Culex tritaeniorhynchus

Culex (Culex) tritaeniorhynchus is a species of mosquito and is the main vector of the disease Japanese encephalitis.[1] This mosquito is a native of northern Asia, and parts of Africa (northeast and sub-Saharan).[2] Females target large animals for blood extraction, including cattle and swine, and are strongly anthropophilic.[3]

Culex tritaeniorhynchus
Scientific classification Edit this classification
Domain: Eukaryota
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Diptera
Family: Culicidae
Genus: Culex
Species:
C. tritaeniorhynchus
Binomial name
Culex tritaeniorhynchus
Giles, 1901
Synonyms
  • Culex biroi Theobald, 1905
  • Culex summorosus Dyar, 1920

Habitat

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The larval habitat of Culex tritaeniorhynchus primarily consists of low lying water logged areas such as grasses and fallow rice fields, but this species can also be found in wells, ponds, ditches and has been reported in urban environments in close proximity to human populations, such as water storage containers in houses.[4][5] Culex tritaeniorhynchus is extremely common and widespread. It can be found in locations where the annual mean temperature ranges from 8.2 - 28.9°C, with elevations of a maximum 838m above sea level.[6] Recorded presence of Culex tritaeniorhynchus through surveys and mosquito collections list the species as being present in Bangladesh, Cambodia, India, Indonesia, Malaysia, Myanmar, Nepal, Singapore, Sri Lanka, Thailand and Viet Nam.[3][6] Attempts have been made to model the distribution of Culex tritaeniorhynchus using species distribution models; the predicted geographic distribution of the vector in 2011 can be seen below,[6] however, the species may have expanded its distribution in current years due to changes in global climate.[7]

 
Darker areas indicate areas that are likely to have suitable habitat for this vector species while lighter areas indicate areas of that are less suitable for the vector.

Morphology and biology

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Culex tritaeniorhynchus is part of the Culex vishnui subgroup, which also includes Culex pseudovishnui and Culex vishnui.[8] As the species are very morphologically similar, it is often difficult to identify the adult specimens collected from the field. Culex tritaeniorhynchus is a relatively small, reddish brown species.[9] It can be identified by the dark brown scaling on the vertex and scutum, the accessory pale patches basal to the pale band on the ventral surface of the proboscis, and the narrow apical dark ring on the hind femur.[3]

Biting habits

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Adult emergence typically commences around mid-afternoon, and reaches a maximum around dusk.[10] Culex tritaeniorhynchus generally has a biphasic biting profile - with feeding peaking around 7pm, declining throughout the midnight hours, then peaking again around 3am.[11][12][13] Periodicity can change dramatically depending on the location, season and climate;[14] further studies are required to determine habits of this vector at each of its different distributions as information on biting activity of vectors can play a vital role in personal protection measures, vector control and biting prevention. Culex tritaeniorhynchus is predominantly an exophilic species which rest outdoors after taking a blood meal, however, this also varies based on geographic location.[15]

References

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  1. ^ Self, L. S.; Shin, H. K.; Kim, K. H.; Lee, K. W.; Chow, C. Y.; Hong, H. K. (1973-01-01). "Ecological studies on Culex tritaeniorhynchus as a vector of Japanese encephalitis". Bulletin of the World Health Organization. 49 (1): 41–47. ISSN 0042-9686. PMC 2481081. PMID 4363396.
  2. ^ Clements, Alan (2012). The Biology of Mosquitoes, Volume 3 Transmission of Viruses and Interactions with Bacteria. CABI. ISBN 978-1845932428.
  3. ^ a b c Reuben, R (1994). "Illustrated keys to species of Culzx (Culex) associated with Japanese Encephalitis in Southeast Asia (Diptera: Culicidae)" (PDF). Mosquito Systematics. Archived from the original (PDF) on 4 March 2016. Retrieved 14 October 2015.
  4. ^ Reuben, Rachel (1971-10-30). "Studies on the Mosquitoes of North Arcot District, Madras State, India Part 5. Breeding places of the Culex vishnui group of species". Journal of Medical Entomology. 8 (4): 363–366. doi:10.1093/jmedent/8.4.363. ISSN 0022-2585. PMID 4400663.
  5. ^ Kanojia, Phool Chand; Paingankar, Mandar S.; Patil, Avinash A.; Gokhale, Mangesh D.; Deobagkar, Dileep N. (2010-01-01). "Morphometric and allozyme variation in Culex tritaeniorhynchus mosquito populations from India". Journal of Insect Science. 10 (1): 138. doi:10.1673/031.010.13801. ISSN 1536-2442. PMC 3388975. PMID 20883134.
  6. ^ a b c Miller, Robin H.; Masuoka, Penny; Klein, Terry A.; Kim, Heung-Chul; Somer, Todd; Grieco, John (2012-06-19). "Ecological Niche Modeling to Estimate the Distribution of Japanese Encephalitis Virus in Asia". PLOS Negl Trop Dis. 6 (6): e1678. doi:10.1371/journal.pntd.0001678. PMC 3378598. PMID 22724030.
  7. ^ Elbers, A (2015). "Mosquitoes and Culicoides biting midges: vector range and the influence of climate change" (PDF). Rev. Sci. Tech. Off. Int. Epiz. 34 (1): 123–137. doi:10.20506/rst.34.1.2349. PMID 26470453. Retrieved 14 October 2015.
  8. ^ Toma, Takako; Miyagi, Ichiro; Crabtree, Mary B.; Miller, Barry R. (Jul 2000). "Identification of Culex vishnui Subgroup (Diptera: Culicidae) Mosquitoes from the Ryukyu Archipelago, Japan: Development of a Species-Diagnostic Polymerase Chain Reaction Assay Based on Sequence Variation in Ribosomal DNA Spacers". Journal of Medical Entomology. 37 (4): 554–558. doi:10.1603/0022-2585-37.4.554. PMID 10916296. S2CID 24427066.
  9. ^ Norbert Becker; Dusan Petric; Marija Zgomba; Clive Boase; Minoo Madon; Christine Dahl; Achim Kaiser (2010). Mosquitoes and Their Control. New York, New York: Springer Science & Business Media. p. 349. ISBN 9783540928744.
  10. ^ Khan, A.Q (1977). "Laboratory observations on developmental rhythms and mating behaviour in Culex tritaeniorhynchus". Mosq. News.
  11. ^ Amerasinghe, F. P.; Indrajith, N. G. (1995-06-01). "Nocturnal biting rhythms of mosquitoes (Diptera Culicidae) in Sri Lanka". Tropical Zoology. 8 (1): 43–53. Bibcode:1995TrZoo...8...43A. doi:10.1080/03946975.1995.10539271. ISSN 0394-6975.
  12. ^ Aslam, Y (1977). "The influence of physiological age on the biting rhythm of Culex tritaeniorhynchus Giles (Diptera : Culcidae)". The Southeast Asian Journal of Tropical Medicine and Public Health. 8 (3): 364–367. PMID 564554.
  13. ^ Kumar, Ashwani; Kabadi, Dipak; Korgaonkar, NandiniS; Yadav, RajpalS; Dash, AdityaP (2012-01-01). "Mosquito biting activity on humans & detection of Plasmodium falciparum infection in Anopheles stephensi in Goa, India". The Indian Journal of Medical Research. 135 (1): 120–6. doi:10.4103/0971-5916.93434. PMC 3307172. PMID 22382193.
  14. ^ Eyo, Joseph Effiong; et al. (2014). "Effects of climatic conditions on the biting density and relative abundance of Simulium damnosum complex in a rural Nigerian farm settlement". Annals of Agricultural and Environmental Medicine. 21 (4): 697–700. doi:10.5604/12321966.1129917. PMID 25528904.
  15. ^ Das, Bina Pani (2004). "Outdoor resting preference of Culex tritaeniorhynchus, the vector of Japanese encephalitis in Warangal and Karim Nagar districts, Andhra Pradesh". J Vector Borne Dis. 41 (1–2): 32–36. PMID 15332484.
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