人们熟知的蝇、蚊属双翅目。估计世界上这一个目的昆虫超过15万种,不过已知名的仅9万种,也算很大的一个类群。其主要特点是只有一对发达的前翅,后翅退化为很小的平衡棍。其幼虫形态为蛆型,头退化而缩入体内。其中一类重要的天敌称为食蚜蝇(见附图)。食蚜蝇的幼虫是控制农、林、果、菜蚜虫的好卫土。几乎所有蚜虫它们都可以捕食。此外还能捕食介壳虫、粉虱、叶 People are familiar with the fly, mosquito diptera. It is estimated that there are more than 150,000 species of insects in this world for one purpose, but only 90,000 species are well known, and a large group. Its main feature is only a pair of developed forewing, hind wings degenerated into small balance stick. Its larvae form maggot type, head degeneration and shrink into the body. One of the most important natural enemies is called the hoverfly (see photo). The larva of the hoverfly is a good source of soil for the control of agricultural, forestry, fruit and vegetable aphids. Almost all aphids are prey on them. In addition can also prey on scale insects, whitefly, leaf