The West Palearctic species of Rhoptromeris are revised. A total of 11 species are recognised as valid in this region, including four newly described species: Rhoptromeris dichromata sp. nov., Rhoptromeris koponeni sp. nov., Rhoptromeris leptocornis sp. nov. and Rhoptromeris macaronesiensis sp. nov. Eucoila luteicornis Ionescu, 1959 is synonymised with Rhoptromeris heptoma (Hartig, 1840) syn. nov. A checklist of the Holarctic Rhoptromeris is presented and an identification key to the West Palearctic species is provided.

In the search for native Asian parasitoids of Drosophila suzukii, the notorious spotted-wing Drosophila (SWD), an odd new species of Eucoilinae was discovered. Leptopilina lasallei sp. nov. is herein described and diagnosed relative to other eucoilines associated with drosophilid hosts. Morphologically, L. lasallei is somewhat aberrant within Leptopilina; phylogenetically, L. lasallei is sister group to the core Leptopilina. In the process of investigating L. lasallei, a de novo molecular phylogeny of Leptopilina was generated and is included here. The integrated approach used for the characterisation of L. lasallei, and the resulting phylogeny of Leptopilina, produced data useful to select parasitoid species for SWD biological control.

Basidiomes of polypore fungi host many insects. Yet systematic information about insect assemblages from most fungal species is lacking. We studied the insect community associated with the wood-decaying fungus Inonotus radiatus (Sowerby: Fr.) P. Karst. (Hymenochaetales). More specifically, we studied the effect of successional stage and weight of basidiomes, as well as shore exposition (north or south), on species richness and composition, as well as occurrence and abundance of the most abundant fungivores. Basidiomes were collected from riparian forests at five lakes in Sweden. Insects were reared out from the basidiomes in the laboratory. A total of 5645 adult insect individuals of 117 taxa were obtained. Among these, 2782 specimens of 36 taxa use Inonotus radiatus basidiomes as breeding habitat. Eight species of parasitic wasps were new to Sweden. The most abundant fungi- vore was Ennearthron cornutum (Ciidae), which is a generalist breeding in many polypore species. Based on our material and literature, the melandryid beetles Abdera affinis and A. flexuosa seem to be specialists on the order Hymenochaetales. Other fre- quent fungivores were Dorcatoma dresdensis (Ptinidae), and the lepidopterans Archinemapogon yildizae, Nemapogon cloacellus and N. picarellus (Tineidae). The parasitoid community associated with the tineid moths was similar to the community associated with the other polypore species in the order Polyporales. In contrast, the parasitoids associated with Dorcatoma (and/or Abdera) were dif- ferent from the other Polyporales species, suggesting that the fungal host species is more important for these parasitoid species than the beetle host species itself. The most abundant and fre- quent parasitoids were the braconids Diospilus dispar and Colastes fritzeni, which both parasitise Dorcatoma. Species richness was significantly smaller in fresh than in more decayed basidiomes, but species composition did not differ. There was no difference in species composition or richness between north and south shorelines.

The new gregarious parasitoid Meteorus acerbiavorus sp. nov. (Hymenoptera, Braconidae) was reared from the cocoons of Acerbia alpina (Quensel) (Lepidoptera, Arctiidae) in north-western Finnish Lapland. This species belongs to Meteorus rubens (Nees) species group and differs from the most related M. rubens in the following features: the eyes densely setose; the median lobe of the mesoscutum, scutellum, mesopleuron, and the hind coxa entirely or at least partly rugulose-granulate or rugose-areolate and sometimes with granulation; the ovipositor subapically with distinct dorsal node; the ventral borders of the first metasomal tergum weakly separated by narrow space in its basal half; the colour of the body and legs mostly or entirely dark; the fore wing more or less darkened. Phylogenetic relationships among several Meteorus species close to M. rubens including new M. acerbiavorus were investigated based on DNA sequence fragments of the mitochondrial COI and the nuclear 28S rDNA genes. The discussions on the species groups of Meteorus, on distribution of Acerbia alpina in the Holarctic and on its known parasitoids are presented.