Seasonal prevalence and host visitation ofMansonia mosquitoes in Trivandrum city with a note on mite infestation

Abstract

A study relating to seasonal prevalence and host visitation of Mansonia mosquitoes in Trivandrum city was carried out between August 1984 and July 1985. The area chosen was the one which is a perennial breeding source for Mansonia mosquitoes. Only Mansonia uniformis and Mansonia annulifera were prevalent in this area of which the former was found to be the predominant species. Decrease in the number of Mansonia annulifera from the survey conducted during the previous year may be due to the disappearance of Pistia stratiotes and its replacement by Salvinia auriculata. Rainfall and temperature are the two important environmental factors which influence the number of Mansonia mosquitoes visiting the host. The maximum number of adults of Mansonia uniformis was collected during February to June 1985. No swarm of Mansonia uniformis was encountered during the present study, however, males were found to wait and mate with the resting as well as blood fed females in the vicinity of the host. Both sexes of Mansonia mosquitoes were parasitized by Arrenurus and limnesiid species of water mites. Maximum parasitization was seen during July 1985.