Among insects, Hymenoptera (primarily bees, wasps and ants) is probably the most speciose and thus successful animal taxon worldwide. Their biodiversity and specimen numbers are unsurpassed, which is one of the reasons why insects play a prominent role (mainly, but not only) in terrestrial ecosystems. Pollination, pest control and food source are just a few examples of the ecosystem services these arthropods provide to the planet. However, most animal species on earth are insects, it is estimated that up to 80 % of hymenopteran species diversity is still unknown to science. At the same time, extinction rates of all taxonomic kingdoms are at their highest due to human impact on the planet. The increasing disappearance of species makes it all the more urgent for taxonomists to describe unknown species more quickly. This endeavor is particularly difficult in remote areas and with very diverse, often small, cryptic taxa, the so-called "Dark Taxa" (DT). With these groups, even identifying the genus is often a significant hurdle for a “non-specialist”. And while the diversity of (not only hymenopteran) insect species is greatest in the tropics, thousands of species are probably still undescribed even in a supposedly well-researched western country like Germany. The German Barcode of Life (GBOL) project aims to catalog as many animal species as possible in Germany by obtaining the sequence of the mitochondrial CO1 gene, which is used as a barcode (the so-called Barcode Index Number (BIN)) or proxy to genetically distinguish between different taxa. The third phase of the GBOL project, the GBOL III: Dark Taxa project, was launched to tackle multiple Dark Taxa, assess their diversity, and test and apply new integrative taxonomic approaches to achieve an efficient increase in knowledge. The parasitoid wasp families Diapriidae and Ismaridae are the subject of this work. This species-rich but highly understudied group is treated with an integrative taxonomic approach.