Psyllids (Jumping plant lice, jumping plant louse)


Jumping plant lice or psyllids form the family Psyllidae of small plant-feeding insects that tend to be very host-specific, i.e. each plant-louse species only feeds on one plant species (monophagous) or feeds on a few closely related plants (oligophagous). Sometimes called jumping plant lice, psyllids feed on a variety of plants including most fruit trees and small fruits as well as tomato and potato. Both adults and nymphs feed by piercing the leaf surface and extracting cell sap. This causes foliage (especially the upper leaves) to turn yellow, curl and eventually die. Honeydew secreted by the psyllids encourages the growth of dark sooty molds. Many species transmit disease-carrying viruses. Adults (1/10 inch long) are reddish brown in color with transparent wings and strong jumping legs. They are very active and will hop or fly away when disturbed. Nymphs are flat and elliptical in shape, almost scale-like. They are less active than adults and are most numerous on the undersides of leaves. Newly hatched nymphs are yellowish in color but turn green as they mature.