Severe infestations can cause defoliation. These pests belong to the class Insecta , order Homoptera , families Diaspididae, Coccidae and Pseudococcidae. They are a major pest to plant crops. Males begin much as females but pupate at the end of the developmental period. Adult males appear as small two-winged flies without mouth parts.
Females are wingless and usually immobile.
All are covered with a waxy or resinous material. Soft scales and mealybugs secrete honeydew. Unlike the other two, armored scales produce a hardened covering and lose their legs. The others may be immobile at some period but may move when under stress. Several faintly marked ridges radiate from the origin of the scale.