蚜虫 ,是同翅目蚜总科的昆虫。它的腹部背侧有一对腹管 ;腹端突出成尾片 ,前翅大 ,前缘有片翅痣。后翅小。蚜虫常发生在杨树、柳树、泡桐、果树的芽或嫩叶上。蚜虫 ,微小 ,体长０．５～２毫米之间 ,是个庞大的家族。１公顷林木上有几十亿头的蚜虫。它呈颗粒状 ,能分泌蜜露 ,所 Aphids, Homoptera aphid total insect. Its abdomen has a pair of abdomen on the dorsal side; the abdomen protrudes into a tail piece, the front wing is big, the front edge has the wing fin. Small hind wings. Aphids often occur in the poplar, willow, paulownia, fruit buds or young leaves. Aphids, tiny, body length between 0.5 to 2 mm, is a huge family. There are billions of aphids on a hectare of trees. It is granular, honey dew can be secreted