Aphidoletes aphidimyza larvae are voracious native predators of over 60 species of aphids. The larvae are legless maggots about 3 mm long, and orange in color which make them easy to spot in foliage. Adults are small midges resembling mosquitos that are nomadic (they will seek out heavy aphid populations to lay eggs near) and can be hard to find.
Aphidoletes are used to control aphids indoors in commercial greenhouses and interior plantscapes as well as outdoors in orchards, shade trees, roses, and home gardens. The larvae need to burrow into damp soil, peat moss, sawdust or other growth media to pupate. In greenhouses with bare plastic or concrete floors, survival will be low unless such organic materials are provided. Adding a very thin layer (1/8 inch) of sand, sawdust or other organic materials under the leaf zones of plants will improve cycling of Aphidoletes. It may be necessary to control ants in conservatories and around outdoor trees (use ant bait) because they can protect aphid colonies by removing predator larvae.
The complete life cycle takes 24 days at 70°F (21°C), but can vary depending on temperature and availability of prey. Sex rations may vary, but there are usually more (60%) females. Females lay eggs on leaves beside aphids (150-200 in a lifetime), which are shiny orange ovals, less than 0.3 mm long.
At optimal temperatures, the eggs will hatch in 2-3 days and the tiny, legless larvae crawl along the leaf in search of aphids. They feed by biting aphids and paralyzing them with a toxin before sucking out the aphid body fluids. They feed for 7-10 days and can kill up to 50 aphids per day
0.05-0.1+ midge per square foot of crop canopy.
Aphidoletes is sent as pupae (cocoons) in moist vermiculite or sand. For control of cotton/melon aphid, which reproduces very quickly, Aphidoletes should be used along with Aphidius parasitic wasps.