Toxares deltiger (Haliday) (Hymenoptera: Aphidiidae) parasiting the cereal aphid, Metopolophium dirhodum (Walker) (Hemiptera: Aphididae), in southern England: a new host-parasitoid record

Abstract

AbstractSixty-seven per cent of parasitoid mummies which developed from Metopolophium dirhodum (Wlk.) collected in wheat fields at Rothamsted, southern England, in 1979 were of Toxares deltiger (Hal.), a species previously unrecorded from cereal aphids. T. deltiger formed only 1% of samples when parasitoid mummies were collected directly from cereals in the field. Laboratory observations of the parasitoid indicate that affected aphids probably leave the host-plant prior to death and mummy formation.