Predator of Aphids
Aphidoletes is a gall midge that occurs naturally in Europe, North America and Asia. Contrary to some other gall midge species, Aphidoletes does not cause damage by forming galls on leaves. The adult is about 2.5 mm long, with long legs and a slender body. Males have long antennae that are bent backwards and are covered with long hairs, while females have shorter, darker antennae.
Aphidoletes is mainly active at night. After sunset the female deposits her eggs in aphid colonies. The number of eggs depends on the climate and the nutrition the gall midge has had as a larva and as an adult, but it usually amounts up to more than hundred. After 2-3 days, eggs hatch to larvae and almost immediately start sucking aphids empty around them. There are 3 larval stages. Initially the larva is transparent orange, but later on it turns, depending on its food, orange, red, brown or grey. After a life of 7-14 days (at 21°C or 69.8°F) as a larva, it pupates in the ground. It makes an oval, brown cocoon covered with sand grains, aphid skins and excrements. 10 to 14 days later an adult gall midge emerges.
Since the larva looks for its prey in the surrounding 6 cm of its birth place, the female gall midge prefers to deposit her eggs in sufficiently big aphid colonies. One larva needs minimum 5 aphids for its development, but it will kill more if there are more available. The larva first injects a poison in the aphid, which paralyses the aphid and dissolves its body contents in 10 minutes. Aphidoletes aphidimyza is known to eat at least 70 different aphid species. The adult feeds on honeydew. The adult life span is 7-10 days, but it might be shorter at lack of honeydew. Dry conditions also shorten life span. Mating usually occurs after sunset or before sunrise or on a fresh and shady place low in the crop.
In nature the pupa enters diapause from end September till May (in temperate regions). In the greenhouse this diapause is interrupted by higher temperatures from early spring.
SKU: APH1K .