The parasitoid wasp genusAlphomelonMason, 1981 is revised, based on a combination of basic morphology (dichotomous key and brief diagnostic descriptions), DNA barcoding, biology (host data and wasp cocoons), and distribution data. A total of 49 species is considered; the genus is almost entirely Neotropical (48 species recorded from that region), but three species reach the Nearctic, with one of them extending as far north as 45° N in Canada.Alphomelonparasitizes exclusively Hesperiinae caterpillars (Lepidoptera: Hesperiidae), mostly feeding on monocots in the families Arecaceae, Bromeliaceae, Cannaceae, Commelinaceae, Heliconiaceae, and Poaceae. Most wasp species parasitize either on one or very few (2–4) host species, usually within one or two hesperiine genera; but some species can parasitize several hosts from up to nine different hesperiine genera. Among species with available data for their cocoons, roughly half weave solitary cocoons (16) and half are gregarious (17); cocoons tend to be surrounded by a rather distinctive, coarse silk (especially in solitary species, but also distinguishable in some gregarious species). Neither morphology nor DNA barcoding alone was sufficient on its own to delimit all species properly; by integrating all available evidence (even if incomplete, as available data for every species is different) a foundation is provided for future studies incorporating more specimens, especially from South America. The following 30new speciesare described:cruzi,itatiaiensis, andpalomae, authored by Shimbori & Fernandez-Triana; andadrianguadamuzi,amazonas,andydeansi,calixtomoragai,carolinacanoae,christerhanssoni,diniamartinezae,duvalierbricenoi,eldaarayae,eliethcantillanoae,gloriasihezarae,guillermopereirai,hazelcambroneroae,josecortesi,keineraragoni,luciarosae,manuelriosi,mikesharkeyi,osvaldoespinozai,paramelanoscelis,paranigriceps,petronariosae,ricardocaleroi,rigoi,rostermoragai,sergioriosi, andyanayacu, authored by Fernandez-Triana & Shimbori.

The Aleiodes melanopterus (Erichson, 1848) species-group includes 21 species, of which seven are known from the Neotropical region: A. flavistigma Shaw, 1993, A

Four new species of the Aleiodes apicalis (Brullé) species group (Hymenoptera: Braconidae: Rogadinae) from the Neotropical Region are described and illustrated: Aleiodes ambrosiaenew species. from Peru, A. aquilesinew species from Costa Rica, and A. sachambrosiaenew species and A. tapirapenew species from Brazil. We also add new distribution records for Aleiodes molestus Cresson, from Costa Rica. With the addition of the new species, the A. apicalis species group has 11 species from the New World, six of which are recorded from Neotropical Region.

Aleiodes Wesmael is the most diverse rogadine genus worldwide, with specialized koinobiont endoparasitic development in Lepidoptera caterpillars resulting in mummification of the host remains. This paper focuses on describing new Aleiodes species from the Yanayacu Biological Station, with special interest in those with biological information. We describe 24 new species (Aleiodes albidactyl sp. n., Aleiodes albigena sp. n., Aleiodes albiviria sp. n., Aleiodes bimaculatus sp. n., Aleiodes cacuangoi sp. n., Aleiodes colberti sp.n., Aleiodes delicatus sp. n., Aleiodes dyeri sp. n., Aleiodes elleni sp. n., Aleiodes falloni sp. n., Aleiodes frosti sp.n., Aleiodes kingmani sp. n., Aleiodes longikeros sp. n., Aleiodes luteosicarius sp. n., Aleiodes marilynae sp. n., Aleiodes mirandae sp. n., Aleiodes napo sp. n., Aleiodes nubicola sp. n., Aleiodes onyx sp. n., Aleiodes shakirae sp. n., Aleiodes stewarti sp. n., Aleiodes townsendi sp. n., Aleiodes tzantza sp. n., and Aleiodes yanayacu sp.n.) from Napo Province in Ecuador, 16 of which were reared from host caterpillars. With these results 89 species of Neotropical Aleiodes are now known, with 41 of themhost records. The most commonly reared species were in the circumscriptus/gastritor species-group, and mostly associated with Geometridae hosts (six of ten species). Three species of seriatus species-group, in contrast, were each reared from a different family. One of these species (i.e. A. frosti sp. n.), reared from Notodontidae, cuts a posterior radial opening in the mummy for emergence, a unique behavior in Aleiodes, recorded here for the first time. A. luteosicarius sp. n. is the first described species from Ecuador in the pallidator species-group. Differing from previously described pallidator species, which attack only Lymantriinae larvae, A. luteosicarius sp. n. attacks several species of Arctiinae larvae, being both subfamilies within Erebidae with densely setose caterpillars. We also describe new species of the gressitti and pulchripes species-groups.