INTERSPECIFIC VARIATION IN DESICCATION SURVIVAL-TIME OF AEDES (STEGOMYIA) MOSQUITO EGGS IS CORRELATED WITH HABITAT AND EGG SIZE

Survival times of eggs under three humidity conditions (42%, 68%, 88% RH) were investigated among Aedes (Stegomyia) mosquitoes from temperate and tropical zones (5 species and 20 geographical strains). This subgenus tends to occupy small aquatic sites as larvae, where desiccation resistance of eggs is necessary during habitat drought. Interspecific comparison showed that the egg survival time was correlated with egg volume and dryness of source locality, and probably with habitat. Aedes aegypti is associated most with arid climate and human-disturbed habitats - its large eggs survived the longest periods at all humidities. Aedes albopictus ranges from tropics to temperate zones and inhabits both disturbed and forest habitats - its eggs were less desiccation-resistant than A. aegypti eggs. The survival times for forest species eggs (A. riversi, A. galloisi, A.flavopictus) were variable at high humidities but at the lowest humidity were consistently shorter than for eggs of A. aegypti and A. albopictus.