The plant pests related to scale insects occur worldwide. There are about 70 species with corresponding host plants, varying in size (from 2 to 8 mm in length), shape (round or oval) and colour (e.g. yellow, bronze, red or light brown). There are several species specialised in vines, mainly found in North and South America and South Africa. The most common species is called Margarodes prieskaensis, others are Margarodes capensis, Margarodes greeni, Margarodes trimeni, Margarodes vitis and Margarodes vredendalensis. Mating by winged male and female insects takes place above ground. The female can produce more than 1,000 eggs in several egg deposits, which are laid underground. The wart-like nymphs hatching from these eggs in the form of a cyst (left picture) feed on plant roots in a similar way to phylloxera and can destroy a vine within a few years. After pupation, they develop into winged sex animals (right picture). Grafting is not a viable option, as no resistant vine species are known. See a list of all pests and diseases under vine enemies.
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