Two New Chalcid Wasps (Hymenoptera: Eulophidae and Megastigmidae) Are Parasitoids of Ophelimus bipolaris (Hymenoptera: Eulophidae) on Eucalyptus in China

Two new species, Aprostocetus eucalyptus Zheng & Yefremova sp. nov. (Hymenoptera: Eulophidae) and Megastigmus bipolaris Zheng & Yefremova sp. nov. (Hymenoptera: Megastigmidae), were discovered on populations of the invasive gall wasp Ophelimus bipolaris (Hymenoptera: Eulophidae) infesting Eucalyptus in Guangxi, China. An integrative taxonomic approach combining morphological characterization and 28S rRNA-based phylogenetic analysis was used for species identification and classification. Detailed morphological descriptions, illustrations, and an identification key for both sexes are provided. Field parasitism data confirm their potential as native natural enemies, supporting their utility for the biological control of this economically important pest.