Chalcid wasps are insects within the superfamily Chalcidoidea, part of the order Hymenoptera. The superfamily contains some 22,500 known species, and an estimated total diversity of more than 500,000 species, meaning the vast majority have yet to be discovered and described. The name "chalcid" is often confused with the name "chalcidid", though the latter refers strictly to one constituent family, the Chalcididae, rather than the superfamily as a whole; accordingly, most recent publications (e.g.,) use the name "chalcidoid" when referring to members of the superfamily.
Sawflies are wasp-like insects that are in the suborder Symphyta within the order Hymenoptera, alongside ants, bees, and wasps. The common name comes from the saw-like appearance of the ovipositor, which the females use to cut into the plants where they lay their eggs. The name is associated especially with the Tenthredinoidea, by far the largest superfamily in the suborder, with about 7,000 known species; in the entire suborder, there are 8,000 described species in more than 800 genera. Symphyta is paraphyletic, consisting of several basal groups within the order Hymenoptera, each one rooted inside the previous group, ending with the Apocrita which are not sawflies.
The superfamily Ichneumonoidea contains one extinct and three extant families, including the two largest families within Hymenoptera: Ichneumonidae and Braconidae. The group is thought to contain as many as 100,000 species, many of which have not yet been described. Like other parasitoid wasps, they were long placed in the "Parasitica", variously considered as an infraorder or an unranked clade, now known to be paraphyletic.
Halictidae is the second-largest family of bees with nearly 4,500 species. They are commonly called sweat bees, as they are often attracted to perspiration. Halictid species are an extremely diverse group that can vary greatly in appearance. These bees occur all over the world and are found on every continent except Antarctica. Usually dark-colored and often metallic, halictids are found in various sizes, colors and patterns. Several species are all or partly green and a few are red, purple, or blue. A number of them have yellow markings, especially the males, which commonly have yellow faces, a pattern widespread among the various families of bees. The family is one of many with short tongues and is best distinguished by the arcuate basal vein found on the wing. Females in this family tend to be larger than the males. They are the group for which the term 'eusocial' was first coined by entomologist, Suzanne Batra.
Pelecinus polyturator is a species of wasp in the family Pelecinidae. The large glossy black insects are the most common and well-known members of the family. The adults drink nectar, and they live in crop fields, woods, and suburban gardens throughout North, Central, and South America. Their antennae are long and the females have an elongated, cylindrical, articulated metasoma. They are parasitoids that lay their eggs directly into grubs of the June beetle buried in the soil. The adults can be found in the late summer.
The Hymenopteran superfamily of parasitoid wasps, Platygastroidea, has often been treated as a lineage within the superfamily Proctotrupoidea, but most classifications since 1977 have recognized it as an independent group within the Proctotrupomorpha. It is presently has some 4000 described species. They are exclusively parasitic in nature.
The hymenopteran family Platygastridae is a moderate-sized group of exclusively parasitoid wasps, mostly very small (1–2 mm), black, and shining, with geniculate (elbowed) antennae that have an eight-segmented flagellum. The wings sometimes lack venation, though they may have slight fringes of setae.
The Pamphilioidea are a small superfamily within the Symphyta, containing some 250 living species restricted to the temperate regions of Eurasia and North America. These hymenopterans share the distinctive feature of a very large, almost prognathous head, which is widest ventrally.
The hymenopteran family Scelionidae is a very large cosmopolitan group of exclusively parasitoid wasps, mostly small (0.5–10 mm), often black, often highly sculptured, with (typically) elbowed antennae that have a 9- or 10-segmented flagellum. It was once considered to be a subfamily of the Platygastridae, but has been revived in the most recent classification of Platygastroidea.
The Stephanidae, sometimes called crown wasps, are a family of parasitoid wasps. They are the only living members of the superfamily Stephanoidea. Stephanidae has at least 345 living species in 11 genera. The family is considered cosmopolitan in distribution, with the highest species concentrations in subtropical and moderate climate zones. Stephanidae also contain four extinct genera described from both compression fossils and inclusions in amber.
The Ceraphronoidea are a small hymenopteran superfamily that includes only two families, and a total of some 800 species, though a great many species are still undescribed. It is a poorly known group as a whole, and most are believed to be parasitoid or hyperparasitoids.
The Megaspilidae are a small hymenopteran family with 13 genera in two subfamilies, and some 450 known species, with a great many species still undescribed. It is a poorly known group as a whole, though most are believed to be parasitoids, and a few hyperparasitoids. Many are found in the soil, and of these, a number are wingless.
Myrmeciites is an extinct form genus of bulldog ants in the subfamily Myrmeciinae of the family Formicidae, which contains three described species and two fossils not placed beyond the genus level. Described in 2006 from Ypresian stage deposits, all three of the described species and one unplaced fossil are from British Columbia, Canada, while the second unplaced fossil is from Washington State, USA. These ants were large, with the largest specimens collected reaching 3 centimetres (1.2 in). The behaviour of these ants would have been similar to extant Myrmeciinae ants, such as solitary foraging, nesting either in the soil or trees, and leaving no pheromone trail to food sources. Due to the poor preservation of these ants, their phylogenetic position among Myrmeciinae is unclear, and no type species has been designated. These ants are classified as incertae sedis in Myrmeciinae, but some writers have classified it as incertae sedis within the insect order Hymenoptera. This reclassification, however, has not been accepted; instead, Myrmeciites remains in Myrmeciinae.
Scelioninae is a subfamily of wasps in the family Scelionidae. It is a very large cosmopolitan group of exclusively parasitoid wasps, mostly small (0.5–10 mm), often black, often highly sculptured, usually with geniculate (elbowed) antennae that have a 9- or 10-segmented flagellum. It was formerly classified as a subfamily of the Platygastridae, but in 2021 the family Scelionidae was revived, containing the subfamilies Scelioninae, Teleasinae, and Telenominae.
Sparasion is a genus of wasps belonging to the family Sparasionidae, within the superfamily Platygastridae. The genus has specimens widespread in Eurasia, Africa, and temperate North America.
Neuroscelionidae is a family of wasps in the superfamily Platygastroidea. It contains only one extant genus, Neuroscelio, with two other genera known from fossils. Members of Neuroscelio are known from Southeast Asia and Australia. Their hosts are unknown.
Nixonia is a genus of wasps. It is the only member of the family Nixoniidae in the superfamily Platygastroidea. They are amongst the largest of the platygastroids at up to 9 mm in length. Members of the genus are known from Africa, the Indian subcontinent and Southeast Asia. The biology of only one species is known, which parasitizes orthopteran eggs.
Janzenella is a genus of wasp, the only member of the family Janzenellidae within the superfamily Platygastroidea. It contains only a single living species, Janzenella innupta, which has only been collected in Costa Rica. Fossil members of the living species have also been described from Miocene aged Dominican amber. A Late Eocene fossil species, Janzenella theia is known from specimens entombed in Baltic amber.
Geoscelionidae is a family of wasps in the superfamily Platygastroidea. It contains three extant species in two genera, native to South America and Africa, and several other genera known from fossils. It was originally erected as the tribe Geoscelionini within Scelionidae. It was raised to a full family in 2021.
Sparasionidae is a family of wasps in the superfamily Platygastroidea. Known species are parasitoids of the eggs of orthopterans.
