Morphology and biology of Culex tritaeniorhynchus

The mosquito species Culex tritaeniorhynchus Giles is part of the Culex vishnui subgroup, which also includes Culex pseudovishnui Colless and Cx. vishnui Theobald. It is a relatively small, reddish brown species. The proboscis is predominantly dark scaled, with a narrow median pale ring. Tarsi predominantly dark scaled with narrow basal and apical pale rings on tarsomeres I–IV, more distinct on fore legs. Wing veins are entirely dark scaled.

The females feed primarily on domestic animals such as cattle and pigs, but will bite man in their absence. They mainly bite outdoors between sunset and midnight, but may enter cattle sheds and dwellings and bite man during any time of the night. Biting activity of the female Cx. tritaeniorhynchus have been reported to have two peaks, the first at 9 p.m. and the second at 2 a.m.

Following copulation, females take a blood-meal and 2-3 days later lay their eggs in rafts comprising 200 eggs locked together in a boat-shaped structure, onto the water surface. After 1-3 days the eggs are ready to hatch. Larvae need 7-15 days to complete their development (depending on temperature and food supply). The pupal stage lasts 2-4 days. In mid-summer it takes 2 weeks from egg to first oviposition.

Larvae of Cx. tritaeniorhynchus can be found in various temporary and permanent ground water habitats that are sunlit and contain vegetation. The water may be fresh or slightly brackish. That kind of habitats are ground pools, streams, swamps, shallow marshes, irrigation ditches, rice fields and animal hoof prints

In the temperate zone Cx. tritaeniorhynchus can hibernate as adult whether in northern places the densities of adults increase because of the immigration of the population of this species from the south.

Cx. tritaeniorhynchus can disperse long distance under natural conditions. The species has the ability to fly 5 km from the breeding site in only one day and the maximum dispersal distance during seven days is 8.4 km.

Editing: Ioanna Lytra
Agronomist, MScD Student
Agricultural University of Athens

The literature review and the studies conducted from the Agricultural University of Athens are derived from a research that has been co-financed by the European Union (European Social Fund – ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF) – Research Funding Program: Heracleitus II. Investing in knowledge society through the European Social Fund.