A STUDY OF TWO PLAGIOMERUS SPECIES (HYMENOPTERA: ENCYRTIDAE) PARASITISING DIASPIDID SCALES (COCCOIDEA) IN GLASSHOUSES IN FRANCE

Abstract

A STUDY OF TWO PLAGIOMERUS SPECIES (HYMENOPTERA: ENCYRTIDAE) PARASITISING DIASPIDID SCALES (COCCOIDEA) IN GLASSHOUSES IN FRANCE.

Plagiomerus diaspidis Crawford was imported from Tenerife (Canary Islands, Spain) and released experimentally as a biological control agent against Diaspis echinocacti (Bouché) (Hemiptera, Diaspididae) within a cactus glasshouse in south-eastern France but it failed to provide control, apparently due to very weak powers of dispersal. A second undescribed Plagiomerus was found in a wet tropical greenhouse in the same region of France and was thought to be a potential biocontrol agent of Diaspididae. It was found to parasitise the three Diaspis species (D. boisduvalii Signoret, D. coccois (Lichtenstein) and D. bromeliae (Kerner)) present in the greenhouse, although it failed to control them. Both parasitoid species reproduced by thelytokous parthenogenesis.

Key words: development, Boisduval scale, preferred environments, USA, Mexico, Azerbaidjan, Opuntia, Strelitzia, Calanthe, palm.