Key scale insects (Hemiptera: Coccoidea) of high economic importance in a Mediterranean area: host plants, bio-ecological characteristics, natural enemies and pest management strategies.

Key scale insects that have long been considered as having high economic importance in Tunisia and for which severalresearch studies and pest management programs have been undertaken include the mealybug species Planococcus ficus(Signoret) and Planococcus citri Risso, the soft scale Saissetia oleae (Olivier) and the armoured scale Parlatoria ziziphi(Lucas). The host plants, bio-ecological aspects, auxiliary fauna of each of the aforementioned species as well as therelated economic losses and pest management strategies adopted are explored and discussed. Among these species,P. ficus is considered herein as the most economically important in Tunisia. Still, the present contribution constitutesthe first review article on key scale insects infesting plants in the South Mediterranean Maghreb area.