Trichogramma wasps (Hymenoptera: Trichogrammatidae) are egg parasitoids commonly employed in augmentative biological control releases against a variety of mainly lepidopteran pests. By exploiting the mechanism by which the endosymbiotic bacterium Wolbachia induces parthenogenesis in this genus, we created a set of completely homozygous Wolbachia‐infected recombinant isofemale lines (RILs), each consisting of a different combination of the genome of two well‐characterized lines of Trichogramma pretiosum Riley. We subsequently use 16 of these RILs to investigate the effect of genetic variation on various measures associated with offspring production under laboratory conditions. Unsurprisingly, substantial differences were found between the RILs in their propensity to parasitize hosts, the number of hosts they parasitize, and the levels of mortality in their offspring. Such measures can be used to choose an optimal line for biological control purposes. A method was also developed to characterize the 16 RILs using their allelic state at five loci. Essentially, this binary system uses high‐resolution melt analysis to resolve identity at each locus, with alleles originating from either the grandmaternal or grandpaternal line, and is such that each RIL can be distinguished from each other RIL by their allelic state at one or more loci. The method facilitates the easy diagnosis of line origin when two or more lines are competing with each other in competition assays, allowing for the design of more complicated tests of parasitoid quality. Future field experiments will determine which genetic line performs best under more realistic biological control conditions. The fact that these lines are infected with parthenogenesis‐inducing Wolbachia will allow for prolonged rearing without appreciable change in their genetic makeup, which should lead to a predictable biological control performance.

The cryptic species that make up the Euwallacea fornicatus species complex can be readily distinguished via their DNA sequences. Until recently, it was believed that the Hawaiian Islands had been invaded by only one of these cryptic species, E. perbrevis (tea shot hole borer; TSHB). However, following the 2016 deposition of a DNA sequence in the public repository GenBank, it became evident that another species, E. fornicatus (polyphagous shot hole borer; PSHB), had been detected in macadamia orchards on Hawaiʻi Island (the Big Island). We surveyed the two most-populous islands of Hawaiʻi, Big Island and Oʻahu, and herein confirm that populations of TSHB and PSHB are established on both. Beetles were collected using a variety of techniques in macadamia orchards and natural areas. Individual specimens were identified to species using a high-resolution melt assay, described herein and validated by subsequent sequencing of specimens. It remains unclear how long each species has been present in the state, and while neither is currently recognized as causing serious economic or ecological damage in Hawaiʻi, the similarity of the newly-confirmed PSHB population to other damaging invasive PSHB populations around the world is discussed. Although the invasive PSHB populations in Hawaiʻi and California likely have different geographic origins within the beetle’s native range, they share identical Fusarium and Graphium fungal symbionts, neither of which have been isolated from PSHB in that native range.