Aedes dorsalis
{{Short description|Species of mosquito}}
{{italic title}}
{{Taxobox
| name = Aedes dorsalis
| image = File:Aedes dorsalis.jpg
| image_upright =
| image_alt =
| image_caption =
| regnum = Animalia
| phylum = Arthropoda
| classis = Insecta
| ordo = Diptera
| familia = Culicidae
| genus = Aedes
| subgenus = Ochlerotatus
| species = A. dorsalis
| binomial = Aedes dorsalis
| binomial_authority = (Meigen, 1830)
}}
Aedes dorsalis is a mosquito species in the genus Aedes, subgenus Ochlerotatus. Commonly known as the summer salt marsh mosquito, this medium-sized mosquito is distinguishable by its white-scaled abdomen and legs with white rings. It has a broad distribution across the Nearctic and Palearctic regions, including North America and parts of Europe and Asia, where it inhabits flood-prone and saline areas. While it is an aggressive biter and a nuisance pest, its primary medical significance stems from its role as a vector for California encephalitis virus. Unlike some well-known Aedes species, such as Aedes aegypti or Aedes albopictus, it is not a significant vector for major diseases like dengue, Zika, or chikungunya.
Description
Aedes dorsalis adults are medium-sized mosquitoes with distinctive markings. The proboscis is dark with pale scales at the base, and the thorax features white hypostigmal and postprocoxal scales, with the scutum displaying two dark stripes. The wings have a mix of white and black scales, creating distinct patterns. The legs, especially the hind tarsi, bear white rings at the base and apex of each segment. The abdomen is almost entirely covered with white scales, giving it a striking appearance. Larvae are characterized by specific setae on the antenna and head, rounded comb scales, and an incomplete saddle on segment X.{{cite web |title=Aedes dorsalis |url=https://wrbu.si.edu/vectorspecies/mosquitoes/dorsalis |website=Walter Reed Biosystematics Unit |access-date=2023-10-05}}
Distribution
Aedes dorsalis is widely distributed across the Nearctic and Palearctic regions. In North America, its range extends from Canada to Mexico, with notable populations in California coastal marshes and inland saline areas. In Europe and Asia, it occurs in countries including Albania, Austria, Belarus, Belgium, Bulgaria, Croatia, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iraq, Ireland, Italy, Japan, Kazakhstan, Kosovo, Latvia, Lithuania, Moldova, Mongolia, Netherlands, Norway, Poland, Romania, Russia, Serbia, Slovakia, Slovenia, South Korea, Spain, Sweden, Switzerland, Taiwan, Tajikistan, Turkey, Ukraine, the United Kingdom, and the United States.{{cite GBIF |title=Aedes dorsalis (Meigen, 1830) |id=1651209 |access-date=2023-10-05}} It thrives in flood-prone, grassy areas and is uniquely adapted to tolerate saline environments, making it common in both freshwater and saltwater habitats such as coastal marshes and inland saline ponds.
Behavior and ecology
The life cycle of Aedes dorsalis is multivoltine, meaning it can produce multiple generations per year depending on environmental conditions. Females lay eggs in late summer or autumn in moist soil or mud, often in flood-prone areas. These eggs can enter diapause—a dormant state—and hatch the following spring when flooded by rain or snowmelt. Larvae develop in semi-permanent pools, favoring unshaded, grassy margins with fresh or saline water. Adults emerge from spring through autumn, with females being crepuscular-nocturnal biters, active primarily at dawn and dusk or on cloudy days. They are known for their aggressive biting behavior and can disperse up to {{cvt|30|km}} from breeding sites. Males form mating swarms above the ground to attract females. This adaptability to varying water conditions and its dispersal ability contribute to its widespread presence.{{cite book |last1=Becker |first1=N. |last2=Petrić |first2=D. |last3=Zgomba |first3=M. |last4=Boase |first4=C. |last5=Madon |first5=M. |last6=Dahl |first6=C. |last7=Laney |first7=S. |title=Mosquitoes and Their Control |edition=2nd |publisher=Springer |year=2010 |doi=10.1007/978-3-540-92874-4 |isbn=978-3-540-92873-7}}
Medical significance
Aedes dorsalis is primarily a nuisance pest due to its aggressive biting, which can irritate humans and animals. It is a known vector for California encephalitis virus and Western equine encephalitis virus, capable of transmitting the virus transovarially (from infected females to their offspring) and trans-stadially (across life stages, such as from larva to adult).{{Cite journal |last=Turell |first=Michael J. |last2=Reeves |first2=William C. |last3=Hardy |first3=James L.
|title=Transovarial and Trans-Stadial Transmission of California Encephalitis Virus in Aedes dorsalis and Aedes melanimon |year=1982 |url=https://www.ajtmh.org/view/journals/tpmd/31/5/article-p1021.xml |journal=The American Journal of Tropical Medicine and Hygiene |volume=31 |issue=5 |pages=1021–1029 |doi=10.4269/ajtmh.1982.31.1021 |issn=0002-9637}} However, unlike its relatives Aedes aegypti and Aedes albopictus, it is not significantly associated with major global diseases such as dengue, Zika, or chikungunya. The Walter Reed Biosystematics Unit notes no specific vector hazard reports for this species, suggesting its medical importance is limited compared to other Aedes species.