Parlatoria ziziphi (Lucas)
Common name: Black parlatoria scale.
Geographical distribution: Many tropical and subtropical regions of the world, in the Middle East known from Egypt and Turkey. CIE Map #186, 1964.
Economic importance: This scale is the most important pest of citrus in Upper Egypt. Its feeding kills branches and seriously affects yield as well as deforming fruits. In addition, the presence of the scale’s conspicuous shields on the fruit (from which they are hard to remove) greatly detracts from its market value.
Morphology: The dorsal macroducts are two-barred, the orifices of the marginal macroducts on the pygidium are surrounded by sclerotized rings, and the body is oval. The scale has no macroducts within the frame formed by the perivulvar pores (20-30 on each side), by the weakly notched external margins of the similar pygidial lobes, and by having the fourth lobe in the form of a conical projection. The anus is located between the posterior groups of perivulvar pores. There are no duct tubercles on the prosoma, which bears a prominent ear-like lobe placed opposite the anterior spiracles. The body of all stages (including the winged males) and of the eggs is violet, except shortly after molting, when the body is white. The female shield is pear shaped, consisting mostly of the black second-stage exuvium with two distinct ridges, and a whitish, caudal fringe, secreted by the female. The dorsal exuvium of the first stage is dark, placed at one end of the female’s shield, from which it slightly protrudes. The male shield is whitish, elongated, bearing at one end the large, dark exuvium of the crawler (1st-instar nymph).
Life cycle: The pest raises 4-5 overlapping generations. Although leaves are the preferred settling sites, the scale also settles and feeds on fruit and branches.
Coll, M. and Abd-Rabou, S. 1998. Effect of oil emulsion sprays on parasitoids of the black parlatoria, Parlatoria ziziphi in grapefruit. BioControl: 43: 29-37.
MEDJDOUB, Y. 2014. Bio-écologie de la cochenille noire Parlatoria ziziphi (Homoptera, Diaspididae) sur les agrumes dans la station d’El Fhoul à Tlemcen. Thesis, Université d’Abou-Bekrbelkaid, Tlemcen, Algiers.