Desiccation tolerance in larvae of Culex quinquefasciatus Say, 1823 and Anopheles stephensi Liston, 1901 (Diptera: Culicidae): implications for mosquito control

Abstract

A laboratory assessment of desiccation tolerance in larval stages of mosquitoes Anopheles stephensi Liston, 1901 (Diptera: Culicidae) and Culex quinquefasciatus Say, 1823 (Diptera: Culicidae) was carried out using five temperature levels and three levels of exposure duration as explanatory variables. The increase in the duration of exposure to desiccation from 15 min to 60 min was noted to result in a substantial increase in water loss (in mg) in mosquito larvae. Similarly, the increase in temperature levels was observed to cause larval mortality and a substantial decrease in the emergence of adults. Both the temperature and the duration of exposure to desiccation were found to be influential factors in determining survival and subsequent emergence of adults. Desiccation is a primary factor in determining the survival of mosquito larvae, particularly in the conditions where habitat permanence is uncertain, e.g., in temporary pools and containers serving as mosquito larval habitats. The results of the present study provide a glimpse into the effects of desiccation at varied temperatures and exposure durations on the successful emergence of adults in mosquitoes Cx. quinquefasciatus and An. stephensi. Although primary, the obtained results show that desiccation can be a probable way of regulating the development of mosquito larvae in conditions where the permanence of the habitat for mosquito larvae is uncertain. Further studies on desiccation tolerance may be carried out using different mosquito species that are adapted to temporary pools and containers as sources for breeding.