A Comparison of the Physiological Age of Adult Resting Versus Flying Culex quinquefasciatus (Diptera: Culicidae)

Relatively little is known about the physiological age of resting mosquitoes. In this study, Culex quinquefasciatus had a similar proportion of resting males (75%) as in the flying population (76%), but among the females, there were significant differences between the physiological age of the resting and flying populations. The proportion of unfed resting females (51%) made up a significantly smaller proportion than in the flying female group (82%). By contrast, in the resting group, there were much higher proportions of blood-fed (28% compared with 4%) and to a lesser extent gravid (21% compared with 14%) females. Of the blood-fed females, most of the resting individuals were freshly blood-fed. Both males and females entered the resting traps throughout the day (but none were collected after sunset), with the main peak around dawn. The flying population showed two circadian peaks: a larger peak at dawn and smaller peak after sunset. This indicates a different pattern from that shown in other studies and demonstrates the significant geographic variation within this pan-tropical species.