Two new species of Oobius(Hymenoptera: Encyrtidae) and their phylogenetic relationship with other congeners from northeastern Asia

AbstractTwo new species of egg parasitoids, Oobius saimaensisYao and Mottern new speciesand Oobius fleischeriYao and Duan new species(Hymenoptera: Encyrtidae), are described from eggs of Agrilus fleischeriObenberger, 1925 (Coleoptera: Buprestidae). Agrilus fleischeriis a phloem-feeding woodborer of poplar (PopulusLinnaeus; Salicaceae) in northeastern China. These two species can be distinguished morphologically as O. fleischerihas five tarsomeres and O. saimaensishas four tarsomeres. Although O. saimaensisis morphologically similar to its sympatric congener O. agriliZhang and Hang, 2005, an important natural enemy of the invasive emerald ash borer, Agrilus planipennisFairmaire, 1888, molecular phylogenetics and morphological data indicate that they are distinct species. Phylogenetic relationships among the new species and other closely related species are also inferred by using DNA sequence data from several ribosomal and mitochondrial genes. In addition, we expand the known distribution of Oobius primorskyensisYao and Duan, 2016 to include South Korea.