Very small insects with a few millimeters in size, which is a suborder of the large group of plant lice (such as, for example aphids and cicadas ). The females, which are usually wingless in contrast to the males, infest leaves, fruits and bark of various plants as well vines, They occur mainly in warmer areas, in Central Europe especially the Napfschildläuse (Coccidae). They have piercing-sucking mouthparts with piercing bristles which are used to pierce food by piercing vegetable tissue. This leads to growth disorders, discoloration, wilting phenomena to death. The animals divorced as excrement and the honeydew which is often colonized by black sooty mushrooms. The development of insects takes place from the egg up to five larval stages and a nymph to the sexual animals, which then have the typical protective cover (shield). The species Planococcus and Pseudococcus also transmit virus, those who Leaf roll disease cause cork bark disease (see below Rugose Wood Complex ).
For the viticulture of importance is above all the "Rebenschildlaus" (Parthenolecanium corni), which is also under "Plum-Napfschildlaus" or "ordinary Napfschildlaus" admits. This affects plums, apricots, spiny and currants and also vines, Hibernation takes place as a second larval stage on branches and shoots as well as in the soil. With the expulsion the larvae migrate to the young shoots where they develop into about six millimeters females towards the end of May. At the same time, the back thickens and solidifies to a high-vaulted, brownish and painted shield, under which there are up to 3,000 eggs (hence the name). The larvae hatch towards the end of June, migrate to the underside of the leaves and suck on it. Mostly there is only one generation. The species "Wollige Rebenschildlaus" (because of salmon-red eggs also "Blutlaus") also attacks the roots. There are other species as well Rebenschmierlaus, Natural enemies are lacewings. ladybug and parasitic wasps some of which are deliberately imposed. See also below Vine enemies,