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The recent introduction of new pest species in Morocco and other Mediterranean countries has caused serious problems for many crops. Among the newly introduced pests in Morocco, we have found the scale insects Dactylopius opuntiae (Cockerell) (Hemiptera: Dactylopiidae), Phenacoccus solenopsis (Tinsley), and Phenacoccus peruvianus (Granara de Willink & Szumik) (Hemiptera: Pseudococcidae). To control these scale pests, the parasitism potential of four parasitoid species: Aprostocetus mymaridis (Eulophidae: Hymenoptera), Anagyrus aligarhensis, Anagyrus sp., and Leptomastix epona (Encyrtidae: Hymenoptera) were investigated under laboratory (at 26 ± 2 °C, 60 ± 10% RH) and field conditions. Under laboratory conditions, the experiments were conducted in no choice feeding tests (only third nymphal instars or pre-ovipositing adult females of each scale pest were offered at a time) and choice feeding tests (third nymphal instars and pre-ovipositing adult females were offered simultaneously). We observed that none of the parasitoids tested parasitized D. opuntiae. In both laboratory experimental tests (no choice and free choice tests), A. mymaridis parasitized the highest mean number of third instar nymph and adult female of P. solenopsis (16.90–25.10, and 27.70–29.60, respectively), and L. epona found parasitized the highest mean number of P. peruvianus third instar nymph and adult female (17.70–19.90, and 20.10–24.10, respectively). Aprostocetus mymaridis was found practically suitable for the biological control program of P. solenopsis as they showed a higher level of parasitization under laboratory under field conditions (63.34%). Leptomastix epona seems to be the most successful parasitoid against P. peruvianus under field conditions (67.00%) compared to the other parasitoids tested. [ABSTRACT FROM AUTHOR]

Phenacoccus peruvianus Granara de Willink (Hemiptera: Pseudococcidae) is a new invasive mealybug that causes important damages in ornamental plants in urban landscapes and nurseries in Southern Europe. Recently, a new species of genus Acerophagus Smith (Hymenoptera: Encyrtidae) has been recorded as the main parasitoid of P. peruvianus in Spain, displacing the native parasitoid Leptomastix epona Walker (Hymenoptera: Encyrtidae). In this work, we have determined some traits of the reproductive and feeding strategies of Acerophagus sp.: fecundity, immature developmental time, host instar suitability, and preference when parasitizing P. peruvianus, and the effect of natural occurring sugar sources on adult longevity. Acerophagus sp. egg load reached its maximum when it was 5 days old. Second and third nymphal instars and adults were suitable for parasitism and immature development (efficient encapsulation was low). Immature development lasted between 20 and 22 days. Acerophagus sp. developed as a solitary parasitoid in the second instar and as a gregarious parasitoid in older instars (2-4 parasitoids per host). All the emerged offspring were females. Acerophagus sp. always preferred older instars when different host instars were available. Finally, adults lived more than 20 days when fed on honey, but they lived fewer than 3 days when fed on naturally occurring sugar sources (host honeydew and host plant flowers, Bougainvillea glabra). The consequences of these characteristics on biological control and parasitoid rearing are discussed. [ABSTRACT FROM AUTHOR]