde gemessen, dass Weibchen zwei bis fünf Meilen weit fliegen können, mit unterstützendem Wind können auch 30 Meilen und mehr erreicht werden.[2]
Für die Eiablage benötigen die Weibchen Blut. Im Tageslicht verbergen sich die Tiere meist in dichter Vegetation. Sie beginnen mit der aktiven Nahrungssuche in der Abenddämmerung und beenden diese im Morgengrauen. Während des Tages kommt es zu Stichen meist nur, wenn sich Menschen in unmittelbarer Nähe der Weibchen aufhalten.[2] In anderen Zonen kann es zu jeder Tageszeit zu Stichen kommen.[6] Gestochen werden Vögel und Säugetiere.[2] In den Populationen der Stechmücke in Florida wurde ein gewisser Grad an „Autogenie“ beobachtet, d. h. Weibchen sind dort in der Lage auch ohne Blutaufnahme Eier zu bilden. In nördlichen Breitengraden ihres Verbreitungsgebietes können die Eier abhängig von Tageslänge und Wassertemperatur in eine Diapause treten. Im Süden erfolgt der Reproduktionszyklus hingegen das ganze Jahr.[2]
Die Weibchen von Aedes taeniorhynchus sind zu bestimmten Tageszeiten für ihr penetrantes Stechverhalten bekannt und gelten bei Menschen und Nutztieren von North Carolina bis Florida und im Karibischen Raum als Schadinsekten. Unkontrollierte Mückenpopulationen können zur Plage werden, wenn sie in sehr großen Schwärmen auftreten. Sie haben gute Flugeigenschaften und können in Massen in bewohnten Gebieten auftreten.[6] Aedes taeniorhynchus wurde als Überträger bestimmter Krankheiten wie Enzephalitis, EEE-Virus (Eastern Equine Encephalomyelitis Virus),[7] Dirofilaria immitis und anderen identifiziert. 1989 nach dem Hurrikan Hugo wurde Aedes taeniorhynchus zur dominierenden Stechmückenspezies in der Karibik.[6]
Die Entwicklung der Larven der Schwarzen Salzwiesenmücke wurde ursprünglich durch das Ausbringen von Mineralöl auf die Wasseroberfläche bekämpft. In einigen Gegenden der USA (z. B. Louisiana) werden großflächig Insektizide appliziert. Mittlerweile sind einige natürliche Antagonisten wie Bacillus thuringiensis, Nematoden und einige Pilzarten identifiziert, die zu einer biologischen Kontrolle der Stechmücken verwendet werden können.[8][9]
Aedes taeniorhynchus (Syn.: Ochlerotatus taeniorhynchus), auf Deutsch auch Schwarze Salzwiesenmücke (engl. Black Salt Marsh Mosquito) genannt, ist eine in Amerika beheimatete Stechmückenart. Innerhalb der Sammelgattung Aedes gehört diese Art zur Untergattung Ochlerotatus.
Aedes taeniorhynchus, or the black salt marsh mosquito, is a mosquito in the family Culicidae. It is a carrier for encephalitic viruses including Venezuelan equine encephalitis[3] and can transmit Dirofilaria immitis.[4] It resides in the Americas and is known to bite mammals, reptiles, and birds. Like other mosquitoes, Ae. taeniorhynchus adults survive on a combination diet of blood and sugar, with females generally requiring a blood meal before laying eggs.[5]
This mosquito has been studied to investigate its development, physiological markers, and behavioral patterns, including periodic cycles for biting, flight, and swarming. This species is noted for developing in periodic cycles, with high sensitivity to light and flight patterns that result in specific wingbeat frequencies that allow for both species detection and sex distinction.[6][7]
Ae. taeniorhynchus is known to be a pest to humans and mechanisms for controlling Ae. taeniorhynchus populations have been developed. The United States has spent millions of dollars to control and contain Ae. taeniorhynchus.[8]
German entomologist Christian Rudolph Wilhelm Wiedemann described Ae. (Ochlerotatus) taeniorhynchus in 1821. Alternate namings for the species include Culex taeniorhynchus (Wiedemann, 1821), Ochlerotatus taeniorhynchus (Wiedemann, 1821), and Culex damnosus (Say 1823).[9][10]
Aedes niger, also known as Aedes portoricensis, is a subspecies of Ae. taeniorhynchus.[11] It can be identified by its last posterior tarsal joint, which is mostly black rather than banded in white.[11] It resides in Florida and can migrate as far as 95 mi (153 km).[11]
Analysis of microsatellite data on the genes of Ae. taeniorhynchus living in the Galapagos Islands show genetic differentiation between coastal and highland mosquito populations.[12] Data indicates minimal gene flow between the populations that only occurs during periods of heightened rainfall.[12] Genetic differences suggest that habitat differences led to driving adaptation and divergence in the species, eventually leading to future speciation.[12] Highland mosquitoes have population features characteristic of a founder effect due to low genetic diversity manifesting as low heterozygosity and low allelic richness, which may have resulted from egg dormancy during periods of dryness.[12]
Ae. taeniorhynchus adults are mostly black with areas of white banding. A single white band appears at the center of the proboscis, multiple white bands span the distal ends of the legs following the leg joints, and the last hind leg joints are completely colored white.[11] Ae. taeniorhynchus wings are long and narrow with scaled wing veins.[13] Experimental investigation of evolutionary coloration of Ae. taeniorhynchus yielded negative results.[14] Mosquitoes reared in conditions of darkness, backgrounds colored black, white, or green, and lighting conditions of fluorescent light or sunlight, showed no color changes in the fat body nor in the head capsule, saddle, or siphon.[14] This lack of cryptic coloring is suggested to be due to a lack of threat to the species; because the species habitat is a temporary water source used for larval growth, this temporary environment has few predators and relatively little danger.[14]
Males and females can be distinguished based on their antennae: males have plumose (feather-like) antennae while females antennae are sparsely haired.[13]
Ae. taeniorhynchus swarms can be detected through sound. Noises with frequencies between 0.3 and 3.4 kHz at sound level 21 dB are detectable across 10–50 m in distance. An individual mosquito can be heard across 2–5 cm in distance when sound level rises to 22-25 dB.[7] Male and female mosquitoes can also be distinguished by their wingbeat frequencies, which are 700–800 Hz for males and 400–500 Hz for females.[7] As a result, flight sounds are used to determine flight activity and distinguish sex of groups.
Aedes mosquitoes have a characteristic microbiome that modulate the effects of diet.[15] Microbiome makeup is reported to differ between males and females in Aedes mosquitoes, such as Aedes albopictus[16] and Aedes aegypti.[17] Namely, in Aedes albopictus, males feed on nectar to acquire Actinomycetota while females contain Pseudomonadota (such as Enterobacteriaceae) that mediate levels of redox stress caused by feeding on blood-meals.[16]
The main physical distinctions between Ae. taeniorhynchus and other species come from the white banding that covers several body parts along Ae. taeniorhynchus. The species, like other Aedes mosquitoes, exhibits basal banding of the abdomen, but Ae. taeniorhynchus also uniquely exhibits white-tipped palps and a central white ring on the proboscis.[13]
This species looks similar to Aedes sollicitans, except for subtle differences in the larval and adult stages. In the larval stage, Ae. taeniorhynchus has a shorter breathing tube, its scale patches are rounded instead of pointed at the tips, and spines that line the edges of each scale patch are smaller near the scale patch base.[11] In the adult stage, Ae. taeniorhynchus is smaller and mostly black while Ae. sollicitans is golden brown.[11]
The species also bears similarity to Aedes jacobinae, which falls within the Taeniorhynchus subgenus due to its particular hypopygium structure, but it is considered a distinct species because it does not have leg markings.[18] Similarly, this species can also be distinguished from Aedes albopictus, commonly known as the Asian Tiger Mosquito, as Ae. taeniorhynchus, unlike Ae. albopictus, does not have markings on its back.[19]
Ae. taeniorhynchus is widely distributed across North and South America, though more highly concentrated in southern regions.[20][21] At the time of the fly's initial discovery the species resided in coastal regions, and then gradually moved towards the interior of the Americas.[18] Gene flow analysis derived from microsatellite data indicated that mosquitoes located in the Galapagos Island in the Pacific Island frequently migrate between islands on an isolation by distance basis.[22] Incidence of ports was a strong factor contributing to migration, suggesting human-aided transport contributed to inter-island migration.[22]
Ae. taeniorhynchus resides in habitats with a temporary water source, making mangrove and salt marshes or other areas with moist soil popular locations for egg laying and immature growth.[23] These habitats are highly variable but often have high salinity with an observed soluble salt content in soil of at least 1644 ppm.[24]
In the case of environmental conditions of dryness and low temperatures which are unfavorable for egg hatching, eggs can remain dormant for years.[25] Factors controlling the scale of A. taeniorhynchus growth during pre-emergence depend on environmental conditions matching moisture level and temperature. In Southern Florida, the main factors are tide height and amount of rainfall,[26] while sites in California rely on tide height alone.[27] In Virginia, these factors are limited to levels of rainfall and temperature.[28] Generally favorable factors can turn negative at extreme values, causing survival rate to decline. Excess water washes mosquito eggs away[26] and extremely high temperatures can lead to water source evaporation.[27]
This species exhibits sensitivity to temperature, with differences found for constant, split, and alternating temperatures.[29] At constant temperatures of 22, 27, and 32 °C, life span increased with temperature, but at split temperatures, mosquitoes were also split between life and death.[29] At different temperatures, the rate of aging was independent in males, but higher for females living at 22 and 27 °C.[29] At alternating temperatures, life spans were temperature independent for all sexes and temperatures, except for favoring of alternation between 22 and 27 °C by females.[29]
Breeding locations for Ae. taeniorhynchus are often in contact with vegetation such as Distichlis spicata (spike grass) and Spartina patens (salt meadow hay) in grass salt marshes and Batis maritima (saltwort) and species from the Salicornia genus (glassworts) in mangroves.[21] This species of mosquito is found in close proximity to other mosquitoes that reside in marches. These include Aedes sollicitans (eastern salt marsh mosquito), Anopheles bradleyi, and A. atropos.[21]
According to observational field studies, Ae. taeniorhynchus carries out several behavioral trends at different stages of life. Growth and pupation of this species were found to be affected by environmental factors of nutrition, population density, salinity, light-dark, and temperature.[30]
Females lay eggs on dry ground, and egg hatching is triggered by the presence of water, such as rain or flooding.[31] Egg laying yield from females, an indicator of fecundity, differs based on diet: in populations of low autogeny, rare autogenous females each laid less than 30 eggs, while egg yield was significantly higher in populations with majority autogenous females.[25] Eggs laid in the right temperature and humidity conditions undergo embryogenesis, then stay dormant until hatching.[30]
Upon hatching, the species progresses through 4 larval instars: the first 3 instars are affected primarily by temperature, with minor effects by salinity; the fourth instar is affected by all environmental factors.[30] In the fourth instar, increased food sped up development time while crowding and salinity stunted growth.[30]
Preferred temperature for all 4 instars is between 30 °C and 38 °C but average preferred temperature increases with age.[32] The first instar prefers an average temperature of 31.8 °C and the early fourth instar prefers a temperature of 34.6°.[32] The late fourth instar, however, has a lower preferred temperature than the early fourth instar, at 33.0°.[32] Starved larvae were found to have a wider preferred temperature range that is centered around lower temperatures.[32] Laboratory larval colonies cultured for years 27.0 °C were found to prefer consistently lower temperatures.[32]
Fourth-instar larvae were noted to drink sea water (100 nL/h) and secrete hyperosmotic fluid through the rectum.[33] This fluid is similar to seawater but with 18-fold higher potassium levels.[33] Because the secreted fluid does not allow for osmotic balance with the ingested fluid, studies suggest that the anal papillae aid in salt secretion.[33]
All environmental factors affect pupation regarding the insect's diurnal rhythm, which has a period of 21.5 hours.[30] Factors leading to an increased pupa period include erase of light-dark cycles with all dark or all light conditions, increased salinity, and crowding. These trends continued to adhere to a preference for temperatures close to 27 °C or 32 °C.[30] Pupa also exhibit differential aggregation formation due to these environmental factors. Cluster type aggregations form alongside temporary crowding and excess of food while ball type aggregations may manifest out of temporary crowding but lack of food.[34] At lower constant temperatures of 22 °C and 25 °C, cluster type aggregations may form but higher temperatures of 30° and 32 °C inhibit aggregation formation.[34] Aggregations produced pupa with slightly heavier dry body weights and promoted developmental synchronization in ecdysis and greater likelihood of migration at emergence.[34]
Males and females mosquitoes emerge from their egg sites in similar ways. They remain in their sources of water for 12–24 hours.[23] Adults then migrate away from the egg laying ground over the course of 1–4 days.[8] Different sexes exhibit differential migration, with most females traveling at least 20 mi (32 km), and most males traveling no farther than 2 mi (3.2 km).[8] Female migration follows a random pattern with no limitation on migration direction and migration occurring along a 5-day cycle.[8] Males initially travel with females until they hit a 1–2 mi (1.6–3.2 km) stopping point, where they replace migration with swarming.[8]
Flight patterns become established in the adult stage and are not affected by behavioral patterns from earlier stages of life.[6] Adults begin biting at day 4 and follow a 5-day cycle until death. Between the sexes, peak biting intensity occurs in females at ages 4, 9, and 14 days.[23] Adult female mosquitoes continue living and laying eggs for 3–4 weeks before dying.[23] Those that survive longer continue to bite but stop laying eggs.[23]
Ae. taeniorhynchus eggs can mature both autogenously and anautogenously, with autogenous eggs feeding on sugar and anautogenous eggs requiring a blood meal.[35] These food sources promote maturation by producing hormones from the corpora allata (CA) and medial neurosecretory cell perikarya (MNCA), of which only MNCA hormone release is responsible for anautogenous maturation.[35] Larval dependence on a blood meal can be influenced to make mosquitoes less autogenous, by not allowing females to feed on sugar and imposing other dietary changes.[36]
Adult mosquitoes feed on a combination diet of blood and sugar, with the optimal diet consisting of sugar for males and both blood and sugar for females.[5] Most Ae. taeniorhynchus rely on mammals and birds for blood meals, especially depending on bovine, rabbits, and armadillos.[37] Mosquitoes in the Galapagos Islands feed on mammals and reptiles, with equal preference but feed little on birds.[38] Since this differs from the typical feeding of Ae. taeniorhynchus on birds, studies suggest the species is an opportunistic feeder, in which it feeds more on the most readily available, easily accessible organisms.[38] Ae. taeniorhynchus acts as an ectoparasite to Diomedea irrorata, known as waved albatrosses.[39] Mosquitoes bite the waved albatrosses, directly leading to or transmitting diseases that cause nestling mortality, colony migration, or egg desertion in albatrosses.[39]
Experimental studies show that both sexes can survive on a sugar-only diet for 2–3 months, but females require blood meals for egg production.[40] In females, supplementation of a blood meal in autogenous mosquitoes increased both egg production and lifespan.[40] Additional observational studies of Ae. taeniorhynchus in nature showed that habitat impacts the effect of the meal source: females inhabiting mangrove swamps could produce eggs even without blood meals, but those from a grassy salt marsh environment could not.[41] Females from both habitats, however, were still able to produce eggs when given blood meals.[41]
Studies observing unrestricted sugar intake of females correlated sucrose intake level with maximum accumulation of stored energy reserves.[42] In contrast, sucrose intake level does not correlate with decreased activity or changes in senescence.[42]
Carbohydrate feedings of female mosquitoes in a laboratory setting indicated that carbohydrates glucose, fructose, mannose, galactose, sucrose, trehalose, melibiose, maltose, raffinose, melizitose, dextrin, mannitol, and sorbitol are most effective to aid survival; arabinose, rhamnose, fucose, sorbose, lactose, cellobiose, inulin, a-methyl mannoside, dulcitol, and inositol are not used by the species; xylose, glycogen, a-methyl glucoside, and glycerol are used but at a slow metabolic rate; and sorbose could not be metabolized.[43] Feeding with glucose allowed for maximum flight speed while other carbohydrates, such as all pentoses, sorbose, lactose, cellobiose, glycogen, inulin, a-methyl mannoside, dulcitol, and inositol were insufficient to allow flight, indicated by a delay in flight after feeding.[29]
If emergence occurs at a location with flowers, both sexes feed on nectar prior to migration.[44] Analysis of fructose and glycogen content indicate that mosquitoes often feed on nectar soon after dark and feed sparingly on nectar during the day.[45]
Males become sexually mature about 2 days after emergence, and females become sexually mature at an age of 12 days, with plans to mate only once.[21]
Observational studies of mating interactions both in a laboratory setting and field setting noted copulation between mosquitoes occurring after sunset. Results noted that copulation depends on age of females, with insemination occurring with females of ages 30–40 hours.[46] In both settings studied, females are capable of mating without inducing insemination, as only 1% of females contained sperm after 2 notes of potential mating.[46] Mating not only provides an opportunity for insemination but also contributes to vitellogenin synthesis in females, as experimental injections of male accessory gland fluid (MAGF) has been shown to cause release of corpus cardiacum (CC) stimulating factor in the ovaries, which spurs research of egg development neurosecretory hormone (EDNH).[47]
Other laboratory studies of the species noted an age dependence in both females and males for successful copulation and insemination.[48] Copulation is initiated by males and only occurs when the male first disengages its legs, interlocks the male and female genitalia in an end-to-end position, and then hangs from the female for a short duration of time.[48] Insemination can only result from copulation.[48] If copulation is successful, the mosquitoes pair in flight, then land and remain together for a few seconds.[48] To end copulation, the male flies away or the female flies while carrying the male until it falls.[48]
Most young females rejected copulation attempts (unreceptive), and many of those that copulated rejected insemination attempts (refractory), with acceptance of copulation and insemination (receptive) both increasing with female age when exposed to an older male cohort.[48] Unreceptive females avoided males by flying away with sudden increases in speed or sharp turns.[48]
During mating, males can transfer substances produced from their accessory glands that affect female physiology and behavior.[49] These accessory gland substances can limit or improve female reproductive activities.[49] Limitations include temporarily prevention of future female mating, oviposition stimulation, and reduced host-seeking while improvements involve changes to female circadian rhythm and metabolic priorities that cause higher chance of reproduction.[49]
Females are known to practice oviposition, with preference for high moisture soils, with water saturation greater than 70%.[50] Female clutch sizes are 100-200 eggs, with at least one clutch laid per female.[21]
In experimental studies with ovariectomized female mosquitoes, females were unable to synthesize vitellogenin, a yolk-protein precursor, unless given a donor ovary from a sugar-fed or blood-fed mosquito.[51] Vitellogenin synthesis still occurred when the donor ovary came from Ae. aegypti, and ovary derivation from a blood-fed mosquito caused corpus cardiacum stimulating factor production, indicating that the hormonal processes for oviposition are not species specific.[51]
In a study of eggs laid in Rhizophora mangle L. (red mangrove) and Avicennia germinans L. (black mangrove) forest basins, egg occurrence was correlated with elevation and detritus level.[52] Oviposition was directed from black mangrove basins to red mangrove basins, possibly due to reduced detritus and reduced organic content in the soil caused by black mangrove grazing by Melampus coffeus L., a snail.[52] Because eggshells and eggs share the same habitat, it is suggested that oviposition may be delineated using eggshells.[52] Eggshell sampling analysis from 34 mangrove forest sites indicated that all mangrove basin forests can yield successful Ae. taeniorhynchus production, regardless of forest geomorphology, soil, and vegetation but recently flooded sites are most optimal.[53]
Additionally, sulfates and other salts were deemed favorable to ovipositing females in a laboratory setting but sulfate concentrations in the field may be too low for this effect to be significant.[54] Substrate texture was also determined to be a factor contributing to oviposition, with studies of egg laying on sand particle size indicating a preference for sand particles sized from 0.33 to 0.62 mm.[55]
Adult female mosquitoes ready to lay eggs differ from other adult females in many important behaviors. They perform a special flight at ages 7, 12, and 17, following a 5-day cycle.[23] Changes in diet have effects on flight in males and females: males fed sugar alone exhibited changes in flight patterns that resembled cyclic swarming, females fed sugar alone exhibited consistent flight patterns consisting of a 4-week cycle of flight 40 minutes during dark and 20 minutes during light, females fed sugar and blood experienced reduced flight after 2 weeks, and females fed blood alone flew no more than 10 days.[40] Starved females later fed blood stayed sedentary for 8 hours before returning to flight.[40] Flights are occur with the purpose of acquiring nectar, with flight distance depending on wind speed, direction, landscape, and nectar availability.[21] Females typically fly 2–5 miles in search of nectar, but flights ranging 30 miles have been recorded as a result of other flight factors.[21] Adults searching for a blood meal may also fly up to 25 miles.[19]
Flight patterns are these mosquitoes are closely related to light sensitivity, as flight patterns increase with strength of moonlight: females increase flight activity from 95% at quarter moon to 546% at full moon.[56] Male and female adult mosquitoes are repelled by light,[31] allowing mosquitoes to be caught with light traps.[8][57] However, females ready to lay eggs to not exhibit this behavior.[23] In an experimental setting, mosquitoes raised under conditions of 12 hr light : 12 hr dark were found to exhibit flight activity at both light-off and light-on periods in a bimodal alternans pattern. Mosquitoes adjusted to new light conditions within 24–36 hours, in which a delayed light-off resets the pattern but an early light-off does not.[6]
Adult males begin forming top-swarms beginning at an age of 4 days and lasting until 2–3 weeks of age.[23] These swarms form every evening and morning at a fixed location and time[23] and last for a maximum of 30 minutes.[21] In field observations of Ae. taeniorhynchus in Florida, morning and evening swarms were typically halfway finished by the time point of 4 minutes before and after twilight, respectively.[23] The initial stimulus for swarming behavior is unknown, but time spent swarming depends on sensitivity of individual males to the swarming driving force and swarm size, with small swarms lasting for 12 minutes and large swarms lasting for 27 minutes.[23] These swarms are characterized as transient passage swarms, where males participate in the swarm for 1.5 minutes at a time rather than the full-time.[23] Despite the act of males forming top-swarms, mating has not been observed to coincide with swarming.[23]
Parasites of this species include Amblyospora polykarya, a species of Microspora that lasts for a single generation on Ae. taeniorhynchus,[58] and Goelomomyces psorophorae, a fungus impacting mosquito ovaries that stops egg maturity and kills all larvae.[59]
Blood meal analysis and PCR-based parasite screening of mosquitoes in the Galapagos Islands suggested relationships between the species and Hepatozoon parasites infecting reptiles in the area.[38] The occurrence of a mixed Hepatozoon population in the reptile host suggests that Ae. taeniorhynchus caused a breakdown of the host-species relationship between some Heptazoon parasties and native reptiles.[38] In a topological analysis of parasitism in the food web, Ae. taeniorhynchus, along with Culex tarsalis, was found the most significant organisms within a predator-parasite sub-web, meaning they have the most food web connections among organisms mapped.
Ae. taeniorhynchus is a carrier for West Nile Virus, mosquito iridescent virus,[60] the eastern and western type of equine encephalomyelitis,[61] Venezuelan equine encephalomyelitis virus,[3] and yellow fever virus.[62] Experimental studies also established that the species is capable of mechanical transmission of Bacillus anthracis.[63] Experimental studies regarding Rift Valley fever virus showed that infectivity is independent of temperature, but viral dissemination and transmission is faster at higher temperatures.[64]
This species can transmit Dirofilaria immitis, a filarial worm that can cause heartworm in dogs.[4] Infection by D. immitis occurs through parasite establishment in the Ae. taeniorhynchus Malpighian tubules in a process that changes the microvillar border to impede fluid transport.[65] The parasite takes up to 48 hrs to establish itself in its host; establishment may not occur if the host is resistant.[65] This parasite was also seen to spread to flightless cormorants in the Galapagos, with gene flow analysis correlating parasitic infection with Ae. taeniorhynchus migration patterns and suggesting that Ae. taeniorhynchus is the likely vector for transmission.[22]
This species of mosquito is considered a pest among humans, with Florida districts attempting to control the mosquitoes since 1927 and having spent US$1.5 million on insect control in 1951.[8] Copper acetoarsenite, known as Paris green, is used as an insecticide for Ae. taeniorhynchus larvae at the species breeding site, since the substance acts as a toxic stomach poison.[66] DDT, another insecticide, was also deemed to be effective against the salt marsh mosquitoes and has been used for Ae. taeniorhynchus treatment in the past.[67] Trap-bait combinations tested against the species indicate that CDC-type traps with carbon dioxide, octenol, and heat as bait increase the trapping success of Ae. taeniorhynchus.[68]
Humans have also tried to limit biting from Ae. taeniorhynchus because it flies very fast, and they start the blood extraction quickly, compared to the average mosquito, by wearing chemically treated protective clothing. Clothing treated with permethrin [(3-phenoxyphenyl)methyl (±) cis/trans 3-(2-dichloroethenyl)2, 2-dimethylcyclopropanecarboxylate] alongside application of deet (N,N-diethyl-m-toluamide) to the skin were shown to be extremely effective in reducing mosquito bites compared to usage of only one form of protection or no protection.[69] The Off! Clip-on Mosquito Repellent device, which releases pyrethroid insecticide metofluthrin in vapor form, was also evaluated against Ae. taeniorhynchus in two Florida field location and was found to provide 79% protection from mosquito bites for 3 hrs.[70]
Other toxins have been identified against Ae. taeniorhynchus. Bacillus thuringiensis var. kurstaki (HD-1) can produce a parasporal crystal in the form of a toxic inclusion body.[71] Proteins isolated from a parasporal crystal, yielded two distinct proteins of types k-1 and k-73, of which only k-1, a 65 kD protein, was found to be toxic to Ae. taeniorhynchus larvae.[71]
Aedes taeniorhynchus, or the black salt marsh mosquito, is a mosquito in the family Culicidae. It is a carrier for encephalitic viruses including Venezuelan equine encephalitis and can transmit Dirofilaria immitis. It resides in the Americas and is known to bite mammals, reptiles, and birds. Like other mosquitoes, Ae. taeniorhynchus adults survive on a combination diet of blood and sugar, with females generally requiring a blood meal before laying eggs.
This mosquito has been studied to investigate its development, physiological markers, and behavioral patterns, including periodic cycles for biting, flight, and swarming. This species is noted for developing in periodic cycles, with high sensitivity to light and flight patterns that result in specific wingbeat frequencies that allow for both species detection and sex distinction.
Ae. taeniorhynchus is known to be a pest to humans and mechanisms for controlling Ae. taeniorhynchus populations have been developed. The United States has spent millions of dollars to control and contain Ae. taeniorhynchus.
Aedes taeniorhynchus, o el mosquito negro de las marismas es un mosquito de la familia Culicidae. Es portador del virus encefalíticos, incluida la encefalitis equina venezolana y transmite la Dirofilaria immitis. Reside en América y es conocido por picar mamíferos, reptiles y aves. Como otros mosquitos, Aedes taeniorhynchus. Los adultos de taeniorhynchus sobreviven con una dieta combinada de sangre y azúcar, y las hembras generalmente requieren una ingestión de sangre antes de poner huevos.[3][4][5]
Este mosquito ha sido estudiado para investigar su desarrollo, marcadores fisiológicos y patrones de comportamiento, incluidos los ciclos periódicos de picadura, vuelo y enjambre. Esta especie se caracteriza por desarrollarse en ciclos periódicos, con alta sensibilidad a la luz y los patrones de vuelo que dan como resultado frecuencias específicas de aleteo que permiten tanto la detección de especies como la distinción de sexos.[6][7]
Aedes taeniorhynchus es conocido por ser una plaga para los humanos y los mecanismos para controlar Ae. Se han desarrollado poblaciones de taeniorhynchus. Estados Unidos ha gastado millones de dólares para controlar y contener Ae. taeniorhynchus.[8]
El entomólogo alemán Christian Rudolph Wilhelm Wiedemann describió al Aedes taeniorhynchus. (Ochlerotatus) en 1821. Los nombres alternativos de la especie incluyen Culex taeniorhynchus (Wiedemann, 1821), Ochlerotatus taeniorhynchus (Wiedemann, 1821) y Culex damnosus (Say 1823). Aedes niger, también conocida como Aedes portoricensis, es una subespecie de Ae. taeniorhynchus. Se puede identificar por su última articulación tarsiana posterior, que es mayoritariamente negra en lugar de bandas blancas. Reside en Florida y puede migrar hasta 95 millas (153 km). El análisis de datos de microsatélites sobre los genes de Ae. taeniorhynchus que vive en las Islas Galápagos muestra una diferenciación genética entre las poblaciones de mosquitos costeros y de las tierras altas. Los datos indican un flujo mínimo de genes entre las poblaciones que solo ocurre durante los períodos de mayor precipitación. Las diferencias genéticas sugieren que las diferencias de hábitat llevaron a impulsar la adaptación y la divergencia en las especies, lo que eventualmente condujo a una futura especiación. Los mosquitos de las tierras altas tienen características poblacionales características de un efecto fundador debido a una baja diversidad genética que se manifiesta como una baja heterocigosidad y una baja riqueza alélica, que puede haber resultado de la latencia de los huevos durante los períodos de sequía.[9][10]
Los adultos de aedes taeniorhynchus son en su mayoría negros con áreas de bandas blancas. Aparece una sola banda blanca en el centro de la probóscide, varias bandas blancas abarcan los extremos distales de las patas siguiendo las articulaciones de las patas y las últimas articulaciones de las patas traseras están completamente coloreadas de blanco. Las alas de taeniorhynchus son largas y estrechas con venas escamosas. La investigación experimental de la coloración evolutiva de Ae. taeniorhynchus arrojó resultados negativos. Los mosquitos criados en condiciones de oscuridad, fondos de color negro, blanco o verde y condiciones de iluminación de luz fluorescente o luz solar, no mostraron cambios de color en el cuerpo graso ni en la cápsula de la cabeza, silla de montar o sifón. Se sugiere que esta falta de coloración críptica se debe a la falta de amenaza para la especie; debido a que el hábitat de la especie es una fuente de agua temporal utilizada para el crecimiento de las larvas, este entorno temporal tiene pocos depredadores y relativamente poco peligro.
Los machos y las hembras se pueden distinguir en función de sus antenas: los machos tienen antenas plumosas (parecidas a plumas) mientras que las antenas de las hembras tienen escaso pelo.[11] [12] [13]
Los enjambres del aedes taeniorhynchus pueden detectarse a través del sonido. Los ruidos con frecuencias entre 0,3-3,4 kHz a un nivel de sonido de 21 dB se pueden detectar a una distancia de 10 a 50 m. Se puede escuchar un mosquito individual a una distancia de 2 a 5 cm cuando el nivel de sonido aumenta a 22-25 dB. Los mosquitos machos y hembras también se pueden distinguir por sus frecuencias de aleteo, que son de 700 a 800 Hz para los machos y de 400 a 500 Hz para las hembras. Como resultado, los sonidos de vuelo se utilizan para determinar la actividad de vuelo y distinguir el sexo de los grupos.
Los mosquitos aedes tienen un microbioma característico que modula los efectos de la dieta. Se informa que la composición del microbioma difiere entre machos y hembras en los mosquitos aedes, como aedes albopictus y aedes aegypti. Es decir, en un aedes albopictus, los machos se alimentan de néctar para adquirir actinobacteria, mientras que las hembras contienen proteobacteria (como enterobacteriaceae) que median los niveles de estrés redox causado por la ingesta de sangre.[14]
Las principales distinciones físicas entre aedes taeniorhynchus y otras especies provienen de las bandas blancas que cubren varias partes del cuerpo a lo largo de aedes taeniorhynchus. La especie, como otros mosquitos aedes, exhibe bandas basales del abdomen, pero el aedes taeniorhynchus también exhibe palpos de punta blanca y un anillo central blanco en la probóscide.
Esta especie se parece a aedes sollicitans, excepto por sutiles diferencias en las etapas larvaria y adulta. En la etapa larvaria, Ae. taeniorhynchus tiene un tubo de respiración más corto, sus parches de escamas son redondeados en lugar de puntiagudos en las puntas, y las espinas que recubren los bordes de cada parche de escamas son más pequeñas cerca de la base del parche de escamas. En la etapa adulta, Ae. taeniorhynchus es más pequeño y mayormente negro, mientras que Ae. sollicitans es de color marrón dorado. La especie también tiene similitud con Aedes jacobinae, que cae dentro del subgénero Taeniorhynchus debido a su estructura particular de hipopigio, pero se considera una especie distinta porque no tiene marcas en las patas. De manera similar, esta especie también se puede distinguir del Aedes albopictus, comúnmente conocido como mosquito tigre asiático, como aedes taeniorhynchus, a diferencia de aedes albopictus, no tiene marcas en su espalda.[15]
El aedes taeniorhynchus se distribuye ampliamente en América del Norte y del Sur, aunque está más concentrado en las regiones del sur. En el momento del descubrimiento inicial de la mosca, la especie residía en regiones costeras y luego se trasladó gradualmente hacia el resto del continente americano. El análisis del flujo de genes derivado de los datos de microsatélites indicó que los mosquitos ubicados en las Islas Galápagos en la Isla del Pacífico con frecuencia migran entre islas en forma aislada por distancia. La incidencia de los puertos fue un factor importante que contribuyó a la migración, lo que sugiere que el transporte con ayuda humana contribuyó a la migración entre islas.[16][17][18] [19]
El aedes taeniorhynchus reside en hábitats con una fuente de agua temporal, lo que hace que los manglares y las marismas saladas u otras áreas con suelo húmedo sean lugares populares para la puesta de huevos y el crecimiento inmaduro. Estos hábitats son muy variables, pero a menudo tienen una alta salinidad con un contenido de sal soluble observado en el suelo de al menos 1644 ppm. En el caso de condiciones ambientales de sequedad y bajas temperaturas que son desfavorables para la eclosión de los huevos, los huevos pueden permanecer inactivos durante años. Los factores que controlan la escala del crecimiento de A. taeniorhynchus durante la preemergencia dependen de las condiciones ambientales que coincidan con el nivel de humedad y la temperatura. En el sur de Florida, los factores principales son la altura de la marea y la cantidad de lluvia, mientras que los sitios en California dependen únicamente de la altura de la marea. En Virginia, estos factores se limitan a los niveles de lluvia y temperatura. Los factores generalmente favorables pueden volverse negativos en valores extremos, lo que hace que la tasa de supervivencia disminuya. El exceso de agua elimina los huevos de los mosquitos y las temperaturas extremadamente altas pueden provocar la evaporación de la fuente de agua.[20][21]
Los lugares de reproducción de aedes taeniorhynchus a menudo están en contacto con vegetación como Distichlis spicata (hierba de púas) y Spartina patens (heno de pradera salada) en las marismas y Batis maritima (saltwort) y especies del género Salicornia (glassworts) en los manglares. Esta especie de mosquito se encuentra muy cerca de otros mosquitos que residen en marchas. Estos incluyen Aedes sollicitans (mosquito de las marismas del este), Anopheles bradleyi y A. atropos.[17]
Según estudios de campo de observación, aedes taeniorhynchus lleva a cabo varias tendencias de comportamiento en diferentes etapas de la vida. Se encontró que el crecimiento y la pupación de esta especie se ven afectados por factores ambientales de nutrición, densidad de población, salinidad, luz-oscuridad y temperatura.[22]
Las hembras ponen huevos en tierra seca y la eclosión de los huevos es provocada por la presencia de agua, como lluvia o inundaciones. El rendimiento de la puesta de huevos de las hembras, un indicador de fecundidad, difiere según la dieta: en poblaciones de baja autogenia, las hembras autógenas raras cada una pusieron menos de 30 huevos, mientras que el rendimiento de huevos fue significativamente mayor en poblaciones con mayoría de hembras autógenas. Los huevos puestos en las condiciones adecuadas de temperatura y humedad se someten a embriogénesis y luego permanecen inactivos hasta la eclosión.[23] [24] [22]
Tras la eclosión, la especie progresa a través de 4 estadios larvarios: los primeros 3 estadios se ven afectados principalmente por la temperatura, con efectos menores por la salinidad; el cuarto estadio se ve afectado por todos los factores ambientales. En el cuarto estadio, el aumento de alimentos aceleró el tiempo de desarrollo, mientras que el hacinamiento y la salinidad retrasaron el crecimiento. La temperatura preferida para los 4 estadios está entre 30 ° C y 38 ° C, pero la temperatura promedio preferida aumenta con la edad. El primer estadio prefiere una temperatura promedio de 31,8 ° C y el cuarto estadio temprano prefiere una temperatura de 34,6 °.El cuarto estadio tardío, sin embargo, tiene una temperatura preferida más baja que el cuarto estadio temprano, a 33.0 °. Se encontró que las larvas hambrientas tienen un rango de temperatura preferido más amplio que se centra en temperaturas más bajas. Se encontró que las colonias de larvas de laboratorio cultivadas durante años a 27.0 ° C prefieren temperaturas consistentemente más bajas. Se observó que las larvas del cuarto estadio beben agua de mar (100 nL / h) y secretan líquido hiperosmótico a través del recto. Ete líquido es similar al agua de mar pero con niveles de potasio 18 veces más altos. Debido a que el líquido secretado no permite el equilibrio osmótico con el líquido ingerido, los estudios sugieren que las papilas anales ayudan en la secreción de sal.[22]
Todos los factores ambientales afectan la pupación con respecto al ritmo diurno del insecto, que tiene un período de 21,5 horas. Los factores que conducen a un mayor período de pupa incluyen la eliminación de los ciclos de luz y oscuridad con condiciones de oscuridad total o luz, aumento de la salinidad y hacinamiento. Estas tendencias continuaron adhiriéndose a una preferencia por temperaturas cercanas a 27 ° C o 32 ° C. Las pupas también exhiben formación de agregación diferencial debido a estos factores ambientales. Las agregaciones de tipo racimo se forman junto con el apiñamiento temporal y el exceso de comida, mientras que las agregaciones de tipo bola pueden manifestarse por amontonamiento temporal pero falta de alimento. A temperaturas constantes más bajas de 22 ° C y 25 ° C, pueden formarse agregaciones de tipo racimo, pero temperaturas más altas de 30 ° y 32 ° C inhiben la formación de agregaciones. Las agregaciones produjeron pupas con pesos corporales secos ligeramente más pesados y promovieron la sincronización del desarrollo en la ecdisis y una mayor probabilidad de migración en la emergencia.[22] [25]
Los mosquitos machos y hembras emergen de sus sitios de huevos de manera similar. Permanecen en sus fuentes de agua durante 12-24 horas. Luego, los adultos migran lejos del terreno de puesta de huevos en el transcurso de 1 a 4 días. Los diferentes sexos exhiben una migración diferencial, con la mayoría de las hembras viajando al menos 20 millas (32 km) y la mayoría de los machos viajando no más de 2 millas (3,2 km). La migración femenina sigue un patrón aleatorio sin limitación en la dirección de la migración y la migración ocurre a lo largo de un ciclo de 5 días. Los machos inicialmente viajan con las hembras hasta que llegan a un punto de parada de 1 a 2 millas (1,6 a 3,2 km), donde reemplazan la migración con enjambres.[20] [8]
Los patrones de vuelo se establecen en la etapa adulta y no se ven afectados por patrones de comportamiento de etapas anteriores de la vida. Los adultos comienzan a morder el día 4 y siguen un ciclo de 5 días hasta la muerte. Entre los sexos, la intensidad máxima de las picaduras se produce en las hembras a los 4, 9 y 14 días de edad. Las hembras adultas de mosquitos siguen viviendo y poniendo huevos durante 3 a 4 semanas antes de morir. Aquellos que sobreviven por más tiempo continúan mordiendo pero dejan de poner huevos.[6] [20]
El aedes taeniorhynchus es portador del virus del Nilo Occidental, virus iridiscente del mosquito,[26] el tipo oriental y occidental de encefalomielitis equina,[27] Virus de la encefalomielitis equina venezolana,[28] y fiebre amarilla virus.[29] Los estudios experimentales también establecieron que la especie es capaz de transmisión mecánica de Bacillus anthracis.[30] Los estudios experimentales sobre virus de la fiebre del Valle del Rift mostraron que infectividad es independiente de la temperatura, pero la diseminación y transmisión viral es más rápida a temperaturas más altas.[31]
Esta especie puede transmitir Dirofilaria immitis, un gusano filarial que puede causar gusano del corazón en perros [3] Infección por D. immitis que ocurre a través del establecimiento de parásitos en el aedes taeniorhynchus Túbulos de Malpighi en un proceso que cambia el borde microvillar para impedir el transporte de líquidos.[32] El parásito tarda hasta 48 horas en establecerse en su huésped; el establecimiento puede no ocurrir si el huésped es resistente.[32] También se observó que este parásito se propagaba a los cormoranes no voladores en las Galápagos, y el análisis de flujo genético correlacionó la infección parasitaria con aedes taeniorhynchus patrones de migración y sugiriendo que aedes taeniorhynchu es el vector probable de transmisión.[19]
Datos: Q13543877
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Aedes taeniorhynchus, o el mosquito negro de las marismas es un mosquito de la familia Culicidae. Es portador del virus encefalíticos, incluida la encefalitis equina venezolana y transmite la Dirofilaria immitis. Reside en América y es conocido por picar mamíferos, reptiles y aves. Como otros mosquitos, Aedes taeniorhynchus. Los adultos de taeniorhynchus sobreviven con una dieta combinada de sangre y azúcar, y las hembras generalmente requieren una ingestión de sangre antes de poner huevos.
Este mosquito ha sido estudiado para investigar su desarrollo, marcadores fisiológicos y patrones de comportamiento, incluidos los ciclos periódicos de picadura, vuelo y enjambre. Esta especie se caracteriza por desarrollarse en ciclos periódicos, con alta sensibilidad a la luz y los patrones de vuelo que dan como resultado frecuencias específicas de aleteo que permiten tanto la detección de especies como la distinción de sexos.
Aedes taeniorhynchus es conocido por ser una plaga para los humanos y los mecanismos para controlar Ae. Se han desarrollado poblaciones de taeniorhynchus. Estados Unidos ha gastado millones de dólares para controlar y contener Ae. taeniorhynchus.
Aedes taeniorhynchus adolah saikua rangik dari famili Culicidae. Spesies ko juo marupokan bagian dari ordo Diptera, kelas Insecta, filum Arthropoda, dan kingdom Animalia.
Spesies iko mahisok darah dari vertebrata hiduik.
Aedes taeniorhynchus adolah saikua rangik dari famili Culicidae. Spesies ko juo marupokan bagian dari ordo Diptera, kelas Insecta, filum Arthropoda, dan kingdom Animalia.
Spesies iko mahisok darah dari vertebrata hiduik.
Aedes taeniorhynchus is een muggensoort uit de familie van de steekmuggen (Culicidae).[1] De wetenschappelijke naam van de soort is voor het eerst geldig gepubliceerd in 1821 door Wiedemann.
Bronnen, noten en/of referenties
Aedes taeniorhynchus é um espécie de mosquito do Género Aedes, pertencente à família Culicidae. Presentes em Galápagos, ao conrários de outros mosquitos, que usualmente sugam o sangue de mamíferos e aves, essa espécie habitualmente suga o sangue de répteis.[1]
Aedes taeniorhynchus é um espécie de mosquito do Género Aedes, pertencente à família Culicidae. Presentes em Galápagos, ao conrários de outros mosquitos, que usualmente sugam o sangue de mamíferos e aves, essa espécie habitualmente suga o sangue de répteis.
