Pachyneuron (Hymenoptera: Pteromalidae) and its relationship to ladybirds (Coleoptera: Coccinellidae): new data from Iran and review of the literature.

Species of Pachyneuron Walker are most often reported as hyperparasitoids of aphids, coccids and psyllids (Hemiptera: Sternorrhyncha). On the other hand, quite many reports concern hyperparasitism in the predators of Sternorrhyncha, mainly ladybird beetles. In this paper we report on the association of Pachyneuron muscarum (L.) with a ladybird Hippodamia variegata (Goeze) that was detected during a survey of parasitoids of ladybird larvae in Kermanshah (Iran). We bred P. muscarum wasps from two field collected H. variegata larvae. A single male P. muscarum emerged from one larva, parasitized by a primary parasitoid of the genus Homalotylus Mayr (Hymenoptera: Encyrtidae), and a female P. muscarum emerged from the other larva, parasitized by a parasitoid other than Homalotylus. Previously, P. muscarum was reported from Iran in association with several species of coccids and psyllids, as well as predatory lacewing (Neuroptera: Chrysopidae) and ladybird larvae. A worldwide literature review indicates that at least eight species of Pachyneuron have been reported as hyperparasitoids of ladybird larvae. It may be thus concluded that some Pachyneuron species, being principally hyperparasitoids of Sternorrhyncha, can also hyperparasitize Sternorrhyncha-preying ladybird larvae. [ABSTRACT FROM AUTHOR]