---

The present work is devoted to achieve these objectives: Survey of the aquatic predaceous insects upon mosquito larvae and pupae. Study the life history and feeding habits of mosquito predator, Rhantus elevatus (Coleoptera, Dytiscidae) when reared on mosquito, Culex pipiens (Culicidae, Diptera) and Evaluation the effect of Bacillus on both C. pipiens larvae and the larvae and adults of its predator, R. elevatus. Ten species of predatory insects were found associated with mosquito larvae and pupae. These predatory insects are belonging to orders, Heteroptera, Coleoptera, and Odonata. This study showed that the mosquito predator, R. elevatus considered one of the most important agents to control larvae and pupae of mosquitoes. According to regression analysis between P: p ratios of R elevatus (larvae and adults) and reduction percentage of larvae and pupae of mosquito, there were negatively high relationship of predator, which means that the reduction rate was increased with lower P: p ratios and vice versa. The results also indicated that the effect of Bacillus showed high mortality against mosquito larvae and there was no significant effect on larvae and adults of R. elevatus.

---

Ahmed Rashed Ahmed, Assistant Professor. Economic Entomology Dept., Fac. of Agric., Mansoura Univ.,Egypt. Awards:Annually received Undergraduate Student Awards (monthly financial support from Mansoura University) for achieving high standing. Mansoura University award for the best Ph. D. thesis,2010/2011.

---