Hover flies
Hover flies belong to the family Syrphidae. They are also known as Syrphid flies or Flower flies. Larvae of many species of hover flies are predaceous on aphids, small caterpillars and thrips.
Hover fly larvae eating aphids
Adult hover fly
Description and life cycle
Adult hover flies are often found near flowers and usually do a lot of hovering. They feed on nectar and pollen. Many species are brightly colored, with yellow and black stripes and often they resemble bees or wasps.
Females lay single eggs on the plants near aphid populations. Each female can lay several hundred eggs. The eggs hatch after 2 or 3 days. The larvae are small maggots that feed voraciously on aphids. In its life span one larva can eat up to 400 aphids. The larval stage has 3 instars which together take about 2 weeks to develop into a pupa.
Hover fly larvae are voracious predators that can eat many
aphids.
Conservation
Hover flies are easily killed by pesticides. Therefore pesticide applications should be avoided when possible.
Adult hover flies feed on flowering plants. Planting flowering plants near the field or between the crop plants will attract adult flies and increase the possibility that they lay their eggs in the field.