We compared rates of feeding on human hosts for blood-engorged female Anopheles quadrimaculatus species A, B and C1 collected from daytime resting sites in Manatee Springs State Park, Levy County, Florida during 1992-1993. Quick-blot DNA probes were used to identify mosquito taxa and also the presence of human blood in the mosquito gut. In collections from a campground area, human blood-feeding rates differed significantly among mosquito species (10.7% [19 of 177], 0%, [0 of 62], and 1.2%, [4 of 327]), respectively for species A, B and C1). In collections from a woodland site (1 km from the campground), 1.5% (2 of 129) of the species B females had fed on humans, whereas none of 19 species A or 159 species C1 females had done so. Of the three species in this study area, species A appears the most likely to be a biting pest of humans and a vector of human malaria.
Anopheles perplexens was collected from habitats previously unreported for this species in northern Florida. These habitats included intermittently flooded swamps, water-filled tires, and plastic oviposition cups. First-instar An. perplexens larvae were recovered from soil samples collected in an intermittently flooded swamp that were flooded in the laboratory, suggesting that An. perplexens eggs may survive in the soil during dry periods. Anopheles perplexens larvae were collected from water-filled tires and plastic oviposition cups at sites near Gainesville, FL. Of 30 dissected An. perplexens females collected in updraft CDC traps, all had ovarioles in Christophers's stage II and blood was absent in the midgut. The physiological state of these females indicates that updraft CDC traps collect predominately host-seeking females and that females take one blood meal per gonotrophic cycle.
Anopheles perplexens was collected from habitats previously unreported for this species in northern Florida. These habitats included intermittently flooded swamps, water-filled tires, and plastic oviposition cups. First-instar An. perplexens larvae were recovered from soil samples collected in an intermittently flooded swamp that were flooded in the laboratory, suggesting that An. perplexens eggs may survive in the soil during dry periods. Anopheles perplexens larvae were collected from water-filled tires and plastic oviposition cups at sites near Gainesville, FL. Of 30 dissected An. perplexens females collected in updraft CDC traps, all had ovarioles in Christophers's stage II and blood was absent in the midgut. The physiological state of these females indicates that updraft CDC traps collect predominately host-seeking females and that females take one blood meal per gonotrophic cycle.
Anopheles quadrimaculatus species Cl is a member of the recently described A. quadrimaculatus complex and has been collected from temporary pools in intermittently flooded swamps in north Florida. We examined the hypothesis that species Cl uses persistence in the egg stage as a survival strategy. Species Cl larvae appeared in 40 of 153 samples of dry substrate collected from the floor of four intermittently flooded swamps and flooded with distilled water. Cohorts of first-instar species Cl were collected from temporary pools <24 h after the pools formed and at the same time as first instars of the floodwater mosquitoes Aedes infirmatus and Psorophora ferox appeared. In the laboratory, eggs of species Cl were successfully hatched after storage for up to 28 d on moist filter paper. Survival of species Cl eggs allows this species to exploit a niche used by floodwater mosquitoes.
Updraft CDC traps baited with dry ice were used to monitor changes in the abundance and parity rate of Anopheles quadrimaculatus Say complex mosquitoes in an intermittently flooded swamp in Central Florida during an 18-d period. Mosquitoes collected each day were identified to species using DNA hybridization and isozyme electrophoretic techniques and were dissected to determine follicular maturation and parity. Of 1,178 An. quadrimaculatus mosquitoes identified to species, 4% were species A and 96% were species C. Dissections of females of both species indicated that 98% were nonblood fed and nongravid with ovariole development at Christophers' stage II. Overall parity rates were 0.19 and 0.51 for populations of species A and species C, respectively. The duration of the gonotrophic cycle for species C females was estimated to be 5 d based on the interval between peaks in the number of nulliparous females collected on days 1 and 6 and peaks in the number of parous females collected 5 d later. Significant trends were observed in the number of parous species C females collected each day, indicating that the parity rate could not be used as an unbiased estimator of survivorship.
