Abul-Nasr, S., Swailem, S.M., & Ahmed, N.M. 1975 Population studies on the Eyptian citrus black scale insect Chrysomphalus ficus Ashmead in different regions (Hemiptera, Homop.: Diaspididae).. Agricultural Research Review 53: 127-137.

Notes: The Egyptian black scale insect Chrysomphalus ficus Ashmead is one of the most injurious pests to orange trees in Egypt. The Egyptian black scale insect increases during late summer in Gharbeia and during winter months in Menofeia, Qalyobeia and Giza. The population reaches its lowest level during July in four governates. The insects settle on both surfaces of the navel orange leaves but with females (either nymphs or adults) mainly on the lower surfaces and males on the upper surfaces. During the period of high population, the quick reproduction of the insect exceeds the activity of parasitism.