The taxonomy of the Nearctic species of Pediobius (Hymenoptera: Eulophidae), especially Canadian and Alaskan forms.
Thirty-two species of Pediobius are reviewed, 9 newly noted from both Europe and North America. Special attention is paid to species occurring in Canada and Alaska and to records from the Canadian Forest Insect Survey. A key to the Nearctic species is presented, based on characters of the adult males and females. A primary and secondary host-parasite list for Nearctic species is provided and includes spiders and many insects (Lepidoptera, Coleoptera, Hymenoptera and Diptera) and some plants. The accounts of species include information on hosts and their food-plants. Some new species are described and some taxonomic changes are proposed. Among these, P. tarsalis and P. ashmeadi are considered to be synonyms of P. crassicornis, P. lithocolletidis a synonym of P. albipes, P. sexdentatus a synonym of P. facialis, and P. utahensis a synonym of P. eubius.