The new combination of Ganaspis brasiliensis (Ihering, 1905) is proposed, and the species is redescribed from historical specimens taken in the Neotropical Region as well as more recent specimens reared from Drosophila suzukii Matsumura, 1931 in South Korea. Drosophila suzukii, otherwise known as the spotted-wing Drosophila, is a major pest of soft fruits the world over, and the search for effective natural enemies of this fly are ongoing. Though not parasitoids of D. suzukii, we also propose the following new combinations: Dieucoila brasiliensis (Kieffer, 1909), new combination, and Dieucoila brasiliana (Weld, 1952), new combination. After summarizing all known species of Eucoilinae with the specific epithet ‘brasiliensis’, we encourage future researchers to avoid this name in order prevent nomenclatural confusion.

Garudella, a remarkable new genus of eucoiline wasp is described from Thailand, Laos, and the Republic of Congo. Four new species of Garudella are described as well: G. acothonaspis, G. afrotropica, G. algo, and G. alicae. Several autapomorphies distinguish this genus from other eucoiline genera: a distinctly protracted and broadened pronotal plate; a massive, posteriorly protruding prop- odeum; reduced posterior rim of metapleuron; reduced scutellar foveae and lack of lateral bar “windows”; and a generally reduced scutellar plate. In addition, the posterior of the head has a distinctly curved occipital impression, resulting in the cuticle surrounding the foramen magnum to be extruded into a neck-like process. The biology of Garudella is unknown, but based on phylogenetic inference from morphology, the presumed host could be a cyclorrhaphous Diptera in a saprophagous environment.

The eucoiline genus Zaeucoila Ashmead is revised. Following a re- evaluation combining previously published phylogenetic data and new specimens, Agrostocynips D ́ıaz is synonymized with Zaeucoila. All species included in Zaeucoila are systematically treated, and now amounts to twelve, seven of which are described as new here: Zaeucoila bitiburculata new species, Z. fidalgoii new species, Z. infuscata new species, Z. johnsonii new species, Z. lignys new species, Z. normae new species, Z. patera new species. The following new combinations are proposed and species redescribed: Zaeucoila grenadensis (Ashmead), new combination; Z. robusta (Ashmead), new combination; Z. flavipes (Ashmead), new combination. Agrostocynips diastrophi (Ashmead), Agrostocynips clavatus D ́ıaz, and Agrostocynips enneatoma (D ́ıaz) are new synonyms of Zaeucoila robusta. Zaeucoila incompleta (Kieffer), Z. triangu- lifera Kieffer, and Z. unicarinata Ashmead are redescribed. Zaeucoila is an unusual genus of Zaeucoilini in its wide distribution area: it can be found from southern Argentina well into the eastern United States and southern Canada; no other zaeucoiline genus shows such a pattern. Host records and geographic data for Zaeucoila are brought up to date, as well as a key to species. Zeucoila are primary parasitoids of Agromyzidae, including Liriomyza trifolii and other species that are notable economic pests of agriculture. Tropideucoila fulvonotata (Kieffer) is transferred to Marthiella (new combination).

We present an updated catalog of North American Eucoilinae, bearing little resemblance to previous regional catalogs, which have been lagging behind in the recent systematic work in the group. The current catalog comprises 34 genera, arranged in six tribes. Of these genera, 9 are represented wholly by unidentified or undescribed species in the region, while the other 25 include 108 species recorded from the region. In comparison with previous catalogs, 24 genera and 41 species are added, and 34 species-level names are recombined, while 7 genera, five subgenera and 11 species are removed from the list of North American taxa. A modern, phylogenetically stable and type-based classification is implemented, as well as a tribal classification. In terms of nomenclatural acts, 25 new combinations are made (one is a reinstatement of an old combination); four new genus-levels synonymies are made (Tetramerocera Ashmead junior synonym of Ganaspis Fo ̈rster, Bewelda Quinlan and Aporeucoela Kieffer junior synonyms of Hexacola Fo ̈rster, Pentaplastidia Weld junior synonym of Trybliographa Fo ̈rster); eight new species-level synonymies are made; two species names are removed from synonymy; one new replacement name given (Hexacola pennsylvanicus for Hexacola subaperta Kieffer 1907 nec (Kieffer 1901a)).