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
The beetles are the largest order of organisms on earth, with about 350,000 species so far identified. The most massive species belong to the genera "Goliathus", "Megasoma", "Chalcosoma" and "Titanus". The longest species is the Hercules beetle, "Dynastes hercules", with a maximum overall length of at least including the very long pronotal horn.