City mosquito (London Underground mosquito, sewer mosquito)

(Culex pipiens molestus)

Adult:   5 mm

Identification marks

The feeding female’s back body is aligned with the skin surface. Short jaw filaments. The end of the female’s back body is usually blunt-shaped.


This species of mosquito, referred to as the city mosquito or sewer mosquito in Finnish, habits places, where water is left standing for a long time, such as gutters and flower pots. They come into apartments through windows, air ventilation channels and floor drains.


The mosquito bites during the night, causing lumps which may become irritated.



Prevention and extermination

It is recommended to install mosquito nets on windows and air ventilation channels, in order to prevent the mosquitoes getting in to the house. Pour enough hot water into floor drains to change the water in the seal. In evenings, you can spray suitable pesticide into the floor drain.