Biology and control of Taeniorhynchus (Mansonioides) uniformis Theobald, the chief vector of rural filariasis in Ceylon.

Residual spraying of DDT for the control of Taeniorhynchus (Mansonioides) uniformis, the mosquito vector of rural filariasis in Ceylon, was carried out in Induruwa, a village on the west coast of the island. The results showed that the insecticide retained its effectiveness for a period of 4-6 months.During the course of this investigation, various observations were made on the behaviour of T. (M.) uniformis. Its host plants, day-time resting-places, feeding habits, and response to light-particularly moonlight-were recorded. An increase in T. (M.) uniformis prevalence was observed to coincide with the onset of the north-east and south-west monsoons, when the paddy-fields are inundated and become overgrown with Isachne australis, the most common aquatic plant in the area and a favourite breeding-place of this mosquito species.