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.
Mosquito
Some species of blood-sucking flies, such as many of the Ceratopogonidae, will attack large, live insects and suck their haemolymph and others, such as the so-called "jackal flies" (Milichiidae), will attack the recently dead prey of say, crab spiders (Thomisidae). In 1969 it was reported that some species of anautogenous mosquitoes would feed on the haemolymph of caterpillars. Other observations include mosquitoes feeding on cicadas and mantids. In 2014 it was shown that malaria-transmitting mosquitoes actively seek out some species of caterpillars and feed on their haemolymph, and do so to the caterpillar's apparent physical detriment.