A survey of scale insects (Hemiptera: Coccoidea) occurring on olives in Tunisia

A survey performed in 2009 within 52 Tunisian olive groves, located in 17 different olive-growing sites, revealed the occurrence of six scale insects on olives. The identified species were: the armoured scales Aspidiotus nerii Bouché, Lepidosaphes ulmi (L.), and Parlatoria oleae (Colvée), the soft scales Saissetia oleae (Olivier) and Filippia follicularis (Targioni Tozzetti) and the mealybug species Peliococcus cycliger (Leonardi). The soft scale F. follicularis is a new record for the Tunisian insect fauna. A mong these species, S. oleae was the predominant scale insect occurring throughout olive groves of northeastern Tunisia, whereas the mealybug P. cycliger was by far the most abundant species within olives groves of the Northwest region of Tunisia. However, P. oleae was the least abundant species, being present in only one olive-growing site in northeastern Tunisia. L arvae of the noctuid moth Eublemma scitula (Rambur) were reported feeding on S. oleae and the coccinellid Chilocorus bipustulatus L . was found feeding on both S. oleae and A. nerii. The two hymenopteran species Scutellista cyanea Motschulsky and Metaphycus spp. were recorded as the main parasitoids of S. oleae.