In the Old World, this members of this family are found on oaks in the genus Quercus and trees in the genera Shorea and Dipterocarpus in the family Dipterocarpaceae. The New World species are parasites of palms.
Most scales in this family have four female instars and five male instars. Members of the genus Gallacoccus have only three female instars however. The females form galls which are often quite ornate. In some species the first instars seem to act as soldiers and attempt to guard the gall. Adult males appear to develop inside the female galls.