Insects with sucking mouth parts
Some insects damage plants by piercing the outer layer of plant tissue and sucking the juices from within. Their long needle-like beaks usually are jointed, and they may point forward, upward or downward. When not in use, their beaks are usually laid back on the breast between the front legs. These insects are immune to poison dusts or sprays because they pierce through the poisoned layer to draw their nutrients from the plant. They are controlled by contact poisons – poisons that come into direct contact with their bodies.