Morphological Study of the Soft Scale Insect Protopulvinaria pyriformis (Cockerell, 1894) (Hemiptera: Coccidae) Using Scanning Electron Microscopy

Pyriform scale, Protopulvinaria pyriformis (Cockerell, 1894) is an exotic insect pest. This pest represents a serious pest of fruit trees and ornamental plants in many parts of the world. This insect pest infests many host species belonging to many plant families. The entire life cycle is spent on the lower leaf surface and few individuals were also observed on the upper parts of the leaf surface and it is estimated that the fecundity of this scale insect reaches about 200 eggs per female. The major damage from excretion large quantity of honeydew, which support the growth of sooty mould fungus and leads to defoliation. The present study deals with morphological description for pyriform scale by measuring the length and width of the different stages of nymph and adult female, since no males have been discovered for this insect and it reproduces by parthenogenesis. Also, some morphological characters of the adult female of this soft scale insect were studied by using a scanning electron microscope and photographing the ultrastructure of some parts such as, antennae, legs, marginal seta, bilocular pore, anal plate and wax producing pores. Results revealed that antennae consist of 8 segments, multilocular pores scattered around vulva and in transverse rows on abdomen.