Mosquito
Mosquitoes of the genus "Toxorhynchites" never drink blood. This genus includes the largest extant mosquitoes, the larvae of which prey on the larvae of other mosquitoes. These mosquito eaters have been used in the past as mosquito control agents, with varying success.
List of largest insects
Giant shield mantids of the genus "Rhombodera" can reach lengths of nearly and are more robust than comparably sized mantids of other genera ("Tenodera", "Hierodula", "Sphodromantis" and "Plistospilota".) Some larger species have been known to capture and consume frogs, lizards, mice, small birds, and even snakes. Giant Stick Mantids of the genus "Toxodera" and "Solygia" can reach lengths of 20 cm, but are more gracile in build than other large mantids.