Thelohania solenopsae Knell, Allen, & Hazard is an entomopathogenic microsporidium that infects imported Þre ants. We documented artiÞcially initiated transmission of T. solenopsae among colonies of the red imported Þre ant, Solenopsis invicta Buren. Microsporidian transmission was initiated by providing colonies with brood (mixture of eggs, larvae, and pupae) from infected S. invicta colonies. Inoculated laboratory colonies of S. invicta had signiÞcantly less brood and adults than control colonies; after 23Ð29 wk, there was at least 88% less brood in the inoculated colonies. Lower egg laying rates, queen weights, and queen survivorship was also documented from infected colonies. Thus, T. solenopsae slowly debilitates an S. invicta queen so that reproductive capacity diminishes and early death results. ArtiÞcial inoculations resulting in infection and spread of T. solenopsae among red imported Þre ant colonies under Þeld conditions was also demonstrated for the 1st time.

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Capture rates of insectary-reared female Aedes albopictus (Skuse), Anopheles quadrimaculatus Say, Culex nigripalpus Theobald, Culex quinquefasciatus Say and Aedes triseriatus (Say) in CDC-type light traps (LT) supplemented with CO2 and using the human landing (HL) collection method were observed in matched-pair experiments in outdoor screened enclosures. Mosquito responses were compared on a catch-per-unit-effort basis using regression analysis with LT and HL as the dependent and independent variables, respectively. The average number of mosquitoes captured in 1 min by LT over a 24-h period was significantly related to the average number captured in 1 min by HL only for Cx. nigripalpus and Cx. quinquefasciatus. Patterns of diel activity indicated by a comparison of the mean response to LT and HL at eight different times in a 24-h period were not superposable for any species. The capture rate efficiency of LT when compared with HL was ≤15% for all mosquitoes except Cx. quinquefasciatus (43%). Statistical models of the relationship between mosquito responses to each collection method indicate that, except for Ae. albopictus, LT and HL capture rates are significantly related only during certain times of the diel period. Estimates of mosquito activity based on observations made between sunset and sunrise were most precise in this regard for An. quadrimaculatus and Cx. nigripalpus, as were those between sunrise and sunset for Cx. quinquefasciatus and Ae. triseriatus.