Branco, M., Departamento de Engenharia Florestal, Instituto Superior de Agronomia, 1349-017 Lisboa, Portugal
Franco, J.C., Departamento de Protecção Das Plantas e de Fitoecologia, Instituto Superior de Agronomia, 1349-017 Lisboa, Portugal
Dunkelblum, E., Department of Entomology, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
Assael, F., Department of Entomology, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
Protasov, A., Department of Entomology, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
Ofer, D., Department of Entomology, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel
Mendel, Z., Department of Entomology, Agricultural Research Organization, Volcani Center, Bet Dagan, 50250, Israel

The attraction of several adult predators, genera Elatophilus, Hemerobius and Sympherobius, to the sex pheromones of pine bast scales, Matsucoccus Cockerell, has already been demonstrated. Here, the hypothesis that the larvae of these predators are similarly attracted to the host prey sex pheromone is tested. The response of predators was tested in field trials using pine tree arenas baited with the sex pheromones of M. josephi Bodenheimer & Harpaz, M. feytaudi Ducasse and M. matsumurae Kuwana. Experiments were conducted in Israel in stands of Pinus halepensis infested by M. josephi and in Portugal in stands of P. pinaster infested by M. feytaudi, respectively. The selectivity of larvae for the three sex pheromones was tested in Petri dish arenas in the laboratory. In the field, the larval stages exhibited similar modes of attraction to those of the conspecific adults: Elatophilus hebraicus Pericart in Aleppo pine forest, E. crassicornis Reuter and Hemerobius stigma Stephens in the maritime pine forests. Laboratory choice tests confirmed the kairomonal selectivity of larvae. Both forest and laboratory tests demonstrated the response of a coccinellid of the genus Rhyzobius to the sex pheromones of M. feytaudi and M. matsumurae. A unique chemical communication system among several taxa of predators of Matsucoccus spp. was highlighted that may be attributed to their coevolution on a geological time scale. © CAB International, 2006.