Target pest: Pseudococcus viburni (Hemiptera: Pseudococcidae) = Pseudococcus affinis, Pseudococcus obscurus, obscure mealybug
Agent introduced: Exochomus nigromaculatus (Coleoptera: Coccinellidae)
Cameron et al. (1989) - between February 1924 and December 1926, five shipments of assorted mealybug [Pseudococcidae] natural enemies arrived in New Zealand from California, USA. The consignments contained natural enemies that were effective against mealybug pests (especially Pseudococcus citri) in California at the time. All imported individuals were placed in an insectary in Nelson, but none survived. Many, and sometimes all, were dead on arrival in New Zealand. There were no releases from these consignments. Exochomus nigromaculatus was included in one of these consignments, arriving on 9 June 1925.
Cameron et al. (1989) - not released.
Cameron PJ, Hill RL, Bain J, Thomas WP (1989). A Review of Biological Control of Invertebrate Pests and Weeds in New Zealand 1874-1987. Technical Communication No 10. CAB International Institute of Biological Control. DSIR Entomology Division. 424p.