Xie, Y.P., & Xue, J.L. 2005 [Ultra-morphology and chemical composition of waxes secreted by two wax scale insects, Ceroplastes ceriferus (Fabricius) and C. japonicus Green (Homoptera: Coccidae).]. Acta Entomologica Sinica 48(6): 837-848.

Notes: The ultra-morphology and chemical composition of waxes secreted by the scale insects, Ceroplastes ceriferus (Fabricius) and C. japonicus Green (Homoptera: Coccidae) were studied with the techniques of scanning electron microscope (SEM) and gas chromatography/ mass spectrometry (GC/MS). The results indicate that the two wax scale insects have a similar waxy secretion and wax test forming process. The scale insects in their first and second instars secreted dry wax that formed a star-shaped test. Every wax horn around the margin of the test consists of two segments. This corresponds to the two developmental instars. Furthermore, each of the two segments of the wax horn included many sub-segments. Meanwhile, wax accumulated into a cap-like structure with many layers on the dorsal region of the body. It was believed that some kind of rhythm existed in the secretion of wax. A lot of striate punctures formed wax glands that are not usually found with on slide specimens of wax scale insects observed under light microscopy. As the scales developed into the 3rd instar and adult stage, the wax secretion changed into "wet state" and formed a waxy test in tortoise shell shape. The wax glands on the dorsal surface mainly are trilocular and quadrilocular pores. Dense wax pores arranged in longitudinal strips were also found on the anal plates. The main chemical composition of the wax secretions of the two scale insects were determined with GC/MS by the esterification and unesterification. For C. ceriferus, 14 and 14 compounds were determined from its wax secretion with the two methods respectively; while 10 and 25 compounds were determined respectively from the wax secretion of C. japonicus. The main composition of the wax secretions include a series of long chain saturated and unsaturated hydrocarbons, fatty acids, fatty alcohol, esters, and some compounds with ring structures of multi-, macro-, or heterocyclic ring. Their biological functions were discussed.