Hoverflies

Hoverflies, also called flower flies or syrphids, make up the insect family Syrphidae. As their common name suggests, they are often seen hovering or nectaring at flowers; the adults of many species feed mainly on nectar and pollen, while the larvae (maggots) eat a wide range of foods. In some species, the larvae are saprotrophs, specifically detritivores, eating decaying plant and animal matter in the soil or in ponds and streams. In other species, the larvae are insectivores, preying on aphids, thrips, and other plant-sucking insects.

larvae of certain species of hoverflies

Wikimedia list article