Prevalence and seasonal distribution of anopheline fauna in district Bikaner (Rajasthan).

A survey was carried out during 1989-91 to study the prevalence and distribution of anopheline mosquitoes in 12 villages located in all the 4 tehsils of Bikaner district. Six species, viz. Anopheles subpictus (34.7%), An. stephensi (33.3%), An. culicifacies (18.0%), An. annularis (12.1%), An. pulcherrimus (1.1%) and An. barbirostris (0.8%), were collected. An. stephensi was present throughout the year and the other species were present during the monsoon and post-monsoon periods. During the peak winter period (Dec-Jan) only An. stephensi was present and in low density. An. culicifacies made its appearance only during the spring season and continued up to the middle of November. An. subpictus, An. pulcherrimus, An. barbirostris and An. annularis were found only during the monsoon and post-monsoon periods. An. subpictus was the most abundant species during the monsoon, and so was An. stephensi during the spring season in indoor habitats.