aphid Also called a greenfly, a sap-feeding insect of the family Aphididae, order Homoptera. Aphids have needle-like mouthparts with which they piece the plant tissue, the pressure within this forcing the sap into the insect's gut. Because of the damage caused by their feeding and because many species carry harmful viruses, aphids are one of the world's great crop pests. The life cycle is complex, so that within a species there may be at any one time a diversity of forms: winged and wingless, reproducing sexually or by parthenogenesis. Aphids excrete a substance known as honeydew, which is a major food source for ants and other insects. Related category • ZOOLOGY Also on this site: Encyclopedia of Alternative Energy & Sustainable Living Encyclopedia of History Transport Concepts & Designs (partner site) |