We used a histologic technique to detect multiple bloodfeeding in a single gonotrophic cycle by Culiseta melanura. In a laboratory study with colonized mosquitoes, 77% (10/13) of known multiple meals were detected when the interval between meals was 24-30 h. Outside that range, known multiple meals were undetectable with this method. No multiple blood meals were detected in 653 wild engorged mosquitoes collected during 3 consecutive years from the Pocomoke Swamp in Maryland. Although previous studies have shown that Cs. melanura will feed twice in the same evening, it rarely, if ever, takes multiple blood meals at 24-h intervals. Our study also indicates that a thorough laboratory standardization is required prior to application of the histologic technique to species for which it has not been studied. This would include a time-series analysis to define species-specific limits for detecting known multiple meals.
