The families Pseudococcidae (mealybugs) and Monophlebidae include small scale insects (Coccoidea: Hemiptera) that suck out plant sap. The bodies of young instars and adult females are covered with a wax secretion, whereas adult males carry a pair of small wings. Feeding by these pests can cause premature leaf, flower, and fruit drop, reduce plant vigour and discolour tissues. In addition, they secrete honeydew upon which sooty-mould fungi grow, reducing photosynthesis and the market value of the product. Six species of Pseudococcidae, namely Planococcus citri (Risso), Pseudococcus cryptus Hempel, Ps. longispinus (Targioni Tozzetti), Ps. calceolariae (Maskell), Ps. viburni (Signoret) and Nipaecoccus viridis (Newstead) are economic pests of citrus in the Mediterranean area, along with Icerya purchasi Maskell, in the family Monophlebidae.